diff --git a/hyracks-cli/.classpath b/hyracks-cli/.classpath
index ba0bb5a..93843eb 100644
--- a/hyracks-cli/.classpath
+++ b/hyracks-cli/.classpath
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="src" output="target/classes" path="src/main/java"/>
-	<classpathentry kind="src" path="target/generated-sources/javacc"/>
+	<classpathentry kind="src" output="target/classes" path="target/generated-sources/javacc"/>
 	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.6"/>
 	<classpathentry kind="con" path="org.maven.ide.eclipse.MAVEN2_CLASSPATH_CONTAINER"/>
 	<classpathentry kind="output" path="target/classes"/>
diff --git a/hyracks-cli/.settings/org.eclipse.jdt.core.prefs b/hyracks-cli/.settings/org.eclipse.jdt.core.prefs
index f7947fa..a80ec7b 100644
--- a/hyracks-cli/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-cli/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Thu Aug 05 10:16:23 PDT 2010
+#Fri May 20 19:34:08 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-control-cc/.settings/org.eclipse.jdt.core.prefs b/hyracks-control-cc/.settings/org.eclipse.jdt.core.prefs
index 1b67f41..375e12e 100644
--- a/hyracks-control-cc/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-control-cc/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Fri Jul 30 17:52:26 PDT 2010
+#Fri May 20 19:34:07 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-control-cc/src/main/java/edu/uci/ics/hyracks/control/cc/scheduler/naive/NaiveScheduler.java b/hyracks-control-cc/src/main/java/edu/uci/ics/hyracks/control/cc/scheduler/naive/NaiveScheduler.java
index f40e8cd..c433bf9 100644
--- a/hyracks-control-cc/src/main/java/edu/uci/ics/hyracks/control/cc/scheduler/naive/NaiveScheduler.java
+++ b/hyracks-control-cc/src/main/java/edu/uci/ics/hyracks/control/cc/scheduler/naive/NaiveScheduler.java
@@ -67,7 +67,6 @@
             String[] opParts = null;
             if (!jas.allocations.containsKey(oid)) {
                 Set<ConstraintExpression> opConstraints = jas.opConstraints.get(oid);
-                System.err.println("Constraints: " + opConstraints);
                 for (ConstraintExpression ce : opConstraints) {
                     int nParts = getNumPartitions(oid, ce);
                     if (nParts != -1) {
@@ -137,12 +136,9 @@
     }
 
     private int getNumPartitions(OperatorDescriptorId oid, ConstraintExpression ce) {
-        System.err.println(ce);
         if (ce.getTag() == ExpressionTag.RELATIONAL) {
             RelationalExpression re = (RelationalExpression) ce;
             if (re.getOperator() == RelationalExpression.Operator.EQUAL) {
-                System.err.println("Left: " + re.getLeft());
-                System.err.println("Right: " + re.getRight());
                 if (re.getLeft().getTag() == ConstraintExpression.ExpressionTag.PARTITION_COUNT) {
                     return getNumPartitions(oid, (PartitionCountExpression) re.getLeft(), re.getRight());
                 } else if (re.getRight().getTag() == ConstraintExpression.ExpressionTag.PARTITION_COUNT) {
@@ -209,4 +205,4 @@
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/hyracks-control-common/.settings/org.eclipse.jdt.core.prefs b/hyracks-control-common/.settings/org.eclipse.jdt.core.prefs
index 9387c03..450f5c4 100644
--- a/hyracks-control-common/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-control-common/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Fri Jul 30 07:32:49 PDT 2010
+#Fri May 20 19:34:04 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-control-nc/.settings/org.eclipse.jdt.core.prefs b/hyracks-control-nc/.settings/org.eclipse.jdt.core.prefs
index 05fa00c..dfac000 100644
--- a/hyracks-control-nc/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-control-nc/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Tue Sep 28 12:04:33 PDT 2010
+#Fri May 20 19:34:05 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-dataflow-common/.settings/org.eclipse.jdt.core.prefs b/hyracks-dataflow-common/.settings/org.eclipse.jdt.core.prefs
index 8496bf4..450f5c4 100644
--- a/hyracks-dataflow-common/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-dataflow-common/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Thu Jul 29 14:49:35 PDT 2010
+#Fri May 20 19:34:04 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/comparators/DoubleBinaryComparatorFactory.java b/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/comparators/DoubleBinaryComparatorFactory.java
new file mode 100644
index 0000000..983dcb8
--- /dev/null
+++ b/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/comparators/DoubleBinaryComparatorFactory.java
@@ -0,0 +1,25 @@
+package edu.uci.ics.hyracks.dataflow.common.data.comparators;
+
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.DoubleSerializerDeserializer;
+
+public class DoubleBinaryComparatorFactory implements IBinaryComparatorFactory {
+    private static final long serialVersionUID = 1L;
+
+    public static final DoubleBinaryComparatorFactory INSTANCE = new DoubleBinaryComparatorFactory();
+
+    private DoubleBinaryComparatorFactory() {
+    }
+
+    @Override
+    public IBinaryComparator createBinaryComparator() {
+        return new IBinaryComparator() {
+            @Override
+            public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {   
+                return Double.compare(DoubleSerializerDeserializer.getDouble(b1, s1), DoubleSerializerDeserializer
+                        .getDouble(b2, s2));
+            }
+        };
+    }
+}
\ No newline at end of file
diff --git a/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/marshalling/DoubleSerializerDeserializer.java b/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/marshalling/DoubleSerializerDeserializer.java
new file mode 100644
index 0000000..82c80e6
--- /dev/null
+++ b/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/marshalling/DoubleSerializerDeserializer.java
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.common.data.marshalling;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+
+public class DoubleSerializerDeserializer implements ISerializerDeserializer<Double> {
+    private static final long serialVersionUID = 1L;
+
+    public static final DoubleSerializerDeserializer INSTANCE = new DoubleSerializerDeserializer();
+
+    private DoubleSerializerDeserializer() {
+    }
+
+    @Override
+    public Double deserialize(DataInput in) throws HyracksDataException {
+        try {
+            return in.readDouble();
+        } catch (IOException e) {
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void serialize(Double instance, DataOutput out) throws HyracksDataException {
+        try {
+            out.writeDouble(instance.doubleValue());
+        } catch (IOException e) {
+            throw new HyracksDataException(e);
+        }
+    }
+
+    public static double getDouble(byte[] bytes, int offset) {
+        return Double.longBitsToDouble(getLongBits(bytes, offset));
+    }
+
+    public static int getIntBits(byte[] bytes, int offset) {
+        return IntegerSerializerDeserializer.getInt(bytes, offset);
+    }
+
+    public static long getLongBits(byte[] bytes, int offset) {
+        return Integer64SerializerDeserializer.getLong(bytes, offset);
+    }
+    
+    
+}
\ No newline at end of file
diff --git a/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/marshalling/Integer64SerializerDeserializer.java b/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/marshalling/Integer64SerializerDeserializer.java
new file mode 100644
index 0000000..effc092
--- /dev/null
+++ b/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/marshalling/Integer64SerializerDeserializer.java
@@ -0,0 +1,44 @@
+package edu.uci.ics.hyracks.dataflow.common.data.marshalling;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+
+public class Integer64SerializerDeserializer implements ISerializerDeserializer<Long> {
+
+    private static final long serialVersionUID = 1L;
+
+    public static final Integer64SerializerDeserializer INSTANCE = new Integer64SerializerDeserializer();
+
+    private Integer64SerializerDeserializer() {
+    }
+
+    @Override
+    public Long deserialize(DataInput in) throws HyracksDataException {
+        try {
+            return in.readLong();
+        } catch (IOException e) {
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void serialize(Long instance, DataOutput out) throws HyracksDataException {
+        try {
+            out.writeLong(instance.longValue());
+        } catch (IOException ioe) {
+            throw new HyracksDataException(ioe);
+        }
+    }
+
+    public static long getLong(byte[] bytes, int offset) {
+        return (((long) (bytes[offset] & 0xff)) << 56) + (((long) (bytes[offset + 1] & 0xff)) << 48)
+                + (((long) (bytes[offset + 2] & 0xff)) << 40) + (((long) (bytes[offset + 3] & 0xff)) << 32)
+                + (((long) (bytes[offset + 4] & 0xff)) << 24) + (((long) (bytes[offset + 5] & 0xff)) << 16)
+                + (((long) (bytes[offset + 6] & 0xff)) << 8) + (((long) (bytes[offset + 7] & 0xff)) << 0);
+    }
+
+}
diff --git a/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/util/StringUtils.java b/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/util/StringUtils.java
index dbe6386..d11245b 100644
--- a/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/util/StringUtils.java
+++ b/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/data/util/StringUtils.java
@@ -14,56 +14,199 @@
  */
 package edu.uci.ics.hyracks.dataflow.common.data.util;
 
+import java.io.DataOutput;
+import java.io.IOException;
+
 public class StringUtils {
-    public static int charSize(byte[] b, int s) {
-        int c = (int) b[s] & 0xff;
-        switch (c >> 4) {
-            case 0:
-            case 1:
-            case 2:
-            case 3:
-            case 4:
-            case 5:
-            case 6:
-            case 7:
-                return 1;
+	public static char charAt(byte[] b, int s) {
+		int c = b[s] & 0xff;
+		switch (c >> 4) {
+		case 0:
+		case 1:
+		case 2:
+		case 3:
+		case 4:
+		case 5:
+		case 6:
+		case 7:
+			return (char) c;
 
-            case 12:
-            case 13:
-                return 2;
+		case 12:
+		case 13:
+			return (char) (((c & 0x1F) << 6) | ((b[s + 1]) & 0x3F));
 
-            case 14:
-                return 3;
-        }
-        throw new IllegalStateException();
-    }
+		case 14:
+			return (char) (((c & 0x0F) << 12) | (((b[s + 1]) & 0x3F) << 6) | (((b[s + 2]) & 0x3F) << 0));
 
-    public static char charAt(byte[] b, int s) {
-        int c = (int) b[s] & 0xff;
-        switch (c >> 4) {
-            case 0:
-            case 1:
-            case 2:
-            case 3:
-            case 4:
-            case 5:
-            case 6:
-            case 7:
-                return (char) c;
+		default:
+			throw new IllegalArgumentException();
+		}
+	}
 
-            case 12:
-            case 13:
-                return (char) (((c & 0x1F) << 6) | (((int) b[s + 1]) & 0x3F));
+	public static int charSize(byte[] b, int s) {
+		int c = b[s] & 0xff;
+		switch (c >> 4) {
+		case 0:
+		case 1:
+		case 2:
+		case 3:
+		case 4:
+		case 5:
+		case 6:
+		case 7:
+			return 1;
 
-            case 14:
-                return (char) (((c & 0x0F) << 12) | ((((int) b[s + 1]) & 0x3F) << 6) | ((((int) b[s + 2]) & 0x3F) << 0));
+		case 12:
+		case 13:
+			return 2;
 
-            default:
-                throw new IllegalArgumentException();
-        }
-    }
+		case 14:
+			return 3;
+		}
+		throw new IllegalStateException();
+	}
 
-    public static int getUTFLen(byte[] b, int s) {
-        return ((b[s] & 0xff) << 8) + ((b[s + 1] & 0xff) << 0);
-    }
+	public static int getModifiedUTF8Len(char c) {
+		if (c >= 0x0000 && c <= 0x007F) {
+			return 1;
+		} else if (c <= 0x07FF) {
+			return 2;
+		} else {
+			return 3;
+		}
+	}
+
+	public static int getStrLen(byte[] b, int s) {
+		int pos = s + 2;
+		int end = pos + getUTFLen(b, s);
+		int charCount = 0;
+		while (pos < end) {
+			charCount++;
+			pos += charSize(b, pos);
+		}
+		return charCount;
+	}
+
+	public static int getUTFLen(byte[] b, int s) {
+		return ((b[s] & 0xff) << 8) + ((b[s + 1] & 0xff) << 0);
+	}
+
+	public static char toLowerCase(char c) {
+		switch (c) {
+		case 'A':
+			return 'a';
+		case 'B':
+			return 'b';
+		case 'C':
+			return 'c';
+		case 'D':
+			return 'd';
+		case 'E':
+			return 'e';
+		case 'F':
+			return 'f';
+		case 'G':
+			return 'g';
+		case 'H':
+			return 'h';
+		case 'I':
+			return 'i';
+		case 'J':
+			return 'j';
+		case 'K':
+			return 'k';
+		case 'L':
+			return 'l';
+		case 'M':
+			return 'm';
+		case 'N':
+			return 'n';
+		case 'O':
+			return 'o';
+		case 'P':
+			return 'p';
+		case 'Q':
+			return 'q';
+		case 'R':
+			return 'r';
+		case 'S':
+			return 's';
+		case 'T':
+			return 't';
+		case 'U':
+			return 'u';
+		case 'V':
+			return 'v';
+		case 'W':
+			return 'w';
+		case 'X':
+			return 'x';
+		case 'Y':
+			return 'y';
+		case 'Z':
+			return 'z';
+		case 'Ä':
+			return 'ä';
+		case 'Ǟ':
+			return 'ǟ';
+		case 'Ë':
+			return 'ë';
+		case 'Ḧ':
+			return 'ḧ';
+		case 'Ï':
+			return 'ï';
+		case 'Ḯ':
+			return 'ḯ';
+		case 'Ö':
+			return 'ö';
+		case 'Ȫ':
+			return 'ȫ';
+		case 'Ṏ':
+			return 'ṏ';
+		case 'Ü':
+			return 'ü';
+		case 'Ǖ':
+			return 'ǖ';
+		case 'Ǘ':
+			return 'ǘ';
+		case 'Ǚ':
+			return 'ǚ';
+		case 'Ǜ':
+			return 'ǜ';
+		case 'Ṳ':
+			return 'ṳ';
+		case 'Ṻ':
+			return 'ṻ';
+		case 'Ẅ':
+			return 'ẅ';
+		case 'Ẍ':
+			return 'ẍ';
+		case 'Ÿ':
+			return 'ÿ';
+		default:
+			// since I probably missed some chars above
+			// use Java to convert to lower case to be safe
+			return Character.toLowerCase(c);
+		}
+	}
+
+	public static void writeCharAsModifiedUTF8(char c, DataOutput dos)
+			throws IOException {
+
+		if (c >= 0x0000 && c <= 0x007F) {
+			dos.writeByte(c);
+		} else if (c <= 0x07FF) {
+			dos.writeByte((byte) (0xC0 | ((c >> 6) & 0x3F)));
+			dos.writeByte((byte) (0x80 | (c & 0x3F)));
+		} else {
+			dos.writeByte((byte) (0xE0 | ((c >> 12) & 0x0F)));
+			dos.writeByte((byte) (0x80 | ((c >> 6) & 0x3F)));
+			dos.writeByte((byte) (0x80 | (c & 0x3F)));
+		}
+	}
+
+	public static void writeUTF8Len(int len, DataOutput dos) throws IOException {
+		dos.write((len >>> 8) & 0xFF);
+		dos.write((len >>> 0) & 0xFF);
+	}
 }
\ No newline at end of file
diff --git a/hyracks-dataflow-std/.settings/org.eclipse.jdt.core.prefs b/hyracks-dataflow-std/.settings/org.eclipse.jdt.core.prefs
index 1ca1bd4..450f5c4 100644
--- a/hyracks-dataflow-std/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-dataflow-std/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Thu Jul 29 14:32:56 PDT 2010
+#Fri May 20 19:34:04 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/AvgAggregatorDescriptorFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/AvgAggregatorDescriptorFactory.java
new file mode 100644
index 0000000..c4d623c
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/AvgAggregatorDescriptorFactory.java
@@ -0,0 +1,136 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.aggregators;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+
+public class AvgAggregatorDescriptorFactory implements IAggregatorDescriptorFactory {
+    private static final long serialVersionUID = 1L;
+    private final int avgField;
+    private int outField = -1;
+
+    public AvgAggregatorDescriptorFactory(int avgField) {
+        this.avgField = avgField;
+    }
+
+    public AvgAggregatorDescriptorFactory(int avgField, int outField) {
+        this.avgField = avgField;
+        this.outField = outField;
+    }
+
+    @Override
+    public IAggregatorDescriptor createAggregator(IHyracksStageletContext ctx, RecordDescriptor inRecordDescriptor,
+            RecordDescriptor outRecordDescriptor, int[] keyFields) throws HyracksDataException {
+
+        if (this.outField < 0)
+            this.outField = keyFields.length;
+
+        return new IAggregatorDescriptor() {
+
+            @Override
+            public void reset() {
+
+            }
+
+            @Override
+            public void outputResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, outField);
+                int sum = IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(),
+                        tupleOffset + accessor.getFieldSlotsLength() + fieldStart);
+                int count = IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(),
+                        tupleOffset + accessor.getFieldSlotsLength() + fieldStart + 4);
+
+                try {
+                    tupleBuilder.getDataOutput().writeInt(sum / count);
+                    tupleBuilder.addFieldEndOffset();
+                } catch (IOException e) {
+                    throw new HyracksDataException();
+                }
+            }
+
+            @Override
+            public void outputPartialResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, outField);
+                int sum = IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(),
+                        tupleOffset + accessor.getFieldSlotsLength() + fieldStart);
+                int count = IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(),
+                        tupleOffset + accessor.getFieldSlotsLength() + fieldStart + 4);
+                try {
+                    tupleBuilder.getDataOutput().writeInt(sum);
+                    tupleBuilder.getDataOutput().writeInt(count);
+                    tupleBuilder.addFieldEndOffset();
+                } catch (IOException e) {
+                    throw new HyracksDataException();
+                }
+            }
+
+            @Override
+            public void init(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                // Init aggregation value
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, avgField);
+                int sum = IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(),
+                        tupleOffset + accessor.getFieldSlotsLength() + fieldStart);
+                int count = 1;
+
+                try {
+                    tupleBuilder.getDataOutput().writeInt(sum);
+                    tupleBuilder.getDataOutput().writeInt(count);
+                    tupleBuilder.addFieldEndOffset();
+                } catch (IOException e) {
+                    throw new HyracksDataException();
+                }
+            }
+
+            @Override
+            public void close() {
+
+            }
+
+            @Override
+            public int aggregate(IFrameTupleAccessor accessor, int tIndex, byte[] data, int offset, int length)
+                    throws HyracksDataException {
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, outField);
+                int sum1 = IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(),
+                        tupleOffset + accessor.getFieldSlotsLength() + fieldStart);
+                int count1 = 1;
+
+                int sum2 = IntegerSerializerDeserializer.getInt(data, offset);
+                int count2 = IntegerSerializerDeserializer.getInt(data, offset + 4);
+
+                ByteBuffer buf = ByteBuffer.wrap(data, offset, 8);
+                buf.putInt(sum1 + sum2);
+                buf.putInt(count1 + count2);
+
+                return 8;
+            }
+        };
+    }
+
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/ConcatAggregatorDescriptorFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/ConcatAggregatorDescriptorFactory.java
new file mode 100644
index 0000000..90edf4a
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/ConcatAggregatorDescriptorFactory.java
@@ -0,0 +1,190 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.aggregators;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+
+public class ConcatAggregatorDescriptorFactory implements IAggregatorDescriptorFactory {
+    private static final long serialVersionUID = 1L;
+    private static final int INIT_ACCUMULATORS_SIZE = 8;
+    private final int concatField;
+    private int outField = -1;
+
+    /**
+     * Initialize the aggregator, with the field to be concatenated.
+     * 
+     * @param concatField
+     */
+    public ConcatAggregatorDescriptorFactory(int concatField) {
+        this.concatField = concatField;
+    }
+
+    /**
+     * Initialize the aggregator, with the field index to be concatenated, and
+     * also the field where the aggregation result will be outputted.
+     * 
+     * @param concatField
+     * @param outField
+     */
+    public ConcatAggregatorDescriptorFactory(int concatField, int outField) {
+        this.concatField = concatField;
+        this.outField = outField;
+    }
+
+    /**
+     * Create a concatenation aggregator. A byte buffer will be allocated inside of the
+     * aggregator to contain the partial aggregation results. A reference will be written
+     * onto the output frame for indexing the aggregation result from the buffer.
+     */
+    @Override
+    public IAggregatorDescriptor createAggregator(IHyracksStageletContext ctx, RecordDescriptor inRecordDescriptor,
+            RecordDescriptor outRecordDescriptor, final int[] keyFields) throws HyracksDataException {
+
+        if (this.outField < 0)
+            this.outField = keyFields.length;
+
+        return new IAggregatorDescriptor() {
+
+            byte[][] buf = new byte[INIT_ACCUMULATORS_SIZE][];
+
+            int currentAggregatorIndex = -1;
+            int aggregatorCount = 0;
+
+            @Override
+            public void init(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                // Initialize the aggregation value
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, concatField);
+                int fieldLength = accessor.getFieldLength(tIndex, concatField);
+                int appendOffset = tupleOffset + accessor.getFieldSlotsLength() + fieldStart;
+                // Get the initial value
+                currentAggregatorIndex++;
+                if (currentAggregatorIndex >= buf.length) {
+                    byte[][] newBuf = new byte[buf.length * 2][];
+                    for (int i = 0; i < buf.length; i++) {
+                        newBuf[i] = buf[i];
+                    }
+                    this.buf = newBuf;
+                }
+                buf[currentAggregatorIndex] = new byte[fieldLength];
+                System.arraycopy(accessor.getBuffer().array(), appendOffset, buf[currentAggregatorIndex], 0,
+                        fieldLength);
+                // Update the aggregator index
+                aggregatorCount++;
+
+                try {
+                    tupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, currentAggregatorIndex);
+                } catch (IOException e) {
+                    throw new HyracksDataException();
+                }
+            }
+
+            @Override
+            public void reset() {
+                currentAggregatorIndex = -1;
+                aggregatorCount = 0;
+            }
+
+            @Override
+            public void close() {
+                currentAggregatorIndex = -1;
+                aggregatorCount = 0;
+                for (int i = 0; i < buf.length; i++) {
+                    buf[i] = null;
+                }
+            }
+
+            @Override
+            public int aggregate(IFrameTupleAccessor accessor, int tIndex, byte[] data, int offset, int length)
+                    throws HyracksDataException {
+                int refIndex = IntegerSerializerDeserializer.getInt(data, offset);
+                // FIXME Should be done in binary way
+                StringBuilder sbder = new StringBuilder();
+                sbder.append(UTF8StringSerializerDeserializer.INSTANCE.deserialize(new DataInputStream(
+                        new ByteArrayInputStream(buf[refIndex]))));
+                // Get the new data
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, concatField);
+                int fieldLength = accessor.getFieldLength(tIndex, concatField);
+                sbder.append(UTF8StringSerializerDeserializer.INSTANCE.deserialize(new DataInputStream(
+                        new ByteArrayInputStream(accessor.getBuffer().array(), tupleOffset
+                                + accessor.getFieldSlotsLength() + fieldStart, fieldLength))));
+
+                ByteArrayOutputStream baos = new ByteArrayOutputStream();
+                UTF8StringSerializerDeserializer.INSTANCE.serialize(sbder.toString(), new DataOutputStream(baos));
+                buf[refIndex] = baos.toByteArray();
+                return 4;
+            }
+
+            @Override
+            public void outputResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, outField);
+                int refIndex = IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(), tupleOffset
+                        + accessor.getFieldSlotsLength() + fieldStart);
+
+                try {
+                    if (refIndex >= 0)
+                        tupleBuilder.getDataOutput().write(buf[refIndex]);
+                    else {
+                        int fieldLength = accessor.getFieldLength(tIndex, outField);
+                        tupleBuilder.getDataOutput().write(accessor.getBuffer().array(),
+                                tupleOffset + accessor.getFieldSlotsLength() + fieldStart + 4, fieldLength - 4);
+                    }
+                    tupleBuilder.addFieldEndOffset();
+                } catch (IOException e) {
+                    throw new HyracksDataException();
+                }
+            }
+
+            @Override
+            public void outputPartialResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldOffset = accessor.getFieldStartOffset(tIndex, outField);
+                int fieldLength = accessor.getFieldLength(tIndex, outField);
+                int refIndex = IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(), tupleOffset
+                        + accessor.getFieldSlotsLength() + fieldOffset);
+
+                try {
+                    tupleBuilder.getDataOutput().writeInt(-1);
+                    if (refIndex < 0) {
+                        tupleBuilder.getDataOutput().write(accessor.getBuffer().array(),
+                                tupleOffset + accessor.getFieldSlotsLength() + fieldOffset + 4, fieldLength - 4);
+                    } else {
+                        tupleBuilder.getDataOutput().write(buf[refIndex], 0, buf[refIndex].length);
+                    }
+                    tupleBuilder.addFieldEndOffset();
+                } catch (IOException e) {
+                    throw new HyracksDataException();
+                }
+            }
+        };
+    }
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/CountAggregatorDescriptorFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/CountAggregatorDescriptorFactory.java
new file mode 100644
index 0000000..c5f0a42
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/CountAggregatorDescriptorFactory.java
@@ -0,0 +1,103 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.aggregators;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+
+public class CountAggregatorDescriptorFactory implements IAggregatorDescriptorFactory {
+    private static final long serialVersionUID = 1L;
+    private int outField = -1;
+
+    public CountAggregatorDescriptorFactory() {
+    }
+
+    public CountAggregatorDescriptorFactory(int outField) {
+        this.outField = outField;
+    }
+
+    @Override
+    public IAggregatorDescriptor createAggregator(IHyracksStageletContext ctx, RecordDescriptor inRecordDescriptor,
+            RecordDescriptor outRecordDescriptor, final int[] keyFields) throws HyracksDataException {
+
+        if (this.outField < 0) {
+            this.outField = keyFields.length;
+        }
+        return new IAggregatorDescriptor() {
+
+            @Override
+            public void init(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                tupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, 1);
+            }
+
+            @Override
+            public void close() {
+            }
+
+            @Override
+            public int aggregate(IFrameTupleAccessor accessor, int tIndex, byte[] data, int offset, int length)
+                    throws HyracksDataException {
+                ByteBuffer buf = ByteBuffer.wrap(data);
+                int count = buf.getInt(offset);
+                buf.putInt(offset, count + 1);
+                return 4;
+            }
+
+            @Override
+            public void outputPartialResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, outField);
+
+                try {
+                    tupleBuilder.getDataOutput().write(accessor.getBuffer().array(),
+                            tupleOffset + accessor.getFieldSlotsLength() + fieldStart, 4);
+                    tupleBuilder.addFieldEndOffset();
+                } catch (IOException e) {
+                    throw new HyracksDataException("Failed to write int sum as a partial result.");
+                }
+            }
+
+            @Override
+            public void outputResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, outField);
+
+                try {
+                    tupleBuilder.getDataOutput().write(accessor.getBuffer().array(),
+                            tupleOffset + accessor.getFieldSlotsLength() + fieldStart, 4);
+                    tupleBuilder.addFieldEndOffset();
+                } catch (IOException e) {
+                    throw new HyracksDataException("Failed to write int sum as a partial result.");
+                }
+            }
+
+            @Override
+            public void reset() {
+
+            }
+        };
+    }
+
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/IAggregatorDescriptor.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/IAggregatorDescriptor.java
new file mode 100644
index 0000000..dfc31cd
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/IAggregatorDescriptor.java
@@ -0,0 +1,89 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.aggregators;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+
+public interface IAggregatorDescriptor {
+
+    /**
+     * Initialize the aggregator with an input tuple specified by the input
+     * frame and tuple index. This function will write the initialized partial
+     * result into the tuple builder.
+     * 
+     * @param accessor
+     * @param tIndex
+     * @param tupleBuilder
+     * @throws HyracksDataException
+     */
+    public void init(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+            throws HyracksDataException;
+
+    /**
+     * Aggregate the input tuple with the partial result specified by the bytes.
+     * The new value then is written back to the bytes field specified.
+     * It is the developer's responsibility to have the new result not exceed
+     * the given bytes.
+     * 
+     * @param accessor
+     * @param tIndex
+     * @param data
+     * @param offset
+     * @param length
+     * @return
+     * @throws HyracksDataException
+     */
+    public int aggregate(IFrameTupleAccessor accessor, int tIndex, byte[] data, int offset, int length)
+            throws HyracksDataException;
+
+    /**
+     * Output the partial aggregation result to an array tuple builder.
+     * Necessary additional information for aggregation should be maintained.
+     * For example, for an aggregator calculating AVG, the count and also the
+     * current average should be maintained as the partial results.
+     * 
+     * @param accessor
+     * @param tIndex
+     * @param tupleBuilder
+     * @throws HyracksDataException
+     */
+    public void outputPartialResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+            throws HyracksDataException;
+
+    /**
+     * Output the final aggregation result to an array tuple builder.
+     * 
+     * @param accessor
+     * @param tIndex
+     * @param tupleBuilder
+     * @return
+     * @throws HyracksDataException
+     */
+    public void outputResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+            throws HyracksDataException;
+
+    /**
+     * reset the internal states
+     */
+    public void reset();
+
+    /**
+     * Close the aggregator. Necessary clean-up code should be implemented here.
+     */
+    public void close();
+
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/IAggregatorDescriptorFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/IAggregatorDescriptorFactory.java
new file mode 100644
index 0000000..e324e1c
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/IAggregatorDescriptorFactory.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.aggregators;
+
+import java.io.Serializable;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+
+public interface IAggregatorDescriptorFactory extends Serializable {
+
+    /**
+     * Create an aggregator.
+     * 
+     * @param ctx
+     * @param inRecordDescriptor
+     * @param outRecordDescriptor
+     * @param keyFields
+     * @return
+     * @throws HyracksDataException
+     */
+    IAggregatorDescriptor createAggregator(IHyracksStageletContext ctx, RecordDescriptor inRecordDescriptor,
+            RecordDescriptor outRecordDescriptor, int[] keyFields) throws HyracksDataException;
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/IntSumAggregatorDescriptorFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/IntSumAggregatorDescriptorFactory.java
new file mode 100644
index 0000000..e07b123
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/IntSumAggregatorDescriptorFactory.java
@@ -0,0 +1,118 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.aggregators;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+
+public class IntSumAggregatorDescriptorFactory implements IAggregatorDescriptorFactory {
+    private static final long serialVersionUID = 1L;
+    private final int aggField;
+    private int outField = -1;
+
+    public IntSumAggregatorDescriptorFactory(int aggField) {
+        this.aggField = aggField;
+    }
+
+    public IntSumAggregatorDescriptorFactory(int aggField, int outField) {
+        this.aggField = aggField;
+        this.outField = outField;
+    }
+
+    @Override
+    public IAggregatorDescriptor createAggregator(IHyracksStageletContext ctx, RecordDescriptor inRecordDescriptor,
+            RecordDescriptor outRecordDescriptor, final int[] keyFields) throws HyracksDataException {
+
+        if (this.outField < 0) {
+            this.outField = keyFields.length;
+        }
+
+        return new IAggregatorDescriptor() {
+
+            @Override
+            public void init(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                int sum = 0;
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, aggField);
+                sum += IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(),
+                        tupleOffset + accessor.getFieldSlotsLength() + fieldStart);
+
+                tupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, sum);
+            }
+
+            @Override
+            public void close() {
+            }
+
+            @Override
+            public int aggregate(IFrameTupleAccessor accessor, int tIndex, byte[] data, int offset, int length)
+                    throws HyracksDataException {
+                int sum = 0;
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, aggField);
+                sum += IntegerSerializerDeserializer.getInt(accessor.getBuffer().array(),
+                        tupleOffset + accessor.getFieldSlotsLength() + fieldStart);
+                // Update the value of tuple 2
+                ByteBuffer buf = ByteBuffer.wrap(data);
+                sum += buf.getInt(offset);
+                buf.putInt(offset, sum);
+                return 4;
+            }
+
+            @Override
+            public void outputPartialResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, outField);
+
+                try {
+                    tupleBuilder.getDataOutput().write(accessor.getBuffer().array(),
+                            tupleOffset + accessor.getFieldSlotsLength() + fieldStart, 4);
+                    tupleBuilder.addFieldEndOffset();
+                } catch (IOException e) {
+                    throw new HyracksDataException("Failed to write int sum as a partial result.");
+                }
+            }
+
+            @Override
+            public void outputResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                int tupleOffset = accessor.getTupleStartOffset(tIndex);
+                int fieldStart = accessor.getFieldStartOffset(tIndex, outField);
+
+                try {
+                    tupleBuilder.getDataOutput().write(accessor.getBuffer().array(),
+                            tupleOffset + accessor.getFieldSlotsLength() + fieldStart, 4);
+                    tupleBuilder.addFieldEndOffset();
+                } catch (IOException e) {
+                    throw new HyracksDataException("Failed to write int sum as a partial result.");
+                }
+            }
+
+            @Override
+            public void reset() {
+                
+            }
+        };
+    }
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/MultiAggregatorDescriptorFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/MultiAggregatorDescriptorFactory.java
new file mode 100644
index 0000000..58d0da7
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/MultiAggregatorDescriptorFactory.java
@@ -0,0 +1,94 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.aggregators;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+
+public class MultiAggregatorDescriptorFactory implements IAggregatorDescriptorFactory {
+    private static final long serialVersionUID = 1L;
+    private final IAggregatorDescriptorFactory[] aggregatorFactories;
+
+    public MultiAggregatorDescriptorFactory(IAggregatorDescriptorFactory[] aggregatorFactories) {
+        this.aggregatorFactories = aggregatorFactories;
+    }
+
+    @Override
+    public IAggregatorDescriptor createAggregator(final IHyracksStageletContext ctx,
+            final RecordDescriptor inRecordDescriptor, final RecordDescriptor outRecordDescriptor, final int[] keyFields)
+            throws HyracksDataException {
+
+        final IAggregatorDescriptor[] aggregators = new IAggregatorDescriptor[this.aggregatorFactories.length];
+        for (int i = 0; i < aggregators.length; i++) {
+            aggregators[i] = aggregatorFactories[i].createAggregator(ctx, inRecordDescriptor, outRecordDescriptor,
+                    keyFields);
+        }
+
+        return new IAggregatorDescriptor() {
+
+            @Override
+            public void init(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                for (int i = 0; i < aggregators.length; i++) {
+                    aggregators[i].init(accessor, tIndex, tupleBuilder);
+                }
+            }
+
+            @Override
+            public int aggregate(IFrameTupleAccessor accessor, int tIndex, byte[] data, int offset, int length)
+                    throws HyracksDataException {
+                int adjust = 0;
+                for (int i = 0; i < aggregators.length; i++) {
+                    adjust += aggregators[i].aggregate(accessor, tIndex, data, offset + adjust, length - adjust);
+                }
+                return adjust;
+            }
+
+            @Override
+            public void outputPartialResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                for (int i = 0; i < aggregators.length; i++) {
+                    aggregators[i].outputPartialResult(accessor, tIndex, tupleBuilder);
+                }
+            }
+
+            @Override
+            public void outputResult(IFrameTupleAccessor accessor, int tIndex, ArrayTupleBuilder tupleBuilder)
+                    throws HyracksDataException {
+                for (int i = 0; i < aggregators.length; i++) {
+                    aggregators[i].outputResult(accessor, tIndex, tupleBuilder);
+                }
+            }
+
+            @Override
+            public void close() {
+                for (int i = 0; i < aggregators.length; i++) {
+                    aggregators[i].close();
+                }
+            }
+
+            @Override
+            public void reset() {
+                for (int i = 0; i < aggregators.length; i++) {
+                    aggregators[i].reset();
+                }
+            }
+
+        };
+    }
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/MultiAggregatorFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/MultiAggregatorFactory.java
index 957c453..eb9c12d 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/MultiAggregatorFactory.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/aggregators/MultiAggregatorFactory.java
@@ -24,7 +24,6 @@
 import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
 import edu.uci.ics.hyracks.dataflow.std.group.IAccumulatingAggregator;
 import edu.uci.ics.hyracks.dataflow.std.group.IAccumulatingAggregatorFactory;
-import edu.uci.ics.hyracks.dataflow.std.group.ISpillableAccumulatingAggregator;
 
 public class MultiAggregatorFactory implements IAccumulatingAggregatorFactory {
     private static final long serialVersionUID = 1L;
@@ -36,92 +35,6 @@
     }
 
     @Override
-    public ISpillableAccumulatingAggregator createSpillableAggregator(IHyracksStageletContext ctx,
-            RecordDescriptor inRecordDesc, final RecordDescriptor outRecordDescriptor) {
-        final ISpillableFieldValueResultingAggregator aggregators[] = new ISpillableFieldValueResultingAggregator[aFactories.length];
-        for (int i = 0; i < aFactories.length; ++i) {
-            aggregators[i] = aFactories[i].createSpillableFieldValueResultingAggregator();
-        }
-        final ArrayTupleBuilder tb = new ArrayTupleBuilder(outRecordDescriptor.getFields().length);
-        return new ISpillableAccumulatingAggregator() {
-            private boolean pending;
-
-            @Override
-            public boolean output(FrameTupleAppender appender, IFrameTupleAccessor accessor, int tIndex,
-                    int[] keyFieldIndexes) throws HyracksDataException {
-                if (!pending) {
-                    tb.reset();
-                    for (int i = 0; i < keyFieldIndexes.length; ++i) {
-                        tb.addField(accessor, tIndex, keyFieldIndexes[i]);
-                    }
-                    DataOutput dos = tb.getDataOutput();
-                    for (int i = 0; i < aggregators.length; ++i) {
-                        aggregators[i].output(dos);
-                        tb.addFieldEndOffset();
-                    }
-                }
-                if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
-                    pending = true;
-                    return false;
-                }
-                return true;
-            }
-
-            @Override
-            public void init(IFrameTupleAccessor accessor, int tIndex) throws HyracksDataException {
-                tb.reset();
-                for (int i = 0; i < aggregators.length; ++i) {
-                    aggregators[i].init(accessor, tIndex);
-                }
-                pending = false;
-            }
-
-            @Override
-            public void accumulate(IFrameTupleAccessor accessor, int tIndex) throws HyracksDataException {
-                for (int i = 0; i < aggregators.length; ++i) {
-                    aggregators[i].accumulate(accessor, tIndex);
-                }
-            }
-
-            @Override
-            public void initFromPartial(IFrameTupleAccessor accessor, int tIndex, int[] keyFieldIndexes)
-                    throws HyracksDataException {
-                tb.reset();
-                for (int i = 0; i < aggregators.length; i++) {
-                    aggregators[i].initFromPartial(accessor, tIndex, keyFieldIndexes.length + i);
-                }
-                pending = false;
-            }
-
-            @Override
-            public void accumulatePartialResult(IFrameTupleAccessor accessor, int tIndex, int[] keyFieldIndexes)
-                    throws HyracksDataException {
-                for (int i = 0; i < aggregators.length; i++) {
-                    aggregators[i].accumulatePartialResult(accessor, tIndex, keyFieldIndexes.length + i);
-                }
-
-            }
-
-            @Override
-            public boolean output(FrameTupleAppender appender, ArrayTupleBuilder tbder) throws HyracksDataException {
-                if (!pending) {
-                    // TODO Here to be fixed:
-                    DataOutput dos = tbder.getDataOutput();
-                    for (int i = 0; i < aggregators.length; ++i) {
-                        aggregators[i].output(dos);
-                        tbder.addFieldEndOffset();
-                    }
-                }
-                if (!appender.append(tbder.getFieldEndOffsets(), tbder.getByteArray(), 0, tbder.getSize())) {
-                    pending = true;
-                    return false;
-                }
-                return true;
-            }
-        };
-    }
-
-    @Override
     public IAccumulatingAggregator createAggregator(IHyracksStageletContext ctx, RecordDescriptor inRecordDesc,
             RecordDescriptor outRecordDescriptor) throws HyracksDataException {
         final IFieldValueResultingAggregator aggregators[] = new IFieldValueResultingAggregator[aFactories.length];
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/IRecordReader.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/IRecordReader.java
index 4516c8d..5d94c12 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/IRecordReader.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/IRecordReader.java
@@ -16,8 +16,8 @@
 
 public interface IRecordReader {
 
-	  public boolean read(Object[] record) throws Exception;
+    public boolean read(Object[] record) throws Exception;
 
-      public void close();
-      
+    public void close();
+
 }
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/IRecordWriter.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/IRecordWriter.java
index a319727..679088f 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/IRecordWriter.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/IRecordWriter.java
@@ -17,10 +17,9 @@
 import java.io.File;
 
 public interface IRecordWriter {
-	  
-      public void close();
-      
-      public void write(Object[] record) throws Exception;
 
-	
+    public void close();
+
+    public void write(Object[] record) throws Exception;
+
 }
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/PlainFileWriterOperatorDescriptor.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/PlainFileWriterOperatorDescriptor.java
index 530207d..d599fee 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/PlainFileWriterOperatorDescriptor.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/PlainFileWriterOperatorDescriptor.java
@@ -63,7 +63,7 @@
     @Override
     public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
             IRecordDescriptorProvider recordDescProvider, final int partition, int nPartitions)
-    throws HyracksDataException {
+            throws HyracksDataException {
         // Output files
         final FileSplit[] splits = fileSplitProvider.getFileSplits();
         // Frame accessor
@@ -95,7 +95,7 @@
                     frameTupleAccessor.reset(buffer);
                     for (int tIndex = 0; tIndex < frameTupleAccessor.getTupleCount(); tIndex++) {
                         int start = frameTupleAccessor.getTupleStartOffset(tIndex)
-                        + frameTupleAccessor.getFieldSlotsLength();
+                                + frameTupleAccessor.getFieldSlotsLength();
                         bbis.setByteBuffer(buffer, start);
                         Object[] record = new Object[recordDescriptor.getFields().length];
                         for (int i = 0; i < record.length; ++i) {
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/RecordFileScanOperatorDescriptor.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/RecordFileScanOperatorDescriptor.java
index aa6635d..38ac1a3 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/RecordFileScanOperatorDescriptor.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/RecordFileScanOperatorDescriptor.java
@@ -66,14 +66,14 @@
     protected IRecordReader createRecordReader(File file, RecordDescriptor desc) throws Exception {
         return new RecordReaderImpl(file, desc);
     }
-    
+
     @Override
-	protected void configure() throws Exception {
-		// currently a no-op, but is meant to initialize , if required before it is asked 
-		// to create a record reader
-		// this is executed at the node and is useful for operators that could not be 
-		// initialized from the client completely, because of lack of information specific 
-		// to the node where the operator gets executed. 
-		
-	}
+    protected void configure() throws Exception {
+        // currently a no-op, but is meant to initialize , if required before it is asked 
+        // to create a record reader
+        // this is executed at the node and is useful for operators that could not be 
+        // initialized from the client completely, because of lack of information specific 
+        // to the node where the operator gets executed. 
+
+    }
 }
\ No newline at end of file
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/RecordWriter.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/RecordWriter.java
index 1c52b25..1858a73 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/RecordWriter.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/file/RecordWriter.java
@@ -14,73 +14,72 @@
  */
 package edu.uci.ics.hyracks.dataflow.std.file;
 
-import java.io.BufferedReader;
 import java.io.BufferedWriter;
 import java.io.IOException;
-import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 
-public abstract class RecordWriter implements IRecordWriter{
+import edu.uci.ics.hyracks.dataflow.std.util.StringSerializationUtils;
 
-	 
-	protected final BufferedWriter bufferedWriter;
+public abstract class RecordWriter implements IRecordWriter {
+
+    protected final BufferedWriter bufferedWriter;
     protected final int[] columns;
     protected final char separator;
-    
-    public static final char COMMA = ',';
-    
-    public RecordWriter(Object [] args) throws Exception{
-    	OutputStream outputStream = createOutputStream(args);
-    	if(outputStream != null){
-    		bufferedWriter = new BufferedWriter(new OutputStreamWriter(createOutputStream(args)));
-    	}else{
-    		bufferedWriter = null;
-    	}
-    	this.columns = null;
-    	this.separator = COMMA;
-    }
-    
-    public RecordWriter(int []columns, char separator, Object[] args) throws Exception{
-    	OutputStream outputStream = createOutputStream(args);
-    	if(outputStream != null){
-    		bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream));
-    	}else{
-    		bufferedWriter = null;
-    	}
-    	this.columns = columns;
-    	this.separator = separator;
-    }
-    
-	@Override
-     public void close() {
-         try {
-             bufferedWriter.close();
-         } catch (IOException e) {
-             e.printStackTrace();
-         }
-     }
 
-     @Override
-     public void write(Object[] record) throws Exception {
-         if (columns == null) {
-             for (int i = 0; i < record.length; ++i) {
-                 if (i != 0) {
-                     bufferedWriter.write(separator);
-                 }
-                 bufferedWriter.write(String.valueOf(record[i]));
-             }
-         } else {
-             for (int i = 0; i < columns.length; ++i) {
-                 if (i != 0) {
-                     bufferedWriter.write(separator);
-                 }
-                 bufferedWriter.write(String.valueOf(record[columns[i]]));
-             }
-         }
-         bufferedWriter.write("\n");
-     }
-     
-     public abstract OutputStream createOutputStream(Object[] args) throws Exception;
-   
+    public static final char COMMA = ',';
+
+    public RecordWriter(Object[] args) throws Exception {
+        OutputStream outputStream = createOutputStream(args);
+        if (outputStream != null) {
+            bufferedWriter = new BufferedWriter(new OutputStreamWriter(createOutputStream(args)));
+        } else {
+            bufferedWriter = null;
+        }
+        this.columns = null;
+        this.separator = COMMA;
+    }
+
+    public RecordWriter(int[] columns, char separator, Object[] args) throws Exception {
+        OutputStream outputStream = createOutputStream(args);
+        if (outputStream != null) {
+            bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream));
+        } else {
+            bufferedWriter = null;
+        }
+        this.columns = columns;
+        this.separator = separator;
+    }
+
+    @Override
+    public void close() {
+        try {
+            bufferedWriter.close();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    @Override
+    public void write(Object[] record) throws Exception {
+        if (columns == null) {
+            for (int i = 0; i < record.length; ++i) {
+                if (i != 0) {
+                    bufferedWriter.write(separator);
+                }
+                bufferedWriter.write(StringSerializationUtils.toString(record[i]));
+            }
+        } else {
+            for (int i = 0; i < columns.length; ++i) {
+                if (i != 0) {
+                    bufferedWriter.write(separator);
+                }
+                bufferedWriter.write(StringSerializationUtils.toString(record[columns[i]]));
+            }
+        }
+        bufferedWriter.write("\n");
+    }
+
+    public abstract OutputStream createOutputStream(Object[] args) throws Exception;
+
 }
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/DeserializedPreclusteredGroupOperator.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/DeserializedPreclusteredGroupOperator.java
index 4b7aff3..fc5f282 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/DeserializedPreclusteredGroupOperator.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/DeserializedPreclusteredGroupOperator.java
@@ -23,98 +23,97 @@
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.std.base.IOpenableDataWriterOperator;
 
-public class DeserializedPreclusteredGroupOperator implements
-		IOpenableDataWriterOperator {
-	private final int[] groupFields;
+public class DeserializedPreclusteredGroupOperator implements IOpenableDataWriterOperator {
+    private final int[] groupFields;
 
-	private final IComparator[] comparators;
+    private final IComparator[] comparators;
 
-	private final IGroupAggregator aggregator;
+    private final IGroupAggregator aggregator;
 
-	private Object[] lastData;
+    private Object[] lastData;
 
-	private IOpenableDataWriter<Object[]> writer;
+    private IOpenableDataWriter<Object[]> writer;
 
-	private List<Object[]> buffer;
+    private List<Object[]> buffer;
 
-	private IOpenableDataReader<Object[]> reader;
+    private IOpenableDataReader<Object[]> reader;
 
-	public DeserializedPreclusteredGroupOperator(int[] groupFields,
-			IComparator[] comparators, IGroupAggregator aggregator) {
-		this.groupFields = groupFields;
-		this.comparators = comparators;
-		this.aggregator = aggregator;
-		buffer = new ArrayList<Object[]>();
-		reader = new IOpenableDataReader<Object[]>() {
-			private int idx;
+    public DeserializedPreclusteredGroupOperator(int[] groupFields, IComparator[] comparators,
+            IGroupAggregator aggregator) {
+        this.groupFields = groupFields;
+        this.comparators = comparators;
+        this.aggregator = aggregator;
+        buffer = new ArrayList<Object[]>();
+        reader = new IOpenableDataReader<Object[]>() {
+            private int idx;
 
-			@Override
-			public void open() {
-				idx = 0;
-			}
+            @Override
+            public void open() {
+                idx = 0;
+            }
 
-			@Override
-			public void close() {
-			}
+            @Override
+            public void close() {
+            }
 
-			@Override
-			public Object[] readData() {
-				return idx >= buffer.size() ? null : buffer.get(idx++);
-			}
-		};
-	}
+            @Override
+            public Object[] readData() {
+                return idx >= buffer.size() ? null : buffer.get(idx++);
+            }
+        };
+    }
 
-	@Override
-	public void close() throws HyracksDataException {
-		if (!buffer.isEmpty()) {
-			aggregate();
-		}
-		writer.close();
-		try {
-			aggregator.close();
-		} catch (Exception e) {
-			throw new HyracksDataException(e);
-		}
-	}
+    @Override
+    public void close() throws HyracksDataException {
+        if (!buffer.isEmpty()) {
+            aggregate();
+        }
+        writer.close();
+        try {
+            aggregator.close();
+        } catch (Exception e) {
+            throw new HyracksDataException(e);
+        }
+    }
 
-	private void aggregate() throws HyracksDataException {
-		reader.open();
-		aggregator.aggregate(reader, writer);
-		reader.close();
-		buffer.clear();
-	}
+    private void aggregate() throws HyracksDataException {
+        reader.open();
+        aggregator.aggregate(reader, writer);
+        reader.close();
+        buffer.clear();
+    }
 
-	@Override
-	public void open() throws HyracksDataException {
-		lastData = null;
-		writer.open();
-	}
+    @Override
+    public void open() throws HyracksDataException {
+        lastData = null;
+        writer.open();
+    }
 
-	@Override
-	public void setDataWriter(int index, IOpenableDataWriter<Object[]> writer) {
-		if (index != 0) {
-			throw new IllegalArgumentException();
-		}
-		this.writer = writer;
-	}
+    @Override
+    public void setDataWriter(int index, IOpenableDataWriter<Object[]> writer) {
+        if (index != 0) {
+            throw new IllegalArgumentException();
+        }
+        this.writer = writer;
+    }
 
-	@Override
-	public void writeData(Object[] data) throws HyracksDataException {
-		if (lastData != null && compare(data, lastData) != 0) {
-			aggregate();
-		}
-		lastData = data;
-		buffer.add(data);
-	}
+    @Override
+    public void writeData(Object[] data) throws HyracksDataException {
+        if (lastData != null && compare(data, lastData) != 0) {
+            aggregate();
+        }
+        lastData = data;
+        buffer.add(data);
+    }
 
-	private int compare(Object[] d1, Object[] d2) {
-		for (int i = 0; i < groupFields.length; ++i) {
-			int fIdx = groupFields[i];
-			int c = comparators[i].compare(d1[fIdx], d2[fIdx]);
-			if (c != 0) {
-				return c;
-			}
-		}
-		return 0;
-	}
+    private int compare(Object[] d1, Object[] d2) {
+        for (int i = 0; i < groupFields.length; ++i) {
+            int fIdx = groupFields[i];
+            int c = comparators[i].compare(d1[fIdx], d2[fIdx]);
+            if (c != 0) {
+                return c;
+            }
+        }
+        return 0;
+    }
 }
\ No newline at end of file
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ExternalGroupOperatorDescriptor.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ExternalGroupOperatorDescriptor.java
new file mode 100644
index 0000000..65f7f08
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ExternalGroupOperatorDescriptor.java
@@ -0,0 +1,620 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.group;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.LinkedList;
+import java.util.List;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.comm.IFrameWriter;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.IActivityGraphBuilder;
+import edu.uci.ics.hyracks.api.dataflow.IOperatorDescriptor;
+import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
+import edu.uci.ics.hyracks.api.job.JobSpecification;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
+import edu.uci.ics.hyracks.dataflow.common.io.RunFileReader;
+import edu.uci.ics.hyracks.dataflow.common.io.RunFileWriter;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.IAggregatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.IAggregatorDescriptorFactory;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractActivityNode;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputSinkOperatorNodePushable;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryOutputSourceOperatorNodePushable;
+import edu.uci.ics.hyracks.dataflow.std.util.ReferenceEntry;
+import edu.uci.ics.hyracks.dataflow.std.util.ReferencedPriorityQueue;
+
+public class ExternalGroupOperatorDescriptor extends AbstractOperatorDescriptor {
+    private static final long serialVersionUID = 1L;
+    /**
+     * The input frame identifier (in the job environment)
+     */
+    private static final String GROUPTABLES = "gtables";
+    /**
+     * The runs files identifier (in the job environment)
+     */
+    private static final String RUNS = "runs";
+    private final int[] keyFields;
+    private final IBinaryComparatorFactory[] comparatorFactories;
+    private final INormalizedKeyComputerFactory firstNormalizerFactory;
+    private final IAggregatorDescriptorFactory aggregatorFactory;
+    private final IAggregatorDescriptorFactory mergeFactory;
+    private final int framesLimit;
+    private final ISpillableTableFactory spillableTableFactory;
+    private final boolean isOutputSorted;
+
+    public ExternalGroupOperatorDescriptor(JobSpecification spec, int[] keyFields, int framesLimit,
+            IBinaryComparatorFactory[] comparatorFactories, INormalizedKeyComputerFactory firstNormalizerFactory,
+            IAggregatorDescriptorFactory aggregatorFactory, IAggregatorDescriptorFactory mergeFactory,
+            RecordDescriptor recordDescriptor, ISpillableTableFactory spillableTableFactory, boolean isOutputSorted) {
+        super(spec, 1, 1);
+        this.framesLimit = framesLimit;
+        if (framesLimit <= 1) {
+            /**
+             * Minimum of 2 frames: 1 for input records, and 1 for output
+             * aggregation results.
+             */
+            throw new IllegalStateException("frame limit should at least be 2, but it is " + framesLimit + "!");
+        }
+
+        this.aggregatorFactory = aggregatorFactory;
+        this.mergeFactory = mergeFactory;
+        this.keyFields = keyFields;
+        this.comparatorFactories = comparatorFactories;
+        this.firstNormalizerFactory = firstNormalizerFactory;
+        this.spillableTableFactory = spillableTableFactory;
+        this.isOutputSorted = isOutputSorted;
+
+        /**
+         * Set the record descriptor. Note that since
+         * this operator is a unary operator,
+         * only the first record descriptor is used here.
+         */
+        recordDescriptors[0] = recordDescriptor;
+    }
+
+    @Override
+    public void contributeTaskGraph(IActivityGraphBuilder builder) {
+        AggregateActivity aggregateAct = new AggregateActivity();
+        MergeActivity mergeAct = new MergeActivity();
+
+        builder.addTask(aggregateAct);
+        builder.addSourceEdge(0, aggregateAct, 0);
+
+        builder.addTask(mergeAct);
+        builder.addTargetEdge(0, mergeAct, 0);
+
+        builder.addBlockingEdge(aggregateAct, mergeAct);
+    }
+
+    private class AggregateActivity extends AbstractActivityNode {
+
+        private static final long serialVersionUID = 1L;
+
+        @Override
+        public IOperatorDescriptor getOwner() {
+            return ExternalGroupOperatorDescriptor.this;
+        }
+
+        @Override
+        public IOperatorNodePushable createPushRuntime(final IHyracksStageletContext ctx,
+                final IOperatorEnvironment env, IRecordDescriptorProvider recordDescProvider, int partition,
+                int nPartitions) throws HyracksDataException {
+            final ISpillableTable gTable = spillableTableFactory.buildSpillableTable(ctx, keyFields,
+                    comparatorFactories, firstNormalizerFactory, aggregatorFactory,
+                    recordDescProvider.getInputRecordDescriptor(getOperatorId(), 0), recordDescriptors[0],
+                    ExternalGroupOperatorDescriptor.this.framesLimit);
+            final FrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(),
+                    recordDescProvider.getInputRecordDescriptor(getOperatorId(), 0));
+            IOperatorNodePushable op = new AbstractUnaryInputSinkOperatorNodePushable() {
+
+                /**
+                 * Run files
+                 */
+                private LinkedList<RunFileReader> runs;
+
+                @Override
+                public void open() throws HyracksDataException {
+                    runs = new LinkedList<RunFileReader>();
+                    gTable.reset();
+                }
+
+                @Override
+                public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
+                    accessor.reset(buffer);
+                    int tupleCount = accessor.getTupleCount();
+                    for (int i = 0; i < tupleCount; i++) {
+                        /**
+                         * If the group table is too large, flush the table into
+                         * a run file.
+                         */
+                        if (!gTable.insert(accessor, i)) {
+                            flushFramesToRun();
+                            if (!gTable.insert(accessor, i))
+                                throw new HyracksDataException(
+                                        "Failed to insert a new buffer into the aggregate operator!");
+                        }
+                    }
+                }
+
+                @Override
+                public void flush() throws HyracksDataException {
+
+                }
+
+                @Override
+                public void close() throws HyracksDataException {
+                    if (gTable.getFrameCount() >= 0) {
+                        if (runs.size() <= 0) {
+                            /**
+                             * All in memory
+                             */
+                            env.set(GROUPTABLES, gTable);
+                        } else {
+                            /**
+                             * flush the memory into the run file.
+                             */
+                            flushFramesToRun();
+                            gTable.close();
+                        }
+                    }
+                    env.set(RUNS, runs);
+                }
+
+                private void flushFramesToRun() throws HyracksDataException {
+                    FileReference runFile;
+                    try {
+                        runFile = ctx.getJobletContext().createWorkspaceFile(
+                                ExternalGroupOperatorDescriptor.class.getSimpleName());
+                    } catch (IOException e) {
+                        throw new HyracksDataException(e);
+                    }
+                    RunFileWriter writer = new RunFileWriter(runFile, ctx.getIOManager());
+                    writer.open();
+                    try {
+                        gTable.sortFrames();
+                        gTable.flushFrames(writer, true);
+                    } catch (Exception ex) {
+                        throw new HyracksDataException(ex);
+                    } finally {
+                        writer.close();
+                    }
+                    gTable.reset();
+                    runs.add(((RunFileWriter) writer).createReader());
+                }
+            };
+            return op;
+        }
+    }
+
+    private class MergeActivity extends AbstractActivityNode {
+
+        private static final long serialVersionUID = 1L;
+
+        @Override
+        public IOperatorDescriptor getOwner() {
+            return ExternalGroupOperatorDescriptor.this;
+        }
+
+        @Override
+        public IOperatorNodePushable createPushRuntime(final IHyracksStageletContext ctx,
+                final IOperatorEnvironment env, IRecordDescriptorProvider recordDescProvider, int partition,
+                int nPartitions) throws HyracksDataException {
+            final IBinaryComparator[] comparators = new IBinaryComparator[comparatorFactories.length];
+            for (int i = 0; i < comparatorFactories.length; ++i) {
+                comparators[i] = comparatorFactories[i].createBinaryComparator();
+            }
+            final IAggregatorDescriptor currentWorkingAggregator = mergeFactory.createAggregator(ctx,
+                    recordDescriptors[0], recordDescriptors[0], keyFields);
+            final int[] storedKeys = new int[keyFields.length];
+            /**
+             * Get the list of the fields in the stored records.
+             */
+            for (int i = 0; i < keyFields.length; ++i) {
+                storedKeys[i] = i;
+            }
+            /**
+             * Tuple builder
+             */
+            final ArrayTupleBuilder tupleBuilder = new ArrayTupleBuilder(recordDescriptors[0].getFields().length);
+
+            IOperatorNodePushable op = new AbstractUnaryOutputSourceOperatorNodePushable() {
+                /**
+                 * Input frames, one for each run file.
+                 */
+                private List<ByteBuffer> inFrames;
+
+                /**
+                 * Output frame.
+                 */
+                private ByteBuffer outFrame, writerFrame;
+
+                /**
+                 * List of the run files to be merged
+                 */
+                private LinkedList<RunFileReader> runs;
+
+                /**
+                 * how many frames to be read ahead once
+                 */
+                private int runFrameLimit = 1;
+
+                private int[] currentFrameIndexInRun;
+                private int[] currentRunFrames;
+                private final FrameTupleAppender outFrameAppender = new FrameTupleAppender(ctx.getFrameSize());
+                private final FrameTupleAccessor outFrameAccessor = new FrameTupleAccessor(ctx.getFrameSize(),
+                        recordDescriptors[0]);
+                private ArrayTupleBuilder finalTupleBuilder;
+                private FrameTupleAppender writerFrameAppender;
+
+                @SuppressWarnings("unchecked")
+                public void initialize() throws HyracksDataException {
+                    runs = (LinkedList<RunFileReader>) env.get(RUNS);
+                    writer.open();
+                    try {
+                        if (runs.size() <= 0) {
+                            ISpillableTable gTable = (ISpillableTable) env.get(GROUPTABLES);
+                            if (gTable != null) {
+                                if (isOutputSorted)
+                                    gTable.sortFrames();
+                                gTable.flushFrames(writer, false);
+                            }
+                            env.set(GROUPTABLES, null);
+                        } else {
+                            long start = System.currentTimeMillis();
+                            inFrames = new ArrayList<ByteBuffer>();
+                            outFrame = ctx.allocateFrame();
+                            outFrameAppender.reset(outFrame, true);
+                            outFrameAccessor.reset(outFrame);
+                            while (runs.size() > 0) {
+                                try {
+                                    doPass(runs);
+                                } catch (Exception e) {
+                                    throw new HyracksDataException(e);
+                                }
+                            }
+                            inFrames.clear();
+                            long end = System.currentTimeMillis();
+                            System.out.println("merge time " + (end - start));
+                        }
+                    } finally {
+                        writer.close();
+                    }
+                    env.set(RUNS, null);
+                }
+
+                private void doPass(LinkedList<RunFileReader> runs) throws HyracksDataException {
+                    FileReference newRun = null;
+                    IFrameWriter writer = this.writer;
+                    boolean finalPass = false;
+
+                    while (inFrames.size() + 2 < framesLimit) {
+                        inFrames.add(ctx.allocateFrame());
+                    }
+                    int runNumber;
+                    if (runs.size() + 2 <= framesLimit) {
+                        finalPass = true;
+                        runFrameLimit = (framesLimit - 2) / runs.size();
+                        runNumber = runs.size();
+                    } else {
+                        runNumber = framesLimit - 2;
+                        newRun = ctx.getJobletContext().createWorkspaceFile(
+                                ExternalGroupOperatorDescriptor.class.getSimpleName());
+                        writer = new RunFileWriter(newRun, ctx.getIOManager());
+                        writer.open();
+                    }
+                    try {
+                        currentFrameIndexInRun = new int[runNumber];
+                        currentRunFrames = new int[runNumber];
+                        /**
+                         * Create file readers for each input run file, only
+                         * for the ones fit into the inFrames
+                         */
+                        RunFileReader[] runFileReaders = new RunFileReader[runNumber];
+                        FrameTupleAccessor[] tupleAccessors = new FrameTupleAccessor[inFrames.size()];
+                        Comparator<ReferenceEntry> comparator = createEntryComparator(comparators);
+                        ReferencedPriorityQueue topTuples = new ReferencedPriorityQueue(ctx.getFrameSize(),
+                                recordDescriptors[0], runNumber, comparator);
+                        /**
+                         * current tuple index in each run
+                         */
+                        int[] tupleIndices = new int[runNumber];
+
+                        for (int runIndex = runNumber - 1; runIndex >= 0; runIndex--) {
+                            tupleIndices[runIndex] = 0;
+                            // Load the run file
+                            runFileReaders[runIndex] = runs.get(runIndex);
+                            runFileReaders[runIndex].open();
+
+                            currentRunFrames[runIndex] = 0;
+                            currentFrameIndexInRun[runIndex] = runIndex * runFrameLimit;
+                            for (int j = 0; j < runFrameLimit; j++) {
+                                int frameIndex = currentFrameIndexInRun[runIndex] + j;
+                                if (runFileReaders[runIndex].nextFrame(inFrames.get(frameIndex))) {
+                                    tupleAccessors[frameIndex] = new FrameTupleAccessor(ctx.getFrameSize(),
+                                            recordDescriptors[0]);
+                                    tupleAccessors[frameIndex].reset(inFrames.get(frameIndex));
+                                    currentRunFrames[runIndex]++;
+                                    if (j == 0)
+                                        setNextTopTuple(runIndex, tupleIndices, runFileReaders, tupleAccessors,
+                                                topTuples);
+                                } else {
+                                    break;
+                                }
+                            }
+                        }
+
+                        /**
+                         * Start merging
+                         */
+                        while (!topTuples.areRunsExhausted()) {
+                            /**
+                             * Get the top record
+                             */
+                            ReferenceEntry top = topTuples.peek();
+                            int tupleIndex = top.getTupleIndex();
+                            int runIndex = topTuples.peek().getRunid();
+                            FrameTupleAccessor fta = top.getAccessor();
+
+                            int currentTupleInOutFrame = outFrameAccessor.getTupleCount() - 1;
+                            if (currentTupleInOutFrame < 0
+                                    || compareFrameTuples(fta, tupleIndex, outFrameAccessor, currentTupleInOutFrame) != 0) {
+                                /**
+                                 * Initialize the first output record
+                                 * Reset the tuple builder
+                                 */
+                                tupleBuilder.reset();
+                                for (int i = 0; i < keyFields.length; i++) {
+                                    tupleBuilder.addField(fta, tupleIndex, i);
+                                }
+
+                                currentWorkingAggregator.init(fta, tupleIndex, tupleBuilder);
+                                if (!outFrameAppender.append(tupleBuilder.getFieldEndOffsets(),
+                                        tupleBuilder.getByteArray(), 0, tupleBuilder.getSize())) {
+                                    flushOutFrame(writer, finalPass);
+                                    if (!outFrameAppender.append(tupleBuilder.getFieldEndOffsets(),
+                                            tupleBuilder.getByteArray(), 0, tupleBuilder.getSize()))
+                                        throw new HyracksDataException(
+                                                "Failed to append an aggregation result to the output frame.");
+                                }
+                            } else {
+                                /**
+                                 * if new tuple is in the same group of the
+                                 * current aggregator
+                                 * do merge and output to the outFrame
+                                 */
+                                int tupleOffset = outFrameAccessor.getTupleStartOffset(currentTupleInOutFrame);
+                                int fieldOffset = outFrameAccessor.getFieldStartOffset(currentTupleInOutFrame,
+                                        keyFields.length);
+                                int fieldLength = outFrameAccessor.getFieldLength(currentTupleInOutFrame,
+                                        keyFields.length);
+                                currentWorkingAggregator.aggregate(fta, tupleIndex, outFrameAccessor.getBuffer()
+                                        .array(), tupleOffset + outFrameAccessor.getFieldSlotsLength() + fieldOffset,
+                                        fieldLength);
+                            }
+                            tupleIndices[runIndex]++;
+                            setNextTopTuple(runIndex, tupleIndices, runFileReaders, tupleAccessors, topTuples);
+                        }
+
+                        if (outFrameAppender.getTupleCount() > 0) {
+                            flushOutFrame(writer, finalPass);
+                        }
+
+                        currentWorkingAggregator.close();
+                        runs.subList(0, runNumber).clear();
+                        /**
+                         * insert the new run file into the beginning of the run
+                         * file list
+                         */
+                        if (!finalPass) {
+                            runs.add(0, ((RunFileWriter) writer).createReader());
+                        }
+                    } finally {
+                        if (!finalPass) {
+                            writer.close();
+                        }
+                    }
+                }
+
+                private void flushOutFrame(IFrameWriter writer, boolean isFinal) throws HyracksDataException {
+                    if (finalTupleBuilder == null) {
+                        finalTupleBuilder = new ArrayTupleBuilder(recordDescriptors[0].getFields().length);
+                    }
+                    if (writerFrame == null) {
+                        writerFrame = ctx.allocateFrame();
+                    }
+                    if (writerFrameAppender == null) {
+                        writerFrameAppender = new FrameTupleAppender(ctx.getFrameSize());
+                        writerFrameAppender.reset(writerFrame, true);
+                    }
+                    outFrameAccessor.reset(outFrame);
+                    for (int i = 0; i < outFrameAccessor.getTupleCount(); i++) {
+                        finalTupleBuilder.reset();
+                        for (int j = 0; j < keyFields.length; j++) {
+                            finalTupleBuilder.addField(outFrameAccessor, i, j);
+                        }
+                        if (isFinal)
+                            currentWorkingAggregator.outputResult(outFrameAccessor, i, finalTupleBuilder);
+                        else
+                            currentWorkingAggregator.outputPartialResult(outFrameAccessor, i, finalTupleBuilder);
+
+                        if (!writerFrameAppender.append(finalTupleBuilder.getFieldEndOffsets(),
+                                finalTupleBuilder.getByteArray(), 0, finalTupleBuilder.getSize())) {
+                            FrameUtils.flushFrame(writerFrame, writer);
+                            writerFrameAppender.reset(writerFrame, true);
+                            if (!writerFrameAppender.append(finalTupleBuilder.getFieldEndOffsets(),
+                                    finalTupleBuilder.getByteArray(), 0, finalTupleBuilder.getSize()))
+                                throw new HyracksDataException(
+                                        "Failed to write final aggregation result to a writer frame!");
+                        }
+                    }
+                    if (writerFrameAppender.getTupleCount() > 0) {
+                        FrameUtils.flushFrame(writerFrame, writer);
+                        writerFrameAppender.reset(writerFrame, true);
+                    }
+                    outFrameAppender.reset(outFrame, true);
+                }
+
+                private void setNextTopTuple(int runIndex, int[] tupleIndices, RunFileReader[] runCursors,
+                        FrameTupleAccessor[] tupleAccessors, ReferencedPriorityQueue topTuples)
+                        throws HyracksDataException {
+                    int runStart = runIndex * runFrameLimit;
+                    boolean existNext = false;
+                    if (tupleAccessors[currentFrameIndexInRun[runIndex]] == null || runCursors[runIndex] == null) {
+                        /**
+                         * run already closed
+                         */
+                        existNext = false;
+                    } else if (currentFrameIndexInRun[runIndex] - runStart < currentRunFrames[runIndex] - 1) {
+                        /**
+                         * not the last frame for this run
+                         */
+                        existNext = true;
+                        if (tupleIndices[runIndex] >= tupleAccessors[currentFrameIndexInRun[runIndex]].getTupleCount()) {
+                            tupleIndices[runIndex] = 0;
+                            currentFrameIndexInRun[runIndex]++;
+                        }
+                    } else if (tupleIndices[runIndex] < tupleAccessors[currentFrameIndexInRun[runIndex]]
+                            .getTupleCount()) {
+                        /**
+                         * the last frame has expired
+                         */
+                        existNext = true;
+                    } else {
+                        /**
+                         * If all tuples in the targeting frame have been
+                         * checked.
+                         */
+                        int frameOffset = runIndex * runFrameLimit;
+                        tupleIndices[runIndex] = 0;
+                        currentFrameIndexInRun[runIndex] = frameOffset;
+                        /**
+                         * read in batch
+                         */
+                        currentRunFrames[runIndex] = 0;
+                        for (int j = 0; j < runFrameLimit; j++, frameOffset++) {
+                            ByteBuffer buffer = tupleAccessors[frameOffset].getBuffer();
+                            if (runCursors[runIndex].nextFrame(buffer)) {
+                                tupleAccessors[frameOffset].reset(buffer);
+                                if (tupleAccessors[frameOffset].getTupleCount() > 0) {
+                                    existNext = true;
+                                } else {
+                                    throw new IllegalStateException("illegal: empty run file");
+                                }
+                                currentRunFrames[runIndex]++;
+                            } else {
+                                break;
+                            }
+                        }
+                    }
+
+                    if (existNext) {
+                        topTuples.popAndReplace(tupleAccessors[currentFrameIndexInRun[runIndex]],
+                                tupleIndices[runIndex]);
+                    } else {
+                        topTuples.pop();
+                        closeRun(runIndex, runCursors, tupleAccessors);
+                    }
+                }
+
+                /**
+                 * Close the run file, and also the corresponding readers and
+                 * input frame.
+                 * 
+                 * @param index
+                 * @param runCursors
+                 * @param tupleAccessor
+                 * @throws HyracksDataException
+                 */
+                private void closeRun(int index, RunFileReader[] runCursors, IFrameTupleAccessor[] tupleAccessor)
+                        throws HyracksDataException {
+                    if (runCursors[index] != null) {
+                        runCursors[index].close();
+                        runCursors[index] = null;
+                    }
+                }
+
+                private int compareFrameTuples(IFrameTupleAccessor fta1, int j1, IFrameTupleAccessor fta2, int j2) {
+                    byte[] b1 = fta1.getBuffer().array();
+                    byte[] b2 = fta2.getBuffer().array();
+                    for (int f = 0; f < keyFields.length; ++f) {
+                        int fIdx = f;
+                        int s1 = fta1.getTupleStartOffset(j1) + fta1.getFieldSlotsLength()
+                                + fta1.getFieldStartOffset(j1, fIdx);
+                        int l1 = fta1.getFieldLength(j1, fIdx);
+                        int s2 = fta2.getTupleStartOffset(j2) + fta2.getFieldSlotsLength()
+                                + fta2.getFieldStartOffset(j2, fIdx);
+                        int l2_start = fta2.getFieldStartOffset(j2, fIdx);
+                        int l2_end = fta2.getFieldEndOffset(j2, fIdx);
+                        int l2 = l2_end - l2_start;
+                        int c = comparators[f].compare(b1, s1, l1, b2, s2, l2);
+                        if (c != 0) {
+                            return c;
+                        }
+                    }
+                    return 0;
+                }
+            };
+            return op;
+        }
+
+        private Comparator<ReferenceEntry> createEntryComparator(final IBinaryComparator[] comparators) {
+            return new Comparator<ReferenceEntry>() {
+
+                @Override
+                public int compare(ReferenceEntry o1, ReferenceEntry o2) {
+                    FrameTupleAccessor fta1 = (FrameTupleAccessor) o1.getAccessor();
+                    FrameTupleAccessor fta2 = (FrameTupleAccessor) o2.getAccessor();
+                    int j1 = o1.getTupleIndex();
+                    int j2 = o2.getTupleIndex();
+                    byte[] b1 = fta1.getBuffer().array();
+                    byte[] b2 = fta2.getBuffer().array();
+                    for (int f = 0; f < keyFields.length; ++f) {
+                        int fIdx = f;
+                        int s1 = fta1.getTupleStartOffset(j1) + fta1.getFieldSlotsLength()
+                                + fta1.getFieldStartOffset(j1, fIdx);
+                        int l1 = fta1.getFieldEndOffset(j1, fIdx) - fta1.getFieldStartOffset(j1, fIdx);
+                        int s2 = fta2.getTupleStartOffset(j2) + fta2.getFieldSlotsLength()
+                                + fta2.getFieldStartOffset(j2, fIdx);
+                        int l2 = fta2.getFieldEndOffset(j2, fIdx) - fta2.getFieldStartOffset(j2, fIdx);
+                        int c = comparators[f].compare(b1, s1, l1, b2, s2, l2);
+                        if (c != 0) {
+                            return c;
+                        }
+                    }
+                    return 0;
+                }
+
+            };
+        }
+
+    }
+
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ExternalHashGroupOperatorDescriptor.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ExternalHashGroupOperatorDescriptor.java
deleted file mode 100644
index b13b087..0000000
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ExternalHashGroupOperatorDescriptor.java
+++ /dev/null
@@ -1,692 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package edu.uci.ics.hyracks.dataflow.std.group;
-
-import java.io.IOException;
-import java.nio.ByteBuffer;
-import java.util.ArrayList;
-import java.util.Comparator;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.logging.Logger;
-
-import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
-import edu.uci.ics.hyracks.api.comm.IFrameWriter;
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.IActivityGraphBuilder;
-import edu.uci.ics.hyracks.api.dataflow.IOperatorDescriptor;
-import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
-import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
-import edu.uci.ics.hyracks.api.dataflow.value.ITuplePartitionComputerFactory;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.api.io.FileReference;
-import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
-import edu.uci.ics.hyracks.api.job.JobSpecification;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
-import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
-import edu.uci.ics.hyracks.dataflow.common.io.RunFileReader;
-import edu.uci.ics.hyracks.dataflow.common.io.RunFileWriter;
-import edu.uci.ics.hyracks.dataflow.std.base.AbstractActivityNode;
-import edu.uci.ics.hyracks.dataflow.std.base.AbstractOperatorDescriptor;
-import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputSinkOperatorNodePushable;
-import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryOutputSourceOperatorNodePushable;
-import edu.uci.ics.hyracks.dataflow.std.util.ReferenceEntry;
-import edu.uci.ics.hyracks.dataflow.std.util.ReferencedPriorityQueue;
-
-/**
- * This is an implementation of the external hash group operator.
- * The motivation of this operator is that when tuples are processed in
- * parallel, distinguished aggregating keys partitioned on one node may exceed
- * the main memory, so aggregation results should be output onto the disk to
- * make space for aggregating more input tuples.
- */
-public class ExternalHashGroupOperatorDescriptor extends AbstractOperatorDescriptor {
-
-    /**
-     * The input frame identifier (in the job environment)
-     */
-    private static final String GROUPTABLES = "gtables";
-
-    /**
-     * The runs files identifier (in the job environment)
-     */
-    private static final String RUNS = "runs";
-
-    /**
-     * The fields used for grouping (grouping keys).
-     */
-    private final int[] keyFields;
-
-    /**
-     * The comparator for checking the grouping conditions, corresponding to the {@link #keyFields}.
-     */
-    private final IBinaryComparatorFactory[] comparatorFactories;
-
-    /**
-     * The aggregator factory for the aggregating field, corresponding to the {@link #aggregateFields}.
-     */
-    private IAccumulatingAggregatorFactory aggregatorFactory;
-
-    /**
-     * The maximum number of frames in the main memory.
-     */
-    private final int framesLimit;
-
-    /**
-     * Indicate whether the final output will be sorted or not.
-     */
-    private final boolean sortOutput;
-
-    /**
-     * Partition computer factory
-     */
-    private final ITuplePartitionComputerFactory tpcf;
-
-    /**
-     * The size of the in-memory table, which should be specified now by the
-     * creator of this operator descriptor.
-     */
-    private final int tableSize;
-
-    /**
-     * XXX Logger for debug information
-     */
-    private static Logger LOGGER = Logger.getLogger(ExternalHashGroupOperatorDescriptor.class.getName());
-
-    /**
-     * Constructor of the external hash group operator descriptor.
-     * 
-     * @param spec
-     * @param keyFields
-     *            The fields as keys of grouping.
-     * @param framesLimit
-     *            The maximum number of frames to be used in memory.
-     * @param sortOutput
-     *            Whether the output should be sorted or not. Note that if the
-     *            input data is large enough for external grouping, the output
-     *            will be sorted surely. The only case that when the output is
-     *            not sorted is when the size of the input data can be grouped
-     *            in memory and this parameter is false.
-     * @param tpcf
-     *            The partitioner.
-     * @param comparatorFactories
-     *            The comparators.
-     * @param aggregatorFactory
-     *            The aggregators.
-     * @param recordDescriptor
-     *            The record descriptor for the input data.
-     * @param tableSize
-     *            The maximum size of the in memory table usable to this
-     *            operator.
-     */
-    public ExternalHashGroupOperatorDescriptor(JobSpecification spec, int[] keyFields, int framesLimit,
-            boolean sortOutput, ITuplePartitionComputerFactory tpcf, IBinaryComparatorFactory[] comparatorFactories,
-            IAccumulatingAggregatorFactory aggregatorFactory, RecordDescriptor recordDescriptor, int tableSize) {
-        super(spec, 1, 1);
-        this.framesLimit = framesLimit;
-        if (framesLimit <= 1) {
-            // Minimum of 2 frames: 1 for input records, and 1 for output
-            // aggregation results.
-            throw new IllegalStateException();
-        }
-        this.aggregatorFactory = aggregatorFactory;
-        this.keyFields = keyFields;
-        this.comparatorFactories = comparatorFactories;
-
-        this.sortOutput = sortOutput;
-
-        this.tpcf = tpcf;
-
-        this.tableSize = tableSize;
-
-        // Set the record descriptor. Note that since this operator is a unary
-        // operator,
-        // only the first record descritpor is used here.
-        recordDescriptors[0] = recordDescriptor;
-    }
-
-    /**
-     * 
-     */
-    private static final long serialVersionUID = 1L;
-
-    /*
-     * (non-Javadoc)
-     * 
-     * @see
-     * edu.uci.ics.hyracks.api.dataflow.IOperatorDescriptor#contributeTaskGraph
-     * (edu.uci.ics.hyracks.api.dataflow.IActivityGraphBuilder)
-     */
-    @Override
-    public void contributeTaskGraph(IActivityGraphBuilder builder) {
-        PartialAggregateActivity partialAggAct = new PartialAggregateActivity();
-        MergeActivity mergeAct = new MergeActivity();
-
-        builder.addTask(partialAggAct);
-        builder.addSourceEdge(0, partialAggAct, 0);
-
-        builder.addTask(mergeAct);
-        builder.addTargetEdge(0, mergeAct, 0);
-
-        // FIXME Block or not?
-        builder.addBlockingEdge(partialAggAct, mergeAct);
-
-    }
-
-    private class PartialAggregateActivity extends AbstractActivityNode {
-
-        /**
-         * 
-         */
-        private static final long serialVersionUID = 1L;
-
-        @Override
-        public IOperatorNodePushable createPushRuntime(final IHyracksStageletContext ctx,
-                final IOperatorEnvironment env, final IRecordDescriptorProvider recordDescProvider, int partition,
-                int nPartitions) {
-            // Create the in-memory hash table
-            final SpillableGroupingHashTable gTable = new SpillableGroupingHashTable(ctx, keyFields,
-                    comparatorFactories, tpcf, aggregatorFactory, recordDescProvider.getInputRecordDescriptor(
-                            getOperatorId(), 0), recordDescriptors[0],
-                            // Always take one frame for the input records
-                            framesLimit - 1, tableSize);
-            // Create the tuple accessor
-            final FrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(),
-                    recordDescProvider.getInputRecordDescriptor(getOperatorId(), 0));
-            // Create the partial aggregate activity node
-            IOperatorNodePushable op = new AbstractUnaryInputSinkOperatorNodePushable() {
-
-                /**
-                 * Run files
-                 */
-                private LinkedList<RunFileReader> runs;
-
-                @Override
-                public void close() throws HyracksDataException {
-                    if (gTable.getFrameCount() >= 0) {
-                        if (runs.size() <= 0) {
-                            // All in memory
-                            env.set(GROUPTABLES, gTable);
-                        } else {
-                            // flush the memory into the run file.
-                            flushFramesToRun();
-                        }
-                    }
-                    env.set(RUNS, runs);
-                }
-
-                @Override
-                public void flush() throws HyracksDataException {
-
-                }
-
-                /**
-                 * Process the next input buffer.
-                 * The actual insertion is processed in {@link #gTable}. It will
-                 * check whether it is possible to contain the data into the
-                 * main memory or not. If not, it will indicate the operator to
-                 * flush the content of the table into a run file.
-                 */
-                @Override
-                public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
-                    accessor.reset(buffer);
-                    int tupleCount = accessor.getTupleCount();
-                    for (int i = 0; i < tupleCount; i++) {
-                        // If the group table is too large, flush the table into
-                        // a run file.
-                        if (!gTable.insert(accessor, i)) {
-                            flushFramesToRun();
-                            if (!gTable.insert(accessor, i))
-                                throw new HyracksDataException(
-                                "Failed to insert a new buffer into the aggregate operator!");
-                        }
-                    }
-
-                }
-
-                @Override
-                public void open() throws HyracksDataException {
-                    runs = new LinkedList<RunFileReader>();
-                    gTable.reset();
-                }
-
-                /**
-                 * Flush the content of the group table into a run file.
-                 * During the flushing, the hash table will be sorted as first.
-                 * After that, a run file handler is initialized and the hash
-                 * table is flushed into the run file.
-                 * 
-                 * @throws HyracksDataException
-                 */
-                private void flushFramesToRun() throws HyracksDataException {
-                    // Sort the contents of the hash table.
-                    gTable.sortFrames();
-                    FileReference runFile;
-                    try {
-                        runFile = ctx.getJobletContext().createWorkspaceFile(
-                                ExternalHashGroupOperatorDescriptor.class.getSimpleName());
-                    } catch (IOException e) {
-                        throw new HyracksDataException(e);
-                    }
-                    RunFileWriter writer = new RunFileWriter(runFile, ctx.getIOManager());
-                    writer.open();
-                    try {
-                        gTable.flushFrames(writer, true);
-                    } catch (Exception ex) {
-                        throw new HyracksDataException(ex);
-                    } finally {
-                        writer.close();
-                    }
-                    gTable.reset();
-                    runs.add(((RunFileWriter) writer).createReader());
-                    LOGGER.warning("Created run file: " + runFile.getFile().getAbsolutePath());
-                }
-
-            };
-
-            return op;
-        }
-
-        @Override
-        public IOperatorDescriptor getOwner() {
-            return ExternalHashGroupOperatorDescriptor.this;
-        }
-
-    }
-
-    private class MergeActivity extends AbstractActivityNode {
-
-        /**
-         * 
-         */
-        private static final long serialVersionUID = 1L;
-
-        @Override
-        public IOperatorNodePushable createPushRuntime(final IHyracksStageletContext ctx,
-                final IOperatorEnvironment env, IRecordDescriptorProvider recordDescProvider, int partition,
-                int nPartitions) {
-            final IBinaryComparator[] comparators = new IBinaryComparator[comparatorFactories.length];
-            for (int i = 0; i < comparatorFactories.length; ++i) {
-                comparators[i] = comparatorFactories[i].createBinaryComparator();
-            }
-            IOperatorNodePushable op = new AbstractUnaryOutputSourceOperatorNodePushable() {
-                /**
-                 * Input frames, one for each run file.
-                 */
-                private List<ByteBuffer> inFrames;
-
-                /**
-                 * Output frame.
-                 */
-                private ByteBuffer outFrame;
-
-                /**
-                 * List of the run files to be merged
-                 */
-                LinkedList<RunFileReader> runs;
-
-                /**
-                 * Tuple appender for the output frame {@link #outFrame}.
-                 */
-                private FrameTupleAppender outFrameAppender;
-
-                private ISpillableAccumulatingAggregator visitingAggregator;
-                private ArrayTupleBuilder visitingKeyTuple;
-
-                @SuppressWarnings("unchecked")
-                @Override
-                public void initialize() throws HyracksDataException {
-                    runs = (LinkedList<RunFileReader>) env.get(RUNS);
-                    writer.open();
-
-                    try {
-                        if (runs.size() <= 0) {
-                            // If the aggregate results can be fit into
-                            // memory...
-                            SpillableGroupingHashTable gTable = (SpillableGroupingHashTable) env.get(GROUPTABLES);
-                            if (gTable != null) {
-                                gTable.flushFrames(writer, sortOutput);
-                            }
-                            env.set(GROUPTABLES, null);
-                        } else {
-                            // Otherwise, merge the run files into a single file
-                            inFrames = new ArrayList<ByteBuffer>();
-                            outFrame = ctx.allocateFrame();
-                            outFrameAppender = new FrameTupleAppender(ctx.getFrameSize());
-                            outFrameAppender.reset(outFrame, true);
-                            for (int i = 0; i < framesLimit - 1; ++i) {
-                                inFrames.add(ctx.allocateFrame());
-                            }
-                            int passCount = 0;
-                            while (runs.size() > 0) {
-                                passCount++;
-                                try {
-                                    doPass(runs, passCount);
-                                } catch (Exception e) {
-                                    throw new HyracksDataException(e);
-                                }
-                            }
-                        }
-
-                    } finally {
-                        writer.close();
-                    }
-                    env.set(RUNS, null);
-                }
-
-                /**
-                 * Merge the run files once.
-                 * 
-                 * @param runs
-                 * @param passCount
-                 * @throws HyracksDataException
-                 * @throws IOException
-                 */
-                private void doPass(LinkedList<RunFileReader> runs, int passCount) throws HyracksDataException,
-                IOException {
-                    FileReference newRun = null;
-                    IFrameWriter writer = this.writer;
-                    boolean finalPass = false;
-
-                    int[] storedKeys = new int[keyFields.length];
-                    // Get the list of the fields in the stored records.
-                    for (int i = 0; i < keyFields.length; ++i) {
-                        storedKeys[i] = i;
-                    }
-
-                    // Release the space not used
-                    if (runs.size() + 1 <= framesLimit) {
-                        // If there are run files no more than the available
-                        // frame slots...
-                        // No run file to be generated, since the result can be
-                        // directly
-                        // outputted into the output frame for write.
-                        finalPass = true;
-                        for (int i = inFrames.size() - 1; i >= runs.size(); i--) {
-                            inFrames.remove(i);
-                        }
-                    } else {
-                        // Otherwise, a new run file will be created
-                        newRun = ctx.getJobletContext().createWorkspaceFile(
-                                ExternalHashGroupOperatorDescriptor.class.getSimpleName());
-                        writer = new RunFileWriter(newRun, ctx.getIOManager());
-                        writer.open();
-                    }
-                    try {
-                        // Create run file read handler for each input frame
-                        RunFileReader[] runFileReaders = new RunFileReader[inFrames.size()];
-                        // Create input frame accessor
-                        FrameTupleAccessor[] tupleAccessors = new FrameTupleAccessor[inFrames.size()];
-                        Comparator<ReferenceEntry> comparator = createEntryComparator(comparators);
-                        ReferencedPriorityQueue topTuples = new ReferencedPriorityQueue(ctx.getFrameSize(),
-                                recordDescriptors[0], inFrames.size(), comparator);
-                        // For the index of tuples visited in each frame.
-                        int[] tupleIndexes = new int[inFrames.size()];
-                        for (int i = 0; i < inFrames.size(); i++) {
-                            tupleIndexes[i] = 0;
-                            int runIndex = topTuples.peek().getRunid();
-                            runFileReaders[runIndex] = runs.get(runIndex);
-                            runFileReaders[runIndex].open();
-                            // Load the first frame of the file into the main
-                            // memory
-                            if (runFileReaders[runIndex].nextFrame(inFrames.get(runIndex))) {
-                                // initialize the tuple accessor for the frame
-                                tupleAccessors[runIndex] = new FrameTupleAccessor(ctx.getFrameSize(),
-                                        recordDescriptors[0]);
-                                tupleAccessors[runIndex].reset(inFrames.get(runIndex));
-                                setNextTopTuple(runIndex, tupleIndexes, runFileReaders, tupleAccessors, topTuples);
-                            } else {
-                                closeRun(runIndex, runFileReaders, tupleAccessors);
-                            }
-                        }
-                        // Merge
-                        // Get a key holder for the current working
-                        // aggregator keys
-                        visitingAggregator = null;
-                        visitingKeyTuple = null;
-                        // Loop on all run files, and update the key
-                        // holder.
-                        while (!topTuples.areRunsExhausted()) {
-                            // Get the top record
-                            ReferenceEntry top = topTuples.peek();
-                            int tupleIndex = top.getTupleIndex();
-                            int runIndex = topTuples.peek().getRunid();
-                            FrameTupleAccessor fta = top.getAccessor();
-                            if (visitingAggregator == null) {
-                                // Initialize the aggregator
-                                visitingAggregator = aggregatorFactory.createSpillableAggregator(ctx,
-                                        recordDescriptors[0], recordDescriptors[0]);
-                                // Initialize the partial aggregation result
-                                visitingAggregator.initFromPartial(fta, tupleIndex, keyFields);
-                                visitingKeyTuple = new ArrayTupleBuilder(recordDescriptors[0].getFields().length);
-                                for (int i = 0; i < keyFields.length; i++) {
-                                    visitingKeyTuple.addField(fta, tupleIndex, keyFields[i]);
-                                }
-                            } else {
-                                if (compareTupleWithFrame(visitingKeyTuple, fta, tupleIndex, storedKeys, keyFields,
-                                        comparators) == 0) {
-                                    // If the two partial results are on the
-                                    // same key
-                                    visitingAggregator.accumulatePartialResult(fta, tupleIndex, keyFields);
-                                } else {
-                                    // Otherwise, write the partial result back
-                                    // to the output frame
-                                    if (!visitingAggregator.output(outFrameAppender, visitingKeyTuple)) {
-                                        FrameUtils.flushFrame(outFrame, writer);
-                                        outFrameAppender.reset(outFrame, true);
-                                        if (!visitingAggregator.output(outFrameAppender, visitingKeyTuple)) {
-                                            throw new IllegalStateException();
-                                        }
-                                    }
-                                    // Reset the partial aggregation result
-                                    visitingAggregator.initFromPartial(fta, tupleIndex, keyFields);
-                                    visitingKeyTuple.reset();
-                                    for (int i = 0; i < keyFields.length; i++) {
-                                        visitingKeyTuple.addField(fta, tupleIndex, keyFields[i]);
-                                    }
-                                }
-                            }
-                            tupleIndexes[runIndex]++;
-                            setNextTopTuple(runIndex, tupleIndexes, runFileReaders, tupleAccessors, topTuples);
-                        }
-                        // Output the last aggregation result in the frame
-                        if (visitingAggregator != null) {
-                            if (!visitingAggregator.output(outFrameAppender, visitingKeyTuple)) {
-                                FrameUtils.flushFrame(outFrame, writer);
-                                outFrameAppender.reset(outFrame, true);
-                                if (!visitingAggregator.output(outFrameAppender, visitingKeyTuple)) {
-                                    throw new IllegalStateException();
-                                }
-                            }
-                        }
-                        // Output data into run file writer after all tuples
-                        // have been checked
-                        if (outFrameAppender.getTupleCount() > 0) {
-                            FrameUtils.flushFrame(outFrame, writer);
-                            outFrameAppender.reset(outFrame, true);
-                        }
-                        // empty the input frames
-                        runs.subList(0, inFrames.size()).clear();
-                        // insert the new run file into the beginning of the run
-                        // file list
-                        if (!finalPass) {
-                            runs.add(0, ((RunFileWriter) writer).createReader());
-                        }
-                    } catch (Exception ex) {
-                        throw new HyracksDataException(ex);
-                    } finally {
-                        if (!finalPass) {
-                            writer.close();
-                        }
-                    }
-                }
-
-                /**
-                 * Insert the tuple into the priority queue.
-                 * 
-                 * @param runIndex
-                 * @param tupleIndexes
-                 * @param runCursors
-                 * @param tupleAccessors
-                 * @param topTuples
-                 * @throws IOException
-                 */
-                private void setNextTopTuple(int runIndex, int[] tupleIndexes, RunFileReader[] runCursors,
-                        FrameTupleAccessor[] tupleAccessors, ReferencedPriorityQueue topTuples) throws IOException {
-                    boolean exists = hasNextTuple(runIndex, tupleIndexes, runCursors, tupleAccessors);
-                    if (exists) {
-                        topTuples.popAndReplace(tupleAccessors[runIndex], tupleIndexes[runIndex]);
-                    } else {
-                        topTuples.pop();
-                        closeRun(runIndex, runCursors, tupleAccessors);
-                    }
-                }
-
-                /**
-                 * Check whether there are any more tuples to be checked for the
-                 * given run file from the corresponding input frame.
-                 * If the input frame for this run file is exhausted, load a new
-                 * frame of the run file into the input frame.
-                 * 
-                 * @param runIndex
-                 * @param tupleIndexes
-                 * @param runCursors
-                 * @param tupleAccessors
-                 * @return
-                 * @throws IOException
-                 */
-                private boolean hasNextTuple(int runIndex, int[] tupleIndexes, RunFileReader[] runCursors,
-                        FrameTupleAccessor[] tupleAccessors) throws IOException {
-
-                    if (tupleAccessors[runIndex] == null || runCursors[runIndex] == null) {
-                        /*
-                         * Return false if the targeting run file is not
-                         * available, or the frame for the run file is not
-                         * available.
-                         */
-                        return false;
-                    } else if (tupleIndexes[runIndex] >= tupleAccessors[runIndex].getTupleCount()) {
-                        /*
-                         * If all tuples in the targeting frame have been
-                         * checked.
-                         */
-                        ByteBuffer buf = tupleAccessors[runIndex].getBuffer(); // same-as-inFrames.get(runIndex)
-                        // Refill the buffer with contents from the run file.
-                        if (runCursors[runIndex].nextFrame(buf)) {
-                            tupleIndexes[runIndex] = 0;
-                            return hasNextTuple(runIndex, tupleIndexes, runCursors, tupleAccessors);
-                        } else {
-                            return false;
-                        }
-                    } else {
-                        return true;
-                    }
-                }
-
-                /**
-                 * Close the run file, and also the corresponding readers and
-                 * input frame.
-                 * 
-                 * @param index
-                 * @param runCursors
-                 * @param tupleAccessor
-                 * @throws HyracksDataException
-                 */
-                private void closeRun(int index, RunFileReader[] runCursors, IFrameTupleAccessor[] tupleAccessor)
-                throws HyracksDataException {
-                    runCursors[index].close();
-                    runCursors[index] = null;
-                    tupleAccessor[index] = null;
-                }
-
-                /**
-                 * Compare a tuple (in the format of a {@link ArrayTupleBuilder} ) with a record in a frame (in the format of a {@link FrameTupleAccessor}). Comparing keys and comparators
-                 * are specified for this method as inputs.
-                 * 
-                 * @param tuple0
-                 * @param accessor1
-                 * @param tIndex1
-                 * @param keys0
-                 * @param keys1
-                 * @param comparators
-                 * @return
-                 */
-                private int compareTupleWithFrame(ArrayTupleBuilder tuple0, FrameTupleAccessor accessor1, int tIndex1,
-                        int[] keys0, int[] keys1, IBinaryComparator[] comparators) {
-                    int tStart1 = accessor1.getTupleStartOffset(tIndex1);
-                    int fStartOffset1 = accessor1.getFieldSlotsLength() + tStart1;
-
-                    for (int i = 0; i < keys0.length; ++i) {
-                        int fIdx0 = keys0[i];
-                        int fStart0 = (i == 0 ? 0 : tuple0.getFieldEndOffsets()[fIdx0 - 1]);
-                        int fEnd0 = tuple0.getFieldEndOffsets()[fIdx0];
-                        int fLen0 = fEnd0 - fStart0;
-
-                        int fIdx1 = keys1[i];
-                        int fStart1 = accessor1.getFieldStartOffset(tIndex1, fIdx1);
-                        int fEnd1 = accessor1.getFieldEndOffset(tIndex1, fIdx1);
-                        int fLen1 = fEnd1 - fStart1;
-
-                        int c = comparators[i].compare(tuple0.getByteArray(), fStart0, fLen0, accessor1.getBuffer()
-                                .array(), fStart1 + fStartOffset1, fLen1);
-                        if (c != 0) {
-                            return c;
-                        }
-                    }
-                    return 0;
-                }
-            };
-            return op;
-        }
-
-        @Override
-        public IOperatorDescriptor getOwner() {
-            return ExternalHashGroupOperatorDescriptor.this;
-        }
-
-        private Comparator<ReferenceEntry> createEntryComparator(final IBinaryComparator[] comparators) {
-            return new Comparator<ReferenceEntry>() {
-                public int compare(ReferenceEntry tp1, ReferenceEntry tp2) {
-                    FrameTupleAccessor fta1 = (FrameTupleAccessor) tp1.getAccessor();
-                    FrameTupleAccessor fta2 = (FrameTupleAccessor) tp2.getAccessor();
-                    int j1 = (Integer) tp1.getTupleIndex();
-                    int j2 = (Integer) tp2.getTupleIndex();
-                    byte[] b1 = fta1.getBuffer().array();
-                    byte[] b2 = fta2.getBuffer().array();
-                    for (int f = 0; f < keyFields.length; ++f) {
-                        int fIdx = keyFields[f];
-                        int s1 = fta1.getTupleStartOffset(j1) + fta1.getFieldSlotsLength()
-                        + fta1.getFieldStartOffset(j1, fIdx);
-                        int l1 = fta1.getFieldEndOffset(j1, fIdx) - fta1.getFieldStartOffset(j1, fIdx);
-                        int s2 = fta2.getTupleStartOffset(j2) + fta2.getFieldSlotsLength()
-                        + fta2.getFieldStartOffset(j2, fIdx);
-                        int l2 = fta2.getFieldEndOffset(j2, fIdx) - fta2.getFieldStartOffset(j2, fIdx);
-                        int c = comparators[f].compare(b1, s1, l1, b2, s2, l2);
-                        if (c != 0) {
-                            return c;
-                        }
-                    }
-                    return 0;
-                }
-            };
-        }
-
-    }
-}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/HashSpillableGroupingTableFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/HashSpillableGroupingTableFactory.java
new file mode 100644
index 0000000..3cc2fad
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/HashSpillableGroupingTableFactory.java
@@ -0,0 +1,450 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.group;
+
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.List;
+
+import edu.uci.ics.hyracks.api.comm.IFrameWriter;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputer;
+import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITuplePartitionComputer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITuplePartitionComputerFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTuplePairComparator;
+import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.IAggregatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.IAggregatorDescriptorFactory;
+import edu.uci.ics.hyracks.dataflow.std.structures.ISerializableTable;
+import edu.uci.ics.hyracks.dataflow.std.structures.SerializableHashTable;
+import edu.uci.ics.hyracks.dataflow.std.structures.TuplePointer;
+
+public class HashSpillableGroupingTableFactory implements ISpillableTableFactory {
+    private static final long serialVersionUID = 1L;
+    private final ITuplePartitionComputerFactory tpcf;
+    private final int tableSize;
+
+    public HashSpillableGroupingTableFactory(ITuplePartitionComputerFactory tpcf, int tableSize) {
+        this.tpcf = tpcf;
+        this.tableSize = tableSize;
+    }
+
+    @Override
+    public ISpillableTable buildSpillableTable(final IHyracksStageletContext ctx, final int[] keyFields,
+            final IBinaryComparatorFactory[] comparatorFactories,
+            final INormalizedKeyComputerFactory firstKeyNormalizerFactory,
+            final IAggregatorDescriptorFactory aggregateDescriptorFactory, final RecordDescriptor inRecordDescriptor,
+            final RecordDescriptor outRecordDescriptor, final int framesLimit) throws HyracksDataException {
+        final int[] storedKeys = new int[keyFields.length];
+        @SuppressWarnings("rawtypes")
+        ISerializerDeserializer[] storedKeySerDeser = new ISerializerDeserializer[keyFields.length];
+        for (int i = 0; i < keyFields.length; i++) {
+            storedKeys[i] = i;
+            storedKeySerDeser[i] = inRecordDescriptor.getFields()[keyFields[i]];
+        }
+
+        RecordDescriptor internalRecordDescriptor = outRecordDescriptor;
+        final FrameTupleAccessor storedKeysAccessor1;
+        final FrameTupleAccessor storedKeysAccessor2;
+        if (keyFields.length >= outRecordDescriptor.getFields().length) {
+            // for the case of zero-aggregations
+            ISerializerDeserializer<?>[] fields = outRecordDescriptor.getFields();
+            ITypeTrait[] types = outRecordDescriptor.getTypeTraits();
+            ISerializerDeserializer<?>[] newFields = new ISerializerDeserializer[fields.length + 1];
+            for (int i = 0; i < fields.length; i++)
+                newFields[i] = fields[i];
+            ITypeTrait[] newTypes = null;
+            if (types != null) {
+                newTypes = new ITypeTrait[types.length + 1];
+                for (int i = 0; i < types.length; i++)
+                    newTypes[i] = types[i];
+            }
+            internalRecordDescriptor = new RecordDescriptor(newFields, newTypes);
+        }
+        storedKeysAccessor1 = new FrameTupleAccessor(ctx.getFrameSize(), internalRecordDescriptor);
+        storedKeysAccessor2 = new FrameTupleAccessor(ctx.getFrameSize(), internalRecordDescriptor);
+
+        final IBinaryComparator[] comparators = new IBinaryComparator[comparatorFactories.length];
+        for (int i = 0; i < comparatorFactories.length; ++i) {
+            comparators[i] = comparatorFactories[i].createBinaryComparator();
+        }
+
+        final FrameTuplePairComparator ftpcPartial = new FrameTuplePairComparator(keyFields, storedKeys, comparators);
+        final FrameTuplePairComparator ftpcTuple = new FrameTuplePairComparator(storedKeys, storedKeys, comparators);
+        final FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        final ITuplePartitionComputer tpc = tpcf.createPartitioner();
+        final ByteBuffer outFrame = ctx.allocateFrame();
+
+        final ArrayTupleBuilder internalTupleBuilder;
+        if (keyFields.length < outRecordDescriptor.getFields().length)
+            internalTupleBuilder = new ArrayTupleBuilder(outRecordDescriptor.getFields().length);
+        else
+            internalTupleBuilder = new ArrayTupleBuilder(outRecordDescriptor.getFields().length + 1);
+        final ArrayTupleBuilder outputTupleBuilder = new ArrayTupleBuilder(outRecordDescriptor.getFields().length);
+        final INormalizedKeyComputer nkc = firstKeyNormalizerFactory == null ? null : firstKeyNormalizerFactory
+                .createNormalizedKeyComputer();
+
+        return new ISpillableTable() {
+            private int dataFrameCount;
+            private final ISerializableTable table = new SerializableHashTable(tableSize, ctx);;
+            private final TuplePointer storedTuplePointer = new TuplePointer();
+            private final List<ByteBuffer> frames = new ArrayList<ByteBuffer>();
+            private int groupSize = 0;
+            private IAggregatorDescriptor aggregator = aggregateDescriptorFactory.createAggregator(ctx,
+                    inRecordDescriptor, outRecordDescriptor, keyFields);
+
+            /**
+             * A tuple is "pointed" to by 3 entries in the tPointers array. [0]
+             * = Frame index in the "Frames" list, [1] = Tuple index in the
+             * frame, [2] = Poor man's normalized key for the tuple.
+             */
+            private int[] tPointers;
+
+            @Override
+            public void reset() {
+                groupSize = 0;
+                dataFrameCount = -1;
+                tPointers = null;
+                table.reset();
+                aggregator.close();
+            }
+
+            @Override
+            public boolean insert(FrameTupleAccessor accessor, int tIndex) throws HyracksDataException {
+                if (dataFrameCount < 0)
+                    nextAvailableFrame();
+                int entry = tpc.partition(accessor, tIndex, tableSize);
+                boolean foundGroup = false;
+                int offset = 0;
+                do {
+                    table.getTuplePointer(entry, offset++, storedTuplePointer);
+                    if (storedTuplePointer.frameIndex < 0)
+                        break;
+                    storedKeysAccessor1.reset(frames.get(storedTuplePointer.frameIndex));
+                    int c = ftpcPartial.compare(accessor, tIndex, storedKeysAccessor1, storedTuplePointer.tupleIndex);
+                    if (c == 0) {
+                        foundGroup = true;
+                        break;
+                    }
+                } while (true);
+
+                if (!foundGroup) {
+                    /**
+                     * If no matching group is found, create a new aggregator
+                     * Create a tuple for the new group
+                     */
+                    internalTupleBuilder.reset();
+                    for (int i = 0; i < keyFields.length; i++) {
+                        internalTupleBuilder.addField(accessor, tIndex, keyFields[i]);
+                    }
+                    aggregator.init(accessor, tIndex, internalTupleBuilder);
+                    if (!appender.append(internalTupleBuilder.getFieldEndOffsets(),
+                            internalTupleBuilder.getByteArray(), 0, internalTupleBuilder.getSize())) {
+                        if (!nextAvailableFrame()) {
+                            return false;
+                        } else {
+                            if (!appender.append(internalTupleBuilder.getFieldEndOffsets(),
+                                    internalTupleBuilder.getByteArray(), 0, internalTupleBuilder.getSize())) {
+                                throw new IllegalStateException("Failed to init an aggregator");
+                            }
+                        }
+                    }
+
+                    storedTuplePointer.frameIndex = dataFrameCount;
+                    storedTuplePointer.tupleIndex = appender.getTupleCount() - 1;
+                    table.insert(entry, storedTuplePointer);
+                    groupSize++;
+                } else {
+                    // If there is a matching found, do aggregation directly
+                    int tupleOffset = storedKeysAccessor1.getTupleStartOffset(storedTuplePointer.tupleIndex);
+                    int aggFieldOffset = storedKeysAccessor1.getFieldStartOffset(storedTuplePointer.tupleIndex,
+                            keyFields.length);
+                    int tupleLength = storedKeysAccessor1.getFieldLength(storedTuplePointer.tupleIndex,
+                            keyFields.length);
+                    aggregator.aggregate(accessor, tIndex, storedKeysAccessor1.getBuffer().array(), tupleOffset
+                            + storedKeysAccessor1.getFieldSlotsLength() + aggFieldOffset, tupleLength);
+                }
+                return true;
+            }
+
+            @Override
+            public List<ByteBuffer> getFrames() {
+                return frames;
+            }
+
+            @Override
+            public int getFrameCount() {
+                return dataFrameCount;
+            }
+
+            @Override
+            public void flushFrames(IFrameWriter writer, boolean isPartial) throws HyracksDataException {
+                FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+                writer.open();
+                appender.reset(outFrame, true);
+                if (tPointers == null) {
+                    // Not sorted
+                    for (int i = 0; i < tableSize; ++i) {
+                        int entry = i;
+                        int offset = 0;
+                        do {
+                            table.getTuplePointer(entry, offset++, storedTuplePointer);
+                            if (storedTuplePointer.frameIndex < 0)
+                                break;
+                            int bIndex = storedTuplePointer.frameIndex;
+                            int tIndex = storedTuplePointer.tupleIndex;
+                            storedKeysAccessor1.reset(frames.get(bIndex));
+                            // Reset the tuple for the partial result
+                            outputTupleBuilder.reset();
+                            for (int k = 0; k < keyFields.length; k++) {
+                                outputTupleBuilder.addField(storedKeysAccessor1, tIndex, k);
+                            }
+                            if (isPartial)
+                                aggregator.outputPartialResult(storedKeysAccessor1, tIndex, outputTupleBuilder);
+                            else
+                                aggregator.outputResult(storedKeysAccessor1, tIndex, outputTupleBuilder);
+                            while (!appender.append(outputTupleBuilder.getFieldEndOffsets(),
+                                    outputTupleBuilder.getByteArray(), 0, outputTupleBuilder.getSize())) {
+                                FrameUtils.flushFrame(outFrame, writer);
+                                appender.reset(outFrame, true);
+                            }
+                        } while (true);
+                    }
+                    if (appender.getTupleCount() != 0) {
+                        FrameUtils.flushFrame(outFrame, writer);
+                    }
+                    aggregator.close();
+                    return;
+                }
+                int n = tPointers.length / 3;
+                for (int ptr = 0; ptr < n; ptr++) {
+                    int tableIndex = tPointers[ptr * 3];
+                    int rowIndex = tPointers[ptr * 3 + 1];
+                    table.getTuplePointer(tableIndex, rowIndex, storedTuplePointer);
+                    int frameIndex = storedTuplePointer.frameIndex;
+                    int tupleIndex = storedTuplePointer.tupleIndex;
+                    // Get the frame containing the value
+                    ByteBuffer buffer = frames.get(frameIndex);
+                    storedKeysAccessor1.reset(buffer);
+
+                    outputTupleBuilder.reset();
+                    for (int k = 0; k < keyFields.length; k++) {
+                        outputTupleBuilder.addField(storedKeysAccessor1, tupleIndex, k);
+                    }
+                    if (isPartial)
+                        aggregator.outputPartialResult(storedKeysAccessor1, tupleIndex, outputTupleBuilder);
+                    else
+                        aggregator.outputResult(storedKeysAccessor1, tupleIndex, outputTupleBuilder);
+                    if (!appender.append(outputTupleBuilder.getFieldEndOffsets(), outputTupleBuilder.getByteArray(), 0,
+                            outputTupleBuilder.getSize())) {
+                        FrameUtils.flushFrame(outFrame, writer);
+                        appender.reset(outFrame, true);
+                        if (!appender.append(outputTupleBuilder.getFieldEndOffsets(),
+                                outputTupleBuilder.getByteArray(), 0, outputTupleBuilder.getSize())) {
+                            throw new IllegalStateException();
+                        }
+                    }
+                }
+                if (appender.getTupleCount() > 0) {
+                    FrameUtils.flushFrame(outFrame, writer);
+                }
+                aggregator.close();
+            }
+
+            /**
+             * Set the working frame to the next available frame in the frame
+             * list. There are two cases:<br>
+             * 1) If the next frame is not initialized, allocate a new frame. 2)
+             * When frames are already created, they are recycled.
+             * 
+             * @return Whether a new frame is added successfully.
+             */
+            private boolean nextAvailableFrame() {
+                // Return false if the number of frames is equal to the limit.
+                if (dataFrameCount + 1 >= framesLimit)
+                    return false;
+
+                if (frames.size() < framesLimit) {
+                    // Insert a new frame
+                    ByteBuffer frame = ctx.allocateFrame();
+                    frame.position(0);
+                    frame.limit(frame.capacity());
+                    frames.add(frame);
+                    appender.reset(frame, true);
+                    dataFrameCount = frames.size() - 1;
+                } else {
+                    // Reuse an old frame
+                    dataFrameCount++;
+                    ByteBuffer frame = frames.get(dataFrameCount);
+                    frame.position(0);
+                    frame.limit(frame.capacity());
+                    appender.reset(frame, true);
+                }
+                return true;
+            }
+
+            @Override
+            public void sortFrames() {
+                int sfIdx = storedKeys[0];
+                int totalTCount = table.getTupleCount();
+                tPointers = new int[totalTCount * 3];
+                int ptr = 0;
+
+                for (int i = 0; i < tableSize; i++) {
+                    int entry = i;
+                    int offset = 0;
+                    do {
+                        table.getTuplePointer(entry, offset, storedTuplePointer);
+                        if (storedTuplePointer.frameIndex < 0)
+                            break;
+                        tPointers[ptr * 3] = entry;
+                        tPointers[ptr * 3 + 1] = offset;
+                        table.getTuplePointer(entry, offset, storedTuplePointer);
+                        int fIndex = storedTuplePointer.frameIndex;
+                        int tIndex = storedTuplePointer.tupleIndex;
+                        storedKeysAccessor1.reset(frames.get(fIndex));
+                        int tStart = storedKeysAccessor1.getTupleStartOffset(tIndex);
+                        int f0StartRel = storedKeysAccessor1.getFieldStartOffset(tIndex, sfIdx);
+                        int f0EndRel = storedKeysAccessor1.getFieldEndOffset(tIndex, sfIdx);
+                        int f0Start = f0StartRel + tStart + storedKeysAccessor1.getFieldSlotsLength();
+                        tPointers[ptr * 3 + 2] = nkc == null ? 0 : nkc.normalize(storedKeysAccessor1.getBuffer()
+                                .array(), f0Start, f0EndRel - f0StartRel);
+                        ptr++;
+                        offset++;
+                    } while (true);
+                }
+                /**
+                 * Sort using quick sort
+                 */
+                if (tPointers.length > 0) {
+                    sort(tPointers, 0, totalTCount);
+                }
+            }
+
+            private void sort(int[] tPointers, int offset, int length) {
+                int m = offset + (length >> 1);
+                int mTable = tPointers[m * 3];
+                int mRow = tPointers[m * 3 + 1];
+                int mNormKey = tPointers[m * 3 + 2];
+
+                table.getTuplePointer(mTable, mRow, storedTuplePointer);
+                int mFrame = storedTuplePointer.frameIndex;
+                int mTuple = storedTuplePointer.tupleIndex;
+                storedKeysAccessor1.reset(frames.get(mFrame));
+
+                int a = offset;
+                int b = a;
+                int c = offset + length - 1;
+                int d = c;
+                while (true) {
+                    while (b <= c) {
+                        int bTable = tPointers[b * 3];
+                        int bRow = tPointers[b * 3 + 1];
+                        int bNormKey = tPointers[b * 3 + 2];
+                        int cmp = 0;
+                        if (bNormKey != mNormKey) {
+                            cmp = ((((long) bNormKey) & 0xffffffffL) < (((long) mNormKey) & 0xffffffffL)) ? -1 : 1;
+                        } else {
+                            table.getTuplePointer(bTable, bRow, storedTuplePointer);
+                            int bFrame = storedTuplePointer.frameIndex;
+                            int bTuple = storedTuplePointer.tupleIndex;
+                            storedKeysAccessor2.reset(frames.get(bFrame));
+                            cmp = ftpcTuple.compare(storedKeysAccessor2, bTuple, storedKeysAccessor1, mTuple);
+                        }
+                        if (cmp > 0) {
+                            break;
+                        }
+                        if (cmp == 0) {
+                            swap(tPointers, a++, b);
+                        }
+                        ++b;
+                    }
+                    while (c >= b) {
+                        int cTable = tPointers[c * 3];
+                        int cRow = tPointers[c * 3 + 1];
+                        int cNormKey = tPointers[c * 3 + 2];
+                        int cmp = 0;
+                        if (cNormKey != mNormKey) {
+                            cmp = ((((long) cNormKey) & 0xffffffffL) < (((long) mNormKey) & 0xffffffffL)) ? -1 : 1;
+                        } else {
+                            table.getTuplePointer(cTable, cRow, storedTuplePointer);
+                            int cFrame = storedTuplePointer.frameIndex;
+                            int cTuple = storedTuplePointer.tupleIndex;
+                            storedKeysAccessor2.reset(frames.get(cFrame));
+                            cmp = ftpcTuple.compare(storedKeysAccessor2, cTuple, storedKeysAccessor1, mTuple);
+                        }
+                        if (cmp < 0) {
+                            break;
+                        }
+                        if (cmp == 0) {
+                            swap(tPointers, c, d--);
+                        }
+                        --c;
+                    }
+                    if (b > c)
+                        break;
+                    swap(tPointers, b++, c--);
+                }
+
+                int s;
+                int n = offset + length;
+                s = Math.min(a - offset, b - a);
+                vecswap(tPointers, offset, b - s, s);
+                s = Math.min(d - c, n - d - 1);
+                vecswap(tPointers, b, n - s, s);
+
+                if ((s = b - a) > 1) {
+                    sort(tPointers, offset, s);
+                }
+                if ((s = d - c) > 1) {
+                    sort(tPointers, n - s, s);
+                }
+            }
+
+            private void swap(int x[], int a, int b) {
+                for (int i = 0; i < 3; ++i) {
+                    int t = x[a * 3 + i];
+                    x[a * 3 + i] = x[b * 3 + i];
+                    x[b * 3 + i] = t;
+                }
+            }
+
+            private void vecswap(int x[], int a, int b, int n) {
+                for (int i = 0; i < n; i++, a++, b++) {
+                    swap(x, a, b);
+                }
+            }
+
+            @Override
+            public void close() {
+                groupSize = 0;
+                dataFrameCount = -1;
+                tPointers = null;
+                table.close();
+                frames.clear();
+            }
+        };
+    }
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/IAccumulatingAggregatorFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/IAccumulatingAggregatorFactory.java
index 3fc7d79..8eff82f 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/IAccumulatingAggregatorFactory.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/IAccumulatingAggregatorFactory.java
@@ -24,6 +24,4 @@
     IAccumulatingAggregator createAggregator(IHyracksStageletContext ctx, RecordDescriptor inRecordDesc,
             RecordDescriptor outRecordDescriptor) throws HyracksDataException;
 
-    ISpillableAccumulatingAggregator createSpillableAggregator(IHyracksStageletContext ctx,
-            RecordDescriptor inRecordDesc, RecordDescriptor outRecordDescriptor) throws HyracksDataException;
 }
\ No newline at end of file
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ISpillableAccumulatingAggregator.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ISpillableAccumulatingAggregator.java
deleted file mode 100644
index 59c69eb..0000000
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ISpillableAccumulatingAggregator.java
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package edu.uci.ics.hyracks.dataflow.std.group;
-
-import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
-import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
-
-/**
- * An spillable version of the {@link IAccumulatingAggregator} supporting
- * external aggregation.
- */
-public interface ISpillableAccumulatingAggregator extends IAccumulatingAggregator {
-
-    public void initFromPartial(IFrameTupleAccessor accessor, int tIndex, int[] keyFieldIndexes)
-    throws HyracksDataException;
-
-    /**
-     * @param accessor
-     * @param tIndex
-     * @throws HyracksDataException
-     */
-    public void accumulatePartialResult(IFrameTupleAccessor accessor, int tIndex, int[] keyFieldIndexes)
-    throws HyracksDataException;
-
-    public boolean output(FrameTupleAppender appender, ArrayTupleBuilder tbder) throws HyracksDataException;
-}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ISpillableTable.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ISpillableTable.java
new file mode 100644
index 0000000..7bd8cd8
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ISpillableTable.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.group;
+
+import java.nio.ByteBuffer;
+import java.util.List;
+
+import edu.uci.ics.hyracks.api.comm.IFrameWriter;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+
+/**
+ * @author jarodwen
+ */
+public interface ISpillableTable {
+
+    public void close();
+
+    public void reset();
+
+    public int getFrameCount();
+
+    public List<ByteBuffer> getFrames();
+
+    public void sortFrames();
+
+    public boolean insert(FrameTupleAccessor accessor, int tIndex) throws HyracksDataException;
+
+    public void flushFrames(IFrameWriter writer, boolean isPartial) throws HyracksDataException;
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ISpillableTableFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ISpillableTableFactory.java
new file mode 100644
index 0000000..07f0ac0
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/ISpillableTableFactory.java
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.dataflow.std.group;
+
+import java.io.Serializable;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.IAggregatorDescriptorFactory;
+
+/**
+ * @author jarodwen
+ */
+public interface ISpillableTableFactory extends Serializable {
+    ISpillableTable buildSpillableTable(IHyracksStageletContext ctx, int[] keyFields,
+            IBinaryComparatorFactory[] comparatorFactories, INormalizedKeyComputerFactory normalizedKeyComputerFactory,
+            IAggregatorDescriptorFactory aggregatorFactory, RecordDescriptor inRecordDescriptor,
+            RecordDescriptor outRecordDescriptor, int framesLimit) throws HyracksDataException;
+
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/SpillableGroupingHashTable.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/SpillableGroupingHashTable.java
deleted file mode 100644
index b3b9f24..0000000
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/SpillableGroupingHashTable.java
+++ /dev/null
@@ -1,569 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package edu.uci.ics.hyracks.dataflow.std.group;
-
-import java.nio.ByteBuffer;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
-
-import edu.uci.ics.hyracks.api.comm.IFrameWriter;
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
-import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
-import edu.uci.ics.hyracks.api.dataflow.value.ITuplePartitionComputer;
-import edu.uci.ics.hyracks.api.dataflow.value.ITuplePartitionComputerFactory;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTuplePairComparator;
-import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
-
-/**
- * An in-mem hash table for spillable grouping operations.
- * A table of {@link #Link}s are maintained in this object, and each row
- * of this table represents a hash partition.
- */
-public class SpillableGroupingHashTable {
-
-    /**
-     * Context.
-     */
-    private final IHyracksStageletContext ctx;
-
-    /**
-     * Columns for group-by
-     */
-    private final int[] fields;
-
-    /**
-     * Key fields of records in the hash table (starting from 0
-     * to the number of the key fields).
-     * This is different from the key fields in the input records,
-     * since these fields are extracted when being inserted into
-     * the hash table.
-     */
-    private final int[] storedKeys;
-
-    /**
-     * Comparators: one for each column in {@link #groupFields}
-     */
-    private final IBinaryComparator[] comparators;
-
-    /**
-     * Record descriptor for the input tuple.
-     */
-    private final RecordDescriptor inRecordDescriptor;
-
-    /**
-     * Record descriptor for the partial aggregation result.
-     */
-    private final RecordDescriptor outputRecordDescriptor;
-
-    /**
-     * Accumulators in the main memory.
-     */
-    private ISpillableAccumulatingAggregator[] accumulators;
-
-    /**
-     * The hashing group table containing pointers to aggregators and also the
-     * corresponding key tuples. So for each entry, there will be three integer
-     * fields:
-     * 1. The frame index containing the key tuple; 2. The tuple index inside of
-     * the frame for the key tuple; 3. The index of the aggregator.
-     * Note that each link in the table is a partition for the input records. Multiple
-     * records in the same partition based on the {@link #tpc} are stored as
-     * pointers.
-     */
-    private final Link[] table;
-
-    /**
-     * Number of accumulators.
-     */
-    private int accumulatorSize = 0;
-
-    /**
-     * Factory for the aggregators.
-     */
-    private final IAccumulatingAggregatorFactory aggregatorFactory;
-
-    private final List<ByteBuffer> frames;
-
-    private final ByteBuffer outFrame;
-
-    /**
-     * Frame appender for output frames in {@link #frames}.
-     */
-    private final FrameTupleAppender appender;
-
-    /**
-     * The count of used frames in the table.
-     * Note that this cannot be replaced by {@link #frames} since frames will
-     * not be removed after being created.
-     */
-    private int dataFrameCount;
-
-    /**
-     * Pointers for the sorted aggregators
-     */
-    private int[] tPointers;
-
-    private static final int INIT_ACCUMULATORS_SIZE = 8;
-
-    /**
-     * The maximum number of frames available for this hashing group table.
-     */
-    private final int framesLimit;
-
-    private final FrameTuplePairComparator ftpc;
-
-    /**
-     * A partition computer to partition the hashing group table.
-     */
-    private final ITuplePartitionComputer tpc;
-
-    /**
-     * Accessors for the tuples. Two accessors are necessary during the sort.
-     */
-    private final FrameTupleAccessor storedKeysAccessor1;
-    private final FrameTupleAccessor storedKeysAccessor2;
-
-    /**
-     * Create a spillable grouping hash table.
-     * 
-     * @param ctx
-     *            The context of the job.
-     * @param fields
-     *            Fields of keys for grouping.
-     * @param comparatorFactories
-     *            The comparators.
-     * @param tpcf
-     *            The partitioners. These are used to partition the incoming records into proper partition of the hash table.
-     * @param aggregatorFactory
-     *            The aggregators.
-     * @param inRecordDescriptor
-     *            Record descriptor for input data.
-     * @param outputRecordDescriptor
-     *            Record descriptor for output data.
-     * @param framesLimit
-     *            The maximum number of frames usable in the memory for hash table.
-     * @param tableSize
-     *            The size of the table, which specified the number of partitions of the table.
-     */
-    public SpillableGroupingHashTable(IHyracksStageletContext ctx, int[] fields,
-            IBinaryComparatorFactory[] comparatorFactories, ITuplePartitionComputerFactory tpcf,
-            IAccumulatingAggregatorFactory aggregatorFactory, RecordDescriptor inRecordDescriptor,
-            RecordDescriptor outputRecordDescriptor, int framesLimit, int tableSize) {
-        this.ctx = ctx;
-        this.fields = fields;
-
-        storedKeys = new int[fields.length];
-        @SuppressWarnings("rawtypes")
-        ISerializerDeserializer[] storedKeySerDeser = new ISerializerDeserializer[fields.length];
-
-        // Note that after storing a record into the hash table, the index for the fields should
-        // be updated. Here we assume that all these key fields are written at the beginning of 
-        // the record, so their index should start from 0 and end at the length of the key fields.
-        for (int i = 0; i < fields.length; ++i) {
-            storedKeys[i] = i;
-            storedKeySerDeser[i] = inRecordDescriptor.getFields()[fields[i]];
-        }
-        RecordDescriptor storedKeysRecordDescriptor = new RecordDescriptor(storedKeySerDeser);
-        storedKeysAccessor1 = new FrameTupleAccessor(ctx.getFrameSize(), storedKeysRecordDescriptor);
-        storedKeysAccessor2 = new FrameTupleAccessor(ctx.getFrameSize(), storedKeysRecordDescriptor);
-
-        comparators = new IBinaryComparator[comparatorFactories.length];
-        for (int i = 0; i < comparatorFactories.length; ++i) {
-            comparators[i] = comparatorFactories[i].createBinaryComparator();
-        }
-
-        this.table = new Link[tableSize];
-
-        this.aggregatorFactory = aggregatorFactory;
-        accumulators = new ISpillableAccumulatingAggregator[INIT_ACCUMULATORS_SIZE];
-
-        this.framesLimit = framesLimit;
-
-        // Tuple pair comparator
-        ftpc = new FrameTuplePairComparator(fields, storedKeys, comparators);
-
-        // Partitioner
-        tpc = tpcf.createPartitioner();
-
-        this.inRecordDescriptor = inRecordDescriptor;
-        this.outputRecordDescriptor = outputRecordDescriptor;
-        frames = new ArrayList<ByteBuffer>();
-        appender = new FrameTupleAppender(ctx.getFrameSize());
-
-        dataFrameCount = -1;
-
-        outFrame = ctx.allocateFrame();
-    }
-
-    public void reset() {
-        dataFrameCount = -1;
-        tPointers = null;
-        // Reset the grouping hash table
-        for (int i = 0; i < table.length; i++) {
-            table[i] = new Link();
-        }
-    }
-
-    public int getFrameCount() {
-        return dataFrameCount;
-    }
-
-    /**
-     * How to define pointers for the partial aggregation
-     * 
-     * @return
-     */
-    public int[] getTPointers() {
-        return tPointers;
-    }
-
-    /**
-     * Redefine the number of fields in the pointer.
-     * Only two pointers are necessary for external grouping: one is to the
-     * index of the hash table, and the other is to the row index inside of the
-     * hash table.
-     * 
-     * @return
-     */
-    public int getPtrFields() {
-        return 2;
-    }
-
-    public List<ByteBuffer> getFrames() {
-        return frames;
-    }
-
-    /**
-     * Set the working frame to the next available frame in the
-     * frame list. There are two cases:<br>
-     * 1) If the next frame is not initialized, allocate
-     * a new frame.
-     * 2) When frames are already created, they are recycled.
-     * 
-     * @return Whether a new frame is added successfully.
-     */
-    private boolean nextAvailableFrame() {
-        // Return false if the number of frames is equal to the limit.
-        if (dataFrameCount + 1 >= framesLimit)
-            return false;
-
-        if (frames.size() < framesLimit) {
-            // Insert a new frame
-            ByteBuffer frame = ctx.allocateFrame();
-            frame.position(0);
-            frame.limit(frame.capacity());
-            frames.add(frame);
-            appender.reset(frame, true);
-            dataFrameCount++;
-        } else {
-            // Reuse an old frame
-            dataFrameCount++;
-            ByteBuffer frame = frames.get(dataFrameCount);
-            frame.position(0);
-            frame.limit(frame.capacity());
-            appender.reset(frame, true);
-        }
-        return true;
-    }
-
-    /**
-     * Insert a new record from the input frame.
-     * 
-     * @param accessor
-     * @param tIndex
-     * @return
-     * @throws HyracksDataException
-     */
-    public boolean insert(FrameTupleAccessor accessor, int tIndex) throws HyracksDataException {
-        if (dataFrameCount < 0)
-            nextAvailableFrame();
-        // Get the partition for the inserting tuple
-        int entry = tpc.partition(accessor, tIndex, table.length);
-        Link link = table[entry];
-        if (link == null) {
-            link = table[entry] = new Link();
-        }
-        // Find the corresponding aggregator from existing aggregators
-        ISpillableAccumulatingAggregator aggregator = null;
-        for (int i = 0; i < link.size; i += 3) {
-            int sbIndex = link.pointers[i];
-            int stIndex = link.pointers[i + 1];
-            int saIndex = link.pointers[i + 2];
-            storedKeysAccessor1.reset(frames.get(sbIndex));
-            int c = ftpc.compare(accessor, tIndex, storedKeysAccessor1, stIndex);
-            if (c == 0) {
-                aggregator = accumulators[saIndex];
-                break;
-            }
-        }
-        // Do insert
-        if (aggregator == null) {
-            // Did not find the aggregator. Insert a new aggregator entry
-            if (!appender.appendProjection(accessor, tIndex, fields)) {
-                if (!nextAvailableFrame()) {
-                    // If buffer is full, return false to trigger a run file
-                    // write
-                    return false;
-                } else {
-                    // Try to do insert after adding a new frame.
-                    if (!appender.appendProjection(accessor, tIndex, fields)) {
-                        throw new IllegalStateException();
-                    }
-                }
-            }
-            int sbIndex = dataFrameCount;
-            int stIndex = appender.getTupleCount() - 1;
-            if (accumulatorSize >= accumulators.length) {
-                accumulators = Arrays.copyOf(accumulators, accumulators.length * 2);
-            }
-            int saIndex = accumulatorSize++;
-            aggregator = accumulators[saIndex] = aggregatorFactory.createSpillableAggregator(ctx, inRecordDescriptor,
-                    outputRecordDescriptor);
-            aggregator.init(accessor, tIndex);
-            link.add(sbIndex, stIndex, saIndex);
-        }
-        aggregator.accumulate(accessor, tIndex);
-        return true;
-    }
-
-    /**
-     * Sort partial results
-     */
-    public void sortFrames() {
-        int totalTCount = 0;
-        // Get the number of records
-        for (int i = 0; i < table.length; i++) {
-            if (table[i] == null)
-                continue;
-            totalTCount += table[i].size / 3;
-        }
-        // Start sorting:
-        /*
-         * Based on the data structure for the partial aggregates, the
-         * pointers should be initialized.
-         */
-        tPointers = new int[totalTCount * getPtrFields()];
-        // Initialize pointers
-        int ptr = 0;
-        // Maintain two pointers to each entry of the hashing group table
-        for (int i = 0; i < table.length; i++) {
-            if (table[i] == null)
-                continue;
-            for (int j = 0; j < table[i].size; j = j + 3) {
-                tPointers[ptr * getPtrFields()] = i;
-                tPointers[ptr * getPtrFields() + 1] = j;
-                ptr++;
-            }
-        }
-        // Sort using quick sort
-        if (tPointers.length > 0) {
-            sort(tPointers, 0, totalTCount);
-        }
-    }
-
-    /**
-     * @param writer
-     * @throws HyracksDataException
-     */
-    public void flushFrames(IFrameWriter writer, boolean sorted) throws HyracksDataException {
-        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
-
-        ISpillableAccumulatingAggregator aggregator = null;
-        writer.open();
-        appender.reset(outFrame, true);
-        if (sorted) {
-            sortFrames();
-        }
-        if (tPointers == null) {
-            // Not sorted
-            for (int i = 0; i < table.length; ++i) {
-                Link link = table[i];
-                if (link != null) {
-                    for (int j = 0; j < link.size; j += 3) {
-                        int bIndex = link.pointers[j];
-                        int tIndex = link.pointers[j + 1];
-                        int aIndex = link.pointers[j + 2];
-                        ByteBuffer keyBuffer = frames.get(bIndex);
-                        storedKeysAccessor1.reset(keyBuffer);
-                        aggregator = accumulators[aIndex];
-                        while (!aggregator.output(appender, storedKeysAccessor1, tIndex, storedKeys)) {
-                            FrameUtils.flushFrame(outFrame, writer);
-                            appender.reset(outFrame, true);
-                        }
-                    }
-                }
-            }
-            if (appender.getTupleCount() != 0) {
-                FrameUtils.flushFrame(outFrame, writer);
-            }
-            return;
-        }
-        int n = tPointers.length / getPtrFields();
-        for (int ptr = 0; ptr < n; ptr++) {
-            int tableIndex = tPointers[ptr * 2];
-            int rowIndex = tPointers[ptr * 2 + 1];
-            int frameIndex = table[tableIndex].pointers[rowIndex];
-            int tupleIndex = table[tableIndex].pointers[rowIndex + 1];
-            int aggregatorIndex = table[tableIndex].pointers[rowIndex + 2];
-            // Get the frame containing the value
-            ByteBuffer buffer = frames.get(frameIndex);
-            storedKeysAccessor1.reset(buffer);
-
-            // Get the aggregator
-            aggregator = accumulators[aggregatorIndex];
-            // Insert
-            if (!aggregator.output(appender, storedKeysAccessor1, tupleIndex, fields)) {
-                FrameUtils.flushFrame(outFrame, writer);
-                appender.reset(outFrame, true);
-                if (!aggregator.output(appender, storedKeysAccessor1, tupleIndex, fields)) {
-                    throw new IllegalStateException();
-                } else {
-                    accumulators[aggregatorIndex] = null;
-                }
-            } else {
-                accumulators[aggregatorIndex] = null;
-            }
-        }
-        if (appender.getTupleCount() > 0) {
-            FrameUtils.flushFrame(outFrame, writer);
-        }
-    }
-
-    private void sort(int[] tPointers, int offset, int length) {
-        int m = offset + (length >> 1);
-        // Get table index
-        int mTable = tPointers[m * 2];
-        int mRow = tPointers[m * 2 + 1];
-        // Get frame and tuple index
-        int mFrame = table[mTable].pointers[mRow];
-        int mTuple = table[mTable].pointers[mRow + 1];
-        storedKeysAccessor1.reset(frames.get(mFrame));
-
-        int a = offset;
-        int b = a;
-        int c = offset + length - 1;
-        int d = c;
-        while (true) {
-            while (b <= c) {
-                int bTable = tPointers[b * 2];
-                int bRow = tPointers[b * 2 + 1];
-                int bFrame = table[bTable].pointers[bRow];
-                int bTuple = table[bTable].pointers[bRow + 1];
-                storedKeysAccessor2.reset(frames.get(bFrame));
-                int cmp = ftpc.compare(storedKeysAccessor2, bTuple, storedKeysAccessor1, mTuple);
-                // int cmp = compare(tPointers, b, mi, mj, mv);
-                if (cmp > 0) {
-                    break;
-                }
-                if (cmp == 0) {
-                    swap(tPointers, a++, b);
-                }
-                ++b;
-            }
-            while (c >= b) {
-                int cTable = tPointers[c * 2];
-                int cRow = tPointers[c * 2 + 1];
-                int cFrame = table[cTable].pointers[cRow];
-                int cTuple = table[cTable].pointers[cRow + 1];
-                storedKeysAccessor2.reset(frames.get(cFrame));
-                int cmp = ftpc.compare(storedKeysAccessor2, cTuple, storedKeysAccessor1, mTuple);
-                // int cmp = compare(tPointers, c, mi, mj, mv);
-                if (cmp < 0) {
-                    break;
-                }
-                if (cmp == 0) {
-                    swap(tPointers, c, d--);
-                }
-                --c;
-            }
-            if (b > c)
-                break;
-            swap(tPointers, b++, c--);
-        }
-
-        int s;
-        int n = offset + length;
-        s = Math.min(a - offset, b - a);
-        vecswap(tPointers, offset, b - s, s);
-        s = Math.min(d - c, n - d - 1);
-        vecswap(tPointers, b, n - s, s);
-
-        if ((s = b - a) > 1) {
-            sort(tPointers, offset, s);
-        }
-        if ((s = d - c) > 1) {
-            sort(tPointers, n - s, s);
-        }
-    }
-
-    private void swap(int x[], int a, int b) {
-        for (int i = 0; i < 2; ++i) {
-            int t = x[a * 2 + i];
-            x[a * 2 + i] = x[b * 2 + i];
-            x[b * 2 + i] = t;
-        }
-    }
-
-    private void vecswap(int x[], int a, int b, int n) {
-        for (int i = 0; i < n; i++, a++, b++) {
-            swap(x, a, b);
-        }
-    }
-
-    /**
-     * The pointers in the link store 3 int values for each entry in the
-     * hashtable: (bufferIdx, tIndex, accumulatorIdx).
-     * 
-     * @author vinayakb
-     */
-    private static class Link {
-        private static final int INIT_POINTERS_SIZE = 9;
-
-        int[] pointers;
-        int size;
-
-        Link() {
-            pointers = new int[INIT_POINTERS_SIZE];
-            size = 0;
-        }
-
-        void add(int bufferIdx, int tIndex, int accumulatorIdx) {
-            while (size + 3 > pointers.length) {
-                pointers = Arrays.copyOf(pointers, pointers.length * 2);
-            }
-            pointers[size++] = bufferIdx;
-            pointers[size++] = tIndex;
-            pointers[size++] = accumulatorIdx;
-        }
-
-        public String toString() {
-            StringBuilder sb = new StringBuilder();
-            sb.append("[Size=" + size + "]");
-            for (int i = 0; i < pointers.length; i = i + 3) {
-                sb.append(pointers[i] + ",");
-                sb.append(pointers[i + 1] + ",");
-                sb.append(pointers[i + 2] + "; ");
-            }
-            return sb.toString();
-        }
-    }
-}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/join/InMemoryHashJoin.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/join/InMemoryHashJoin.java
index 94a9501..d1d528c 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/join/InMemoryHashJoin.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/join/InMemoryHashJoin.java
@@ -42,7 +42,7 @@
     private final ByteBuffer outBuffer;
     private final boolean isLeftOuter;
     private final ArrayTupleBuilder nullTupleBuild;
-    
+
     public InMemoryHashJoin(IHyracksStageletContext ctx, int tableSize, FrameTupleAccessor accessor0,
             ITuplePartitionComputer tpc0, FrameTupleAccessor accessor1, ITuplePartitionComputer tpc1,
             FrameTuplePairComparator comparator, boolean isLeftOuter, INullWriter[] nullWriters1)
@@ -57,7 +57,7 @@
         tpComparator = comparator;
         outBuffer = ctx.allocateFrame();
         appender.reset(outBuffer, true);
-        this.isLeftOuter = isLeftOuter;        
+        this.isLeftOuter = isLeftOuter;
         if (isLeftOuter) {
             int fieldCountOuter = accessor1.getFieldCount();
             nullTupleBuild = new ArrayTupleBuilder(fieldCountOuter);
@@ -114,13 +114,14 @@
                 }
             }
             if (!matchFound && isLeftOuter) {
-                if (!appender.appendConcat(accessorProbe, i, nullTupleBuild.getFieldEndOffsets(), nullTupleBuild.getByteArray(), 0, nullTupleBuild.getSize())) {
+                if (!appender.appendConcat(accessorProbe, i, nullTupleBuild.getFieldEndOffsets(),
+                        nullTupleBuild.getByteArray(), 0, nullTupleBuild.getSize())) {
                     flushFrame(outBuffer, writer);
                     appender.reset(outBuffer, true);
-                    if (!appender.appendConcat(accessorProbe, i, nullTupleBuild.getFieldEndOffsets(), nullTupleBuild.getByteArray(), 0, nullTupleBuild
-                            .getSize())) {
+                    if (!appender.appendConcat(accessorProbe, i, nullTupleBuild.getFieldEndOffsets(),
+                            nullTupleBuild.getByteArray(), 0, nullTupleBuild.getSize())) {
                         throw new IllegalStateException();
-                    }                  
+                    }
                 }
             }
         }
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/misc/PrinterOperatorDescriptor.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/misc/PrinterOperatorDescriptor.java
index 7f097e0..e44e8a9 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/misc/PrinterOperatorDescriptor.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/misc/PrinterOperatorDescriptor.java
@@ -24,6 +24,7 @@
 import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.base.IOpenableDataWriterOperator;
 import edu.uci.ics.hyracks.dataflow.std.util.DeserializedOperatorNodePushable;
+import edu.uci.ics.hyracks.dataflow.std.util.StringSerializationUtils;
 
 public class PrinterOperatorDescriptor extends AbstractSingleActivityOperatorDescriptor {
     private static final long serialVersionUID = 1L;
@@ -44,7 +45,7 @@
         @Override
         public void writeData(Object[] data) throws HyracksDataException {
             for (int i = 0; i < data.length; ++i) {
-                System.err.print(String.valueOf(data[i]));
+                System.err.print(StringSerializationUtils.toString(data[i]));
                 System.err.print(", ");
             }
             System.err.println();
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/sort/FrameSorter.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/sort/FrameSorter.java
index 3742e91..710ef38 100644
--- a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/sort/FrameSorter.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/sort/FrameSorter.java
@@ -35,14 +35,18 @@
     private final int[] sortFields;
     private final INormalizedKeyComputer nkc;
     private final IBinaryComparator[] comparators;
-    private final RecordDescriptor recordDescriptor;
     private final List<ByteBuffer> buffers;
 
     private final FrameTupleAccessor fta1;
     private final FrameTupleAccessor fta2;
 
+    private final FrameTupleAppender appender;
+
+    private final ByteBuffer outFrame;
+
     private int dataFrameCount;
     private int[] tPointers;
+    private int tupleCount;
 
     public FrameSorter(IHyracksCommonContext ctx, int[] sortFields,
             INormalizedKeyComputerFactory firstKeyNormalizerFactory, IBinaryComparatorFactory[] comparatorFactories,
@@ -54,39 +58,24 @@
         for (int i = 0; i < comparatorFactories.length; ++i) {
             comparators[i] = comparatorFactories[i].createBinaryComparator();
         }
-        this.recordDescriptor = recordDescriptor;
         buffers = new ArrayList<ByteBuffer>();
         fta1 = new FrameTupleAccessor(ctx.getFrameSize(), recordDescriptor);
         fta2 = new FrameTupleAccessor(ctx.getFrameSize(), recordDescriptor);
+        appender = new FrameTupleAppender(ctx.getFrameSize());
+        outFrame = ctx.allocateFrame();
 
         dataFrameCount = 0;
     }
 
     public void reset() {
         dataFrameCount = 0;
-        tPointers = null;
+        tupleCount = 0;
     }
 
     public int getFrameCount() {
         return dataFrameCount;
     }
 
-    /**
-     * Gets the sorted tuple pointers.
-     * A tuple is "pointed" to by 4 entries in the tPointers array.
-     * [0] = Frame index in the "Frames" list.
-     * [1] = Start offset of the tuple in the frame
-     * [2] = Length of the tuple
-     * [3] = Poor man's normalized key for the tuple.
-     */
-    public int[] getTPointers() {
-        return tPointers;
-    }
-
-    public List<ByteBuffer> getFrames() {
-        return buffers;
-    }
-
     public void insertFrame(ByteBuffer buffer) {
         ByteBuffer copyFrame;
         if (dataFrameCount == buffers.size()) {
@@ -100,55 +89,50 @@
     }
 
     public void sortFrames() {
-        FrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recordDescriptor);
         int nBuffers = dataFrameCount;
-        int totalTCount = 0;
+        tupleCount = 0;
         for (int i = 0; i < nBuffers; ++i) {
-            accessor.reset(buffers.get(i));
-            totalTCount += accessor.getTupleCount();
+            fta1.reset(buffers.get(i));
+            tupleCount += fta1.getTupleCount();
         }
         int sfIdx = sortFields[0];
-        tPointers = new int[totalTCount * 4];
+        tPointers = tPointers == null || tPointers.length < tupleCount * 4 ? new int[tupleCount * 4] : tPointers;
         int ptr = 0;
         for (int i = 0; i < nBuffers; ++i) {
-            accessor.reset(buffers.get(i));
-            int tCount = accessor.getTupleCount();
-            byte[] array = accessor.getBuffer().array();
+            fta1.reset(buffers.get(i));
+            int tCount = fta1.getTupleCount();
+            byte[] array = fta1.getBuffer().array();
             for (int j = 0; j < tCount; ++j) {
-                int tStart = accessor.getTupleStartOffset(j);
-                int tEnd = accessor.getTupleEndOffset(j);
+                int tStart = fta1.getTupleStartOffset(j);
+                int tEnd = fta1.getTupleEndOffset(j);
                 tPointers[ptr * 4] = i;
                 tPointers[ptr * 4 + 1] = tStart;
                 tPointers[ptr * 4 + 2] = tEnd;
-                int f0StartRel = accessor.getFieldStartOffset(j, sfIdx);
-                int f0EndRel = accessor.getFieldEndOffset(j, sfIdx);
-                int f0Start = f0StartRel + tStart + accessor.getFieldSlotsLength();
+                int f0StartRel = fta1.getFieldStartOffset(j, sfIdx);
+                int f0EndRel = fta1.getFieldEndOffset(j, sfIdx);
+                int f0Start = f0StartRel + tStart + fta1.getFieldSlotsLength();
                 tPointers[ptr * 4 + 3] = nkc == null ? 0 : nkc.normalize(array, f0Start, f0EndRel - f0StartRel);
                 ++ptr;
             }
         }
-        if (tPointers.length > 0) {
-            sort(tPointers, 0, totalTCount);
+        if (tupleCount > 0) {
+            sort(tPointers, 0, tupleCount);
         }
     }
 
     public void flushFrames(IFrameWriter writer) throws HyracksDataException {
-        FrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recordDescriptor);
-        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
-        ByteBuffer outFrame = ctx.allocateFrame();
         writer.open();
         appender.reset(outFrame, true);
-        int n = tPointers.length / 4;
-        for (int ptr = 0; ptr < n; ++ptr) {
+        for (int ptr = 0; ptr < tupleCount; ++ptr) {
             int i = tPointers[ptr * 4];
             int tStart = tPointers[ptr * 4 + 1];
             int tEnd = tPointers[ptr * 4 + 2];
             ByteBuffer buffer = buffers.get(i);
-            accessor.reset(buffer);
-            if (!appender.append(accessor, tStart, tEnd)) {
+            fta1.reset(buffer);
+            if (!appender.append(fta1, tStart, tEnd)) {
                 FrameUtils.flushFrame(outFrame, writer);
                 appender.reset(outFrame, true);
-                if (!appender.append(accessor, tStart, tEnd)) {
+                if (!appender.append(fta1, tStart, tEnd)) {
                     throw new IllegalStateException();
                 }
             }
@@ -255,4 +239,4 @@
         }
         return 0;
     }
-}
+}
\ No newline at end of file
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/structures/ISerializableTable.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/structures/ISerializableTable.java
new file mode 100644
index 0000000..7dc0b17
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/structures/ISerializableTable.java
@@ -0,0 +1,16 @@
+package edu.uci.ics.hyracks.dataflow.std.structures;
+
+public interface ISerializableTable {
+
+    public void insert(int entry, TuplePointer tuplePointer);
+
+    public void getTuplePointer(int entry, int offset, TuplePointer tuplePointer);
+
+    public int getFrameCount();
+
+    public int getTupleCount();
+
+    public void reset();
+
+    public void close();
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/structures/SerializableHashTable.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/structures/SerializableHashTable.java
new file mode 100644
index 0000000..9e8cf00
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/structures/SerializableHashTable.java
@@ -0,0 +1,267 @@
+package edu.uci.ics.hyracks.dataflow.std.structures;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+
+/**
+ * An entry in the table is: #elements, #no-empty elements; fIndex, tIndex;
+ * fIndex, tIndex; .... <fIndex, tIndex> forms a tuple pointer
+ */
+public class SerializableHashTable implements ISerializableTable {
+
+    private static final int INT_SIZE = 4;
+    private static final int INIT_ENTRY_SIZE = 4;
+
+    private IntSerDeBuffer[] headers;
+    private List<IntSerDeBuffer> contents = new ArrayList<IntSerDeBuffer>();
+    private List<Integer> frameCurrentIndex = new ArrayList<Integer>();
+    private final IHyracksStageletContext ctx;
+    private int frameCapacity = 0;
+    private int currentLargestFrameIndex = 0;
+    private int tupleCount = 0;
+    private int headerFrameCount = 0;
+    private TuplePointer tempTuplePointer = new TuplePointer();
+
+    public SerializableHashTable(int tableSize, final IHyracksStageletContext ctx) {
+        this.ctx = ctx;
+        int frameSize = ctx.getFrameSize();
+
+        int residual = tableSize * INT_SIZE * 2 % frameSize == 0 ? 0 : 1;
+        int headerSize = tableSize * INT_SIZE * 2 / frameSize + residual;
+        headers = new IntSerDeBuffer[headerSize];
+
+        IntSerDeBuffer frame = new IntSerDeBuffer(ctx.allocateFrame().array());
+        contents.add(frame);
+        frameCurrentIndex.add(0);
+        frameCapacity = frame.capacity();
+    }
+
+    @Override
+    public void insert(int entry, TuplePointer pointer) {
+        int hFrameIndex = getHeaderFrameIndex(entry);
+        int headerOffset = getHeaderFrameOffset(entry);
+        IntSerDeBuffer header = headers[hFrameIndex];
+        if (header == null) {
+            header = new IntSerDeBuffer(ctx.allocateFrame().array());
+            headers[hFrameIndex] = header;
+            resetFrame(header);
+            headerFrameCount++;
+        }
+        int frameIndex = header.getInt(headerOffset);
+        int offsetIndex = header.getInt(headerOffset + 1);
+        if (frameIndex < 0) {
+            // insert first tuple into the entry
+            insertNewEntry(header, headerOffset, INIT_ENTRY_SIZE, pointer);
+        } else {
+            // insert non-first tuple into the entry
+            insertNonFirstTuple(header, headerOffset, frameIndex, offsetIndex, pointer);
+        }
+        tupleCount++;
+    }
+
+    @Override
+    public void getTuplePointer(int entry, int offset, TuplePointer dataPointer) {
+        int hFrameIndex = getHeaderFrameIndex(entry);
+        int headerOffset = getHeaderFrameOffset(entry);
+        IntSerDeBuffer header = headers[hFrameIndex];
+        if (header == null) {
+            dataPointer.frameIndex = -1;
+            dataPointer.tupleIndex = -1;
+            return;
+        }
+        int frameIndex = header.getInt(headerOffset);
+        int offsetIndex = header.getInt(headerOffset + 1);
+        if (frameIndex < 0) {
+            dataPointer.frameIndex = -1;
+            dataPointer.tupleIndex = -1;
+            return;
+        }
+        IntSerDeBuffer frame = contents.get(frameIndex);
+        int entryUsedItems = frame.getInt(offsetIndex + 1);
+        if (offset > entryUsedItems - 1) {
+            dataPointer.frameIndex = -1;
+            dataPointer.tupleIndex = -1;
+            return;
+        }
+        int startIndex = offsetIndex + 2 + offset * 2;
+        while (startIndex >= frameCapacity) {
+            ++frameIndex;
+            startIndex -= frameCapacity;
+        }
+        frame = contents.get(frameIndex);
+        dataPointer.frameIndex = frame.getInt(startIndex);
+        dataPointer.tupleIndex = frame.getInt(startIndex + 1);
+    }
+
+    @Override
+    public void reset() {
+        for (IntSerDeBuffer frame : headers)
+            if (frame != null)
+                resetFrame(frame);
+
+        frameCurrentIndex.clear();
+        for (int i = 0; i < contents.size(); i++) {
+            frameCurrentIndex.add(0);
+        }
+
+        currentLargestFrameIndex = 0;
+        tupleCount = 0;
+    }
+
+    @Override
+    public int getFrameCount() {
+        return headerFrameCount + contents.size();
+    }
+
+    public int getTupleCount() {
+        return tupleCount;
+    }
+
+    @Override
+    public void close() {
+        for (int i = 0; i < headers.length; i++)
+            headers[i] = null;
+        contents.clear();
+        frameCurrentIndex.clear();
+        tupleCount = 0;
+        currentLargestFrameIndex = 0;
+    }
+
+    private void insertNewEntry(IntSerDeBuffer header, int headerOffset, int entryCapacity, TuplePointer pointer) {
+        IntSerDeBuffer lastFrame = contents.get(currentLargestFrameIndex);
+        int lastIndex = frameCurrentIndex.get(currentLargestFrameIndex);
+        int requiredIntCapacity = entryCapacity * 2;
+        int startFrameIndex = currentLargestFrameIndex;
+
+        if (lastIndex + requiredIntCapacity >= frameCapacity) {
+            IntSerDeBuffer newFrame;
+            startFrameIndex++;
+            do {
+                if (currentLargestFrameIndex >= contents.size() - 1) {
+                    newFrame = new IntSerDeBuffer(ctx.allocateFrame().array());
+                    currentLargestFrameIndex++;
+                    contents.add(newFrame);
+                    frameCurrentIndex.add(0);
+                } else {
+                    currentLargestFrameIndex++;
+                    frameCurrentIndex.set(currentLargestFrameIndex, 0);
+                }
+                requiredIntCapacity -= frameCapacity;
+            } while (requiredIntCapacity > 0);
+            lastIndex = 0;
+            lastFrame = contents.get(startFrameIndex);
+        }
+
+        // set header
+        header.writeInt(headerOffset, startFrameIndex);
+        header.writeInt(headerOffset + 1, lastIndex);
+
+        // set the entry
+        lastFrame.writeInt(lastIndex, entryCapacity - 1);
+        lastFrame.writeInt(lastIndex + 1, 1);
+        lastFrame.writeInt(lastIndex + 2, pointer.frameIndex);
+        lastFrame.writeInt(lastIndex + 3, pointer.tupleIndex);
+        int newLastIndex = lastIndex + entryCapacity * 2;
+        newLastIndex = newLastIndex < frameCapacity ? newLastIndex : frameCapacity - 1;
+        frameCurrentIndex.set(startFrameIndex, newLastIndex);
+
+        requiredIntCapacity = entryCapacity * 2 - (frameCapacity - lastIndex);
+        while (requiredIntCapacity > 0) {
+            startFrameIndex++;
+            requiredIntCapacity -= frameCapacity;
+            newLastIndex = requiredIntCapacity < 0 ? requiredIntCapacity + frameCapacity : frameCapacity - 1;
+            frameCurrentIndex.set(startFrameIndex, newLastIndex);
+        }
+    }
+
+    private void insertNonFirstTuple(IntSerDeBuffer header, int headerOffset, int frameIndex, int offsetIndex,
+            TuplePointer pointer) {
+        IntSerDeBuffer frame = contents.get(frameIndex);
+        int entryItems = frame.getInt(offsetIndex);
+        int entryUsedItems = frame.getInt(offsetIndex + 1);
+
+        if (entryUsedItems < entryItems) {
+            frame.writeInt(offsetIndex + 1, entryUsedItems + 1);
+            int startIndex = offsetIndex + 2 + entryUsedItems * 2;
+            while (startIndex >= frameCapacity) {
+                ++frameIndex;
+                startIndex -= frameCapacity;
+            }
+            frame = contents.get(frameIndex);
+            frame.writeInt(startIndex, pointer.frameIndex);
+            frame.writeInt(startIndex + 1, pointer.tupleIndex);
+        } else {
+            int capacity = (entryItems + 1) * 2;
+            header.writeInt(headerOffset, -1);
+            header.writeInt(headerOffset + 1, -1);
+            int fIndex = frame.getInt(offsetIndex + 2);
+            int tIndex = frame.getInt(offsetIndex + 3);
+            tempTuplePointer.frameIndex = fIndex;
+            tempTuplePointer.tupleIndex = tIndex;
+            this.insertNewEntry(header, headerOffset, capacity, tempTuplePointer);
+            int newFrameIndex = header.getInt(headerOffset);
+            int newTupleIndex = header.getInt(headerOffset + 1);
+
+            for (int i = 1; i < entryUsedItems; i++) {
+                int startIndex = offsetIndex + 2 + i * 2;
+                int startFrameIndex = frameIndex;
+                while (startIndex >= frameCapacity) {
+                    ++startFrameIndex;
+                    startIndex -= frameCapacity;
+                }
+                frame = contents.get(startFrameIndex);
+                fIndex = frame.getInt(startIndex);
+                tIndex = frame.getInt(startIndex + 1);
+                tempTuplePointer.frameIndex = fIndex;
+                tempTuplePointer.tupleIndex = tIndex;
+                insertNonFirstTuple(header, headerOffset, newFrameIndex, newTupleIndex, tempTuplePointer);
+            }
+            insertNonFirstTuple(header, headerOffset, newFrameIndex, newTupleIndex, pointer);
+        }
+    }
+
+    private void resetFrame(IntSerDeBuffer frame) {
+        for (int i = 0; i < frameCapacity; i++)
+            frame.writeInt(i, -1);
+    }
+
+    private int getHeaderFrameIndex(int entry) {
+        int frameIndex = entry * 2 / frameCapacity;
+        return frameIndex;
+    }
+
+    private int getHeaderFrameOffset(int entry) {
+        int offset = entry * 2 % frameCapacity;
+        return offset;
+    }
+
+}
+
+class IntSerDeBuffer {
+
+    private byte[] bytes;
+
+    public IntSerDeBuffer(byte[] data) {
+        this.bytes = data;
+    }
+
+    public int getInt(int pos) {
+        int offset = pos * 4;
+        return ((bytes[offset] & 0xff) << 24) + ((bytes[offset + 1] & 0xff) << 16) + ((bytes[offset + 2] & 0xff) << 8)
+                + ((bytes[offset + 3] & 0xff) << 0);
+    }
+
+    public void writeInt(int pos, int value) {
+        int offset = pos * 4;
+        bytes[offset++] = (byte) (value >> 24);
+        bytes[offset++] = (byte) (value >> 16);
+        bytes[offset++] = (byte) (value >> 8);
+        bytes[offset++] = (byte) (value);
+    }
+
+    public int capacity() {
+        return bytes.length / 4;
+    }
+}
diff --git a/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/structures/TuplePointer.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/structures/TuplePointer.java
new file mode 100644
index 0000000..6618fb1
--- /dev/null
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/structures/TuplePointer.java
@@ -0,0 +1,6 @@
+package edu.uci.ics.hyracks.dataflow.std.structures;
+
+public class TuplePointer {
+    public int frameIndex;
+    public int tupleIndex;
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrameFactory.java b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/util/StringSerializationUtils.java
similarity index 64%
copy from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrameFactory.java
copy to hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/util/StringSerializationUtils.java
index 2912cf9..1126c1f 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrameFactory.java
+++ b/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/util/StringSerializationUtils.java
@@ -12,9 +12,16 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+package edu.uci.ics.hyracks.dataflow.std.util;
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+import java.util.Arrays;
 
-public interface IBTreeMetaDataFrameFactory {
-    public IBTreeMetaDataFrame getFrame();
+public class StringSerializationUtils {
+    public static String toString(Object object) {
+        if (object instanceof Object[]) {
+            return Arrays.deepToString((Object[]) object);
+        } else {
+            return String.valueOf(object);
+        }
+    }
 }
\ No newline at end of file
diff --git a/hyracks-documentation/.classpath b/hyracks-documentation/.classpath
index 3f62785..d0bec0f 100644
--- a/hyracks-documentation/.classpath
+++ b/hyracks-documentation/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.4"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.5"/>
 	<classpathentry kind="con" path="org.maven.ide.eclipse.MAVEN2_CLASSPATH_CONTAINER"/>
 	<classpathentry kind="output" path="target/classes"/>
 </classpath>
diff --git a/hyracks-documentation/.settings/org.eclipse.jdt.core.prefs b/hyracks-documentation/.settings/org.eclipse.jdt.core.prefs
index 15a7e04..75a3d16 100644
--- a/hyracks-documentation/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-documentation/.settings/org.eclipse.jdt.core.prefs
@@ -1,6 +1,6 @@
-#Tue Oct 19 13:07:01 PDT 2010
+#Thu Aug 04 11:50:30 PDT 2011
 eclipse.preferences.version=1
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.4
-org.eclipse.jdt.core.compiler.compliance=1.4
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.5
+org.eclipse.jdt.core.compiler.compliance=1.5
 org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
-org.eclipse.jdt.core.compiler.source=1.4
+org.eclipse.jdt.core.compiler.source=1.5
diff --git a/hyracks-examples/btree-example/btreeapp/.classpath b/hyracks-examples/btree-example/btreeapp/.classpath
index 3f62785..d0bec0f 100644
--- a/hyracks-examples/btree-example/btreeapp/.classpath
+++ b/hyracks-examples/btree-example/btreeapp/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.4"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.5"/>
 	<classpathentry kind="con" path="org.maven.ide.eclipse.MAVEN2_CLASSPATH_CONTAINER"/>
 	<classpathentry kind="output" path="target/classes"/>
 </classpath>
diff --git a/hyracks-examples/btree-example/btreeapp/.settings/org.eclipse.jdt.core.prefs b/hyracks-examples/btree-example/btreeapp/.settings/org.eclipse.jdt.core.prefs
index fdf1b32..75a3d16 100644
--- a/hyracks-examples/btree-example/btreeapp/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-examples/btree-example/btreeapp/.settings/org.eclipse.jdt.core.prefs
@@ -1,6 +1,6 @@
-#Wed Oct 06 08:06:49 PDT 2010
+#Thu Aug 04 11:50:30 PDT 2011
 eclipse.preferences.version=1
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.4
-org.eclipse.jdt.core.compiler.compliance=1.4
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.5
+org.eclipse.jdt.core.compiler.compliance=1.5
 org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
-org.eclipse.jdt.core.compiler.source=1.4
+org.eclipse.jdt.core.compiler.source=1.5
diff --git a/hyracks-examples/btree-example/btreeclient/.settings/org.eclipse.jdt.core.prefs b/hyracks-examples/btree-example/btreeclient/.settings/org.eclipse.jdt.core.prefs
index 7b596e8..7cf8ad6 100644
--- a/hyracks-examples/btree-example/btreeclient/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-examples/btree-example/btreeclient/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Mon Dec 20 19:05:17 PST 2010
+#Fri May 20 19:34:07 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/InsertPipelineExample.java b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/InsertPipelineExample.java
index b5468ad..7aeaf77 100644
--- a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/InsertPipelineExample.java
+++ b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/InsertPipelineExample.java
@@ -41,17 +41,19 @@
 import edu.uci.ics.hyracks.dataflow.std.connectors.OneToOneConnectorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
 import edu.uci.ics.hyracks.dataflow.std.misc.NullSinkOperatorDescriptor;
-import edu.uci.ics.hyracks.examples.btree.helper.BTreeRegistryProvider;
 import edu.uci.ics.hyracks.examples.btree.helper.DataGenOperatorDescriptor;
 import edu.uci.ics.hyracks.examples.btree.helper.StorageManagerInterface;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeInsertUpdateDeleteOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.IBTreeRegistryProvider;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.examples.btree.helper.TreeIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexInsertUpdateDeleteOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
 // This example will insert tuples into the primary and secondary index using an insert pipeline
@@ -127,7 +129,7 @@
         // run data generator on first nodecontroller given
         PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, dataGen, splitNCs[0]);
 
-        IBTreeRegistryProvider btreeRegistryProvider = BTreeRegistryProvider.INSTANCE;
+        IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider = TreeIndexRegistryProvider.INSTANCE;
         IStorageManagerInterface storageManager = StorageManagerInterface.INSTANCE;
 
         // prepare insertion into primary index
@@ -141,8 +143,8 @@
 
         // create factories and providers for secondary B-Tree
         TypeAwareTupleWriterFactory primaryTupleWriterFactory = new TypeAwareTupleWriterFactory(primaryTypeTraits);
-        IBTreeInteriorFrameFactory primaryInteriorFrameFactory = new NSMInteriorFrameFactory(primaryTupleWriterFactory);
-        IBTreeLeafFrameFactory primaryLeafFrameFactory = new NSMLeafFrameFactory(primaryTupleWriterFactory);
+        ITreeIndexFrameFactory primaryInteriorFrameFactory = new BTreeNSMInteriorFrameFactory(primaryTupleWriterFactory);
+        ITreeIndexFrameFactory primaryLeafFrameFactory = new BTreeNSMLeafFrameFactory(primaryTupleWriterFactory);
 
         // the B-Tree expects its keyfields to be at the front of its input
         // tuple
@@ -154,11 +156,13 @@
         primaryComparatorFactories[0] = IntegerBinaryComparatorFactory.INSTANCE;
         IFileSplitProvider primarySplitProvider = JobHelper.createFileSplitProvider(splitNCs, options.primaryBTreeName);
 
+        ITreeIndexOpHelperFactory opHelperFactory = new BTreeOpHelperFactory();
+        
         // create operator descriptor
-        BTreeInsertUpdateDeleteOperatorDescriptor primaryInsert = new BTreeInsertUpdateDeleteOperatorDescriptor(spec,
-                recDesc, storageManager, btreeRegistryProvider, primarySplitProvider, primaryInteriorFrameFactory,
+        TreeIndexInsertUpdateDeleteOperatorDescriptor primaryInsert = new TreeIndexInsertUpdateDeleteOperatorDescriptor(spec,
+                recDesc, storageManager, treeIndexRegistryProvider, primarySplitProvider, primaryInteriorFrameFactory,
                 primaryLeafFrameFactory, primaryTypeTraits, primaryComparatorFactories, primaryFieldPermutation,
-                BTreeOp.BTO_INSERT);
+                IndexOp.INSERT, opHelperFactory);
         JobHelper.createPartitionConstraint(spec, primaryInsert, splitNCs);
 
         // prepare insertion into secondary index
@@ -170,9 +174,9 @@
 
         // create factories and providers for secondary B-Tree
         TypeAwareTupleWriterFactory secondaryTupleWriterFactory = new TypeAwareTupleWriterFactory(secondaryTypeTraits);
-        IBTreeInteriorFrameFactory secondaryInteriorFrameFactory = new NSMInteriorFrameFactory(
+        ITreeIndexFrameFactory secondaryInteriorFrameFactory = new BTreeNSMInteriorFrameFactory(
                 secondaryTupleWriterFactory);
-        IBTreeLeafFrameFactory secondaryLeafFrameFactory = new NSMLeafFrameFactory(secondaryTupleWriterFactory);
+        ITreeIndexFrameFactory secondaryLeafFrameFactory = new BTreeNSMLeafFrameFactory(secondaryTupleWriterFactory);
 
         // the B-Tree expects its keyfields to be at the front of its input
         // tuple
@@ -184,10 +188,10 @@
         IFileSplitProvider secondarySplitProvider = JobHelper.createFileSplitProvider(splitNCs,
                 options.secondaryBTreeName);
         // create operator descriptor
-        BTreeInsertUpdateDeleteOperatorDescriptor secondaryInsert = new BTreeInsertUpdateDeleteOperatorDescriptor(spec,
-                recDesc, storageManager, btreeRegistryProvider, secondarySplitProvider, secondaryInteriorFrameFactory,
+        TreeIndexInsertUpdateDeleteOperatorDescriptor secondaryInsert = new TreeIndexInsertUpdateDeleteOperatorDescriptor(spec,
+                recDesc, storageManager, treeIndexRegistryProvider, secondarySplitProvider, secondaryInteriorFrameFactory,
                 secondaryLeafFrameFactory, secondaryTypeTraits, secondaryComparatorFactories,
-                secondaryFieldPermutation, BTreeOp.BTO_INSERT);
+                secondaryFieldPermutation, IndexOp.INSERT, opHelperFactory);
         JobHelper.createPartitionConstraint(spec, secondaryInsert, splitNCs);
 
         // end the insert pipeline at this sink operator
diff --git a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexBulkLoadExample.java b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexBulkLoadExample.java
index 204bdf5..1533714 100644
--- a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexBulkLoadExample.java
+++ b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexBulkLoadExample.java
@@ -39,16 +39,18 @@
 import edu.uci.ics.hyracks.dataflow.std.connectors.OneToOneConnectorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
 import edu.uci.ics.hyracks.dataflow.std.sort.ExternalSortOperatorDescriptor;
-import edu.uci.ics.hyracks.examples.btree.helper.BTreeRegistryProvider;
 import edu.uci.ics.hyracks.examples.btree.helper.DataGenOperatorDescriptor;
 import edu.uci.ics.hyracks.examples.btree.helper.StorageManagerInterface;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeBulkLoadOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.IBTreeRegistryProvider;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.examples.btree.helper.TreeIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexBulkLoadOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
 // This example will load a primary index from randomly generated data
@@ -144,20 +146,21 @@
 
         // create factories and providers for B-Tree
         TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
-        IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(tupleWriterFactory);
-        IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(tupleWriterFactory);
-        IBTreeRegistryProvider btreeRegistryProvider = BTreeRegistryProvider.INSTANCE;
+        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
+        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
+        IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider = TreeIndexRegistryProvider.INSTANCE;
         IStorageManagerInterface storageManager = StorageManagerInterface.INSTANCE;
 
         // the B-Tree expects its keyfields to be at the front of its input
         // tuple
         int[] fieldPermutation = { 2, 1, 3, 4 }; // map field 2 of input tuple
                                                  // to field 0 of B-Tree tuple,
-                                                 // etc.
+                                                 // etc.                
         IFileSplitProvider btreeSplitProvider = JobHelper.createFileSplitProvider(splitNCs, options.btreeName);
-        BTreeBulkLoadOperatorDescriptor btreeBulkLoad = new BTreeBulkLoadOperatorDescriptor(spec, storageManager,
-                btreeRegistryProvider, btreeSplitProvider, interiorFrameFactory, leafFrameFactory, typeTraits,
-                comparatorFactories, fieldPermutation, 0.7f);
+        ITreeIndexOpHelperFactory opHelperFactory = new BTreeOpHelperFactory();
+        TreeIndexBulkLoadOperatorDescriptor btreeBulkLoad = new TreeIndexBulkLoadOperatorDescriptor(spec, storageManager,
+                treeIndexRegistryProvider, btreeSplitProvider, interiorFrameFactory, leafFrameFactory, typeTraits,
+                comparatorFactories, fieldPermutation, 0.7f, opHelperFactory);
         JobHelper.createPartitionConstraint(spec, btreeBulkLoad, splitNCs);
 
         // distribute the records from the datagen via hashing to the bulk load
diff --git a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexEnlistFilesExample.java b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexEnlistFilesExample.java
index a7ee0dc..c991a89 100644
--- a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexEnlistFilesExample.java
+++ b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexEnlistFilesExample.java
@@ -31,15 +31,17 @@
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.examples.btree.helper.BTreeRegistryProvider;
 import edu.uci.ics.hyracks.examples.btree.helper.StorageManagerInterface;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeFileEnlistmentOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.IBTreeRegistryProvider;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.examples.btree.helper.TreeIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexFileEnlistmentOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
 // This example will enlist existing files as primary index
@@ -99,18 +101,19 @@
 
         // create factories and providers for B-Tree
         TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
-        IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(tupleWriterFactory);
-        IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(tupleWriterFactory);
-        IBTreeRegistryProvider btreeRegistryProvider = BTreeRegistryProvider.INSTANCE;
+        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
+        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
+        IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider = TreeIndexRegistryProvider.INSTANCE;
         IStorageManagerInterface storageManager = StorageManagerInterface.INSTANCE;
 
         IBinaryComparatorFactory[] comparatorFactories = new IBinaryComparatorFactory[1];
         comparatorFactories[0] = IntegerBinaryComparatorFactory.INSTANCE;
 
         IFileSplitProvider btreeSplitProvider = JobHelper.createFileSplitProvider(splitNCs, options.btreeName);
-        BTreeFileEnlistmentOperatorDescriptor fileEnlistmentOp = new BTreeFileEnlistmentOperatorDescriptor(spec,
-                recDesc, storageManager, btreeRegistryProvider, btreeSplitProvider, interiorFrameFactory,
-                leafFrameFactory, typeTraits, comparatorFactories);
+        ITreeIndexOpHelperFactory opHelperFactory = new BTreeOpHelperFactory();
+        TreeIndexFileEnlistmentOperatorDescriptor fileEnlistmentOp = new TreeIndexFileEnlistmentOperatorDescriptor(spec,
+                recDesc, storageManager, treeIndexRegistryProvider, btreeSplitProvider, interiorFrameFactory,
+                leafFrameFactory, typeTraits, comparatorFactories, opHelperFactory);
         JobHelper.createPartitionConstraint(spec, fileEnlistmentOp, splitNCs);
 
         spec.addRoot(fileEnlistmentOp);
diff --git a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexSearchExample.java b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexSearchExample.java
index b43efd2..7e4ae9d 100644
--- a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexSearchExample.java
+++ b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/PrimaryIndexSearchExample.java
@@ -37,15 +37,17 @@
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
 import edu.uci.ics.hyracks.dataflow.std.misc.ConstantTupleSourceOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.misc.PrinterOperatorDescriptor;
-import edu.uci.ics.hyracks.examples.btree.helper.BTreeRegistryProvider;
 import edu.uci.ics.hyracks.examples.btree.helper.StorageManagerInterface;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
+import edu.uci.ics.hyracks.examples.btree.helper.TreeIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeOpHelperFactory;
 import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeSearchOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.IBTreeRegistryProvider;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
 // This example will perform an ordered scan on the primary index
@@ -101,9 +103,9 @@
 
         // create factories and providers for B-Tree
         TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
-        IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(tupleWriterFactory);
-        IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(tupleWriterFactory);
-        IBTreeRegistryProvider btreeRegistryProvider = BTreeRegistryProvider.INSTANCE;
+        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
+        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
+        IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider = TreeIndexRegistryProvider.INSTANCE;
         IStorageManagerInterface storageManager = StorageManagerInterface.INSTANCE;
 
         // schema of tuples coming out of primary index
@@ -144,9 +146,10 @@
                                      // into search op
 
         IFileSplitProvider btreeSplitProvider = JobHelper.createFileSplitProvider(splitNCs, options.btreeName);
+        ITreeIndexOpHelperFactory opHelperFactory = new BTreeOpHelperFactory();
         BTreeSearchOperatorDescriptor btreeSearchOp = new BTreeSearchOperatorDescriptor(spec, recDesc, storageManager,
-                btreeRegistryProvider, btreeSplitProvider, interiorFrameFactory, leafFrameFactory, typeTraits,
-                comparatorFactories, true, lowKeyFields, highKeyFields, true, true);
+                treeIndexRegistryProvider, btreeSplitProvider, interiorFrameFactory, leafFrameFactory, typeTraits,
+                comparatorFactories, true, lowKeyFields, highKeyFields, true, true, opHelperFactory);
         JobHelper.createPartitionConstraint(spec, btreeSearchOp, splitNCs);
 
         // have each node print the results of its respective B-Tree
diff --git a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/SecondaryIndexBulkLoadExample.java b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/SecondaryIndexBulkLoadExample.java
index 4940c2a..b061811 100644
--- a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/SecondaryIndexBulkLoadExample.java
+++ b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/SecondaryIndexBulkLoadExample.java
@@ -34,16 +34,18 @@
 import edu.uci.ics.hyracks.dataflow.std.connectors.OneToOneConnectorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
 import edu.uci.ics.hyracks.dataflow.std.sort.ExternalSortOperatorDescriptor;
-import edu.uci.ics.hyracks.examples.btree.helper.BTreeRegistryProvider;
 import edu.uci.ics.hyracks.examples.btree.helper.StorageManagerInterface;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeBulkLoadOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeDiskOrderScanOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.IBTreeRegistryProvider;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.examples.btree.helper.TreeIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexBulkLoadOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexDiskOrderScanOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
 // This example will load a secondary index with <key, primary-index key> pairs
@@ -95,8 +97,8 @@
         JobSpecification spec = new JobSpecification();
 
         String[] splitNCs = options.ncs.split(",");
-
-        IBTreeRegistryProvider btreeRegistryProvider = BTreeRegistryProvider.INSTANCE;
+        
+        IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider = TreeIndexRegistryProvider.INSTANCE;
         IStorageManagerInterface storageManager = StorageManagerInterface.INSTANCE;
 
         // schema of tuples that we are retrieving from the primary index
@@ -118,14 +120,15 @@
 
         // create factories and providers for primary B-Tree
         TypeAwareTupleWriterFactory primaryTupleWriterFactory = new TypeAwareTupleWriterFactory(primaryTypeTraits);
-        IBTreeInteriorFrameFactory primaryInteriorFrameFactory = new NSMInteriorFrameFactory(primaryTupleWriterFactory);
-        IBTreeLeafFrameFactory primaryLeafFrameFactory = new NSMLeafFrameFactory(primaryTupleWriterFactory);
+        ITreeIndexFrameFactory primaryInteriorFrameFactory = new BTreeNSMInteriorFrameFactory(primaryTupleWriterFactory);
+        ITreeIndexFrameFactory primaryLeafFrameFactory = new BTreeNSMLeafFrameFactory(primaryTupleWriterFactory);
 
         // use a disk-order scan to read primary index
         IFileSplitProvider primarySplitProvider = JobHelper.createFileSplitProvider(splitNCs, options.primaryBTreeName);
-        BTreeDiskOrderScanOperatorDescriptor btreeScanOp = new BTreeDiskOrderScanOperatorDescriptor(spec, recDesc,
-                storageManager, btreeRegistryProvider, primarySplitProvider, primaryInteriorFrameFactory,
-                primaryLeafFrameFactory, primaryTypeTraits);
+        ITreeIndexOpHelperFactory opHelperFactory = new BTreeOpHelperFactory();
+        TreeIndexDiskOrderScanOperatorDescriptor btreeScanOp = new TreeIndexDiskOrderScanOperatorDescriptor(spec, recDesc,
+                storageManager, treeIndexRegistryProvider, primarySplitProvider, primaryInteriorFrameFactory,
+                primaryLeafFrameFactory, primaryTypeTraits, opHelperFactory);
         JobHelper.createPartitionConstraint(spec, btreeScanOp, splitNCs);
 
         // sort the tuples as preparation for bulk load into secondary index
@@ -147,17 +150,17 @@
 
         // create factories and providers for secondary B-Tree
         TypeAwareTupleWriterFactory secondaryTupleWriterFactory = new TypeAwareTupleWriterFactory(secondaryTypeTraits);
-        IBTreeInteriorFrameFactory secondaryInteriorFrameFactory = new NSMInteriorFrameFactory(
+        ITreeIndexFrameFactory secondaryInteriorFrameFactory = new BTreeNSMInteriorFrameFactory(
                 secondaryTupleWriterFactory);
-        IBTreeLeafFrameFactory secondaryLeafFrameFactory = new NSMLeafFrameFactory(secondaryTupleWriterFactory);
+        ITreeIndexFrameFactory secondaryLeafFrameFactory = new BTreeNSMLeafFrameFactory(secondaryTupleWriterFactory);
 
         // the B-Tree expects its keyfields to be at the front of its input
         // tuple
         int[] fieldPermutation = { 1, 0 };
         IFileSplitProvider btreeSplitProvider = JobHelper.createFileSplitProvider(splitNCs, options.secondaryBTreeName);
-        BTreeBulkLoadOperatorDescriptor btreeBulkLoad = new BTreeBulkLoadOperatorDescriptor(spec, storageManager,
-                btreeRegistryProvider, btreeSplitProvider, secondaryInteriorFrameFactory, secondaryLeafFrameFactory,
-                secondaryTypeTraits, comparatorFactories, fieldPermutation, 0.7f);
+        TreeIndexBulkLoadOperatorDescriptor btreeBulkLoad = new TreeIndexBulkLoadOperatorDescriptor(spec, storageManager,
+                treeIndexRegistryProvider, btreeSplitProvider, secondaryInteriorFrameFactory, secondaryLeafFrameFactory,
+                secondaryTypeTraits, comparatorFactories, fieldPermutation, 0.7f, opHelperFactory);
         JobHelper.createPartitionConstraint(spec, btreeBulkLoad, splitNCs);
 
         // connect the ops
diff --git a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/SecondaryIndexSearchExample.java b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/SecondaryIndexSearchExample.java
index a770f09..5e5eaeb 100644
--- a/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/SecondaryIndexSearchExample.java
+++ b/hyracks-examples/btree-example/btreeclient/src/main/java/edu/uci/ics/hyracks/examples/btree/client/SecondaryIndexSearchExample.java
@@ -37,15 +37,17 @@
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
 import edu.uci.ics.hyracks.dataflow.std.misc.ConstantTupleSourceOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.misc.PrinterOperatorDescriptor;
-import edu.uci.ics.hyracks.examples.btree.helper.BTreeRegistryProvider;
 import edu.uci.ics.hyracks.examples.btree.helper.StorageManagerInterface;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
+import edu.uci.ics.hyracks.examples.btree.helper.TreeIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeOpHelperFactory;
 import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeSearchOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.IBTreeRegistryProvider;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
 // This example will perform range search on the secondary index
@@ -95,7 +97,7 @@
 
         String[] splitNCs = options.ncs.split(",");
 
-        IBTreeRegistryProvider btreeRegistryProvider = BTreeRegistryProvider.INSTANCE;
+        IIndexRegistryProvider<ITreeIndex> btreeRegistryProvider = TreeIndexRegistryProvider.INSTANCE;
         IStorageManagerInterface storageManager = StorageManagerInterface.INSTANCE;
 
         // schema of tuples coming out of secondary index
@@ -109,9 +111,9 @@
 
         // create factories and providers for secondary B-Tree
         TypeAwareTupleWriterFactory secondaryTupleWriterFactory = new TypeAwareTupleWriterFactory(secondaryTypeTraits);
-        IBTreeInteriorFrameFactory secondaryInteriorFrameFactory = new NSMInteriorFrameFactory(
+        ITreeIndexFrameFactory secondaryInteriorFrameFactory = new BTreeNSMInteriorFrameFactory(
                 secondaryTupleWriterFactory);
-        IBTreeLeafFrameFactory secondaryLeafFrameFactory = new NSMLeafFrameFactory(secondaryTupleWriterFactory);
+        ITreeIndexFrameFactory secondaryLeafFrameFactory = new BTreeNSMLeafFrameFactory(secondaryTupleWriterFactory);
 
         // schema of tuples coming out of primary index
         RecordDescriptor primaryRecDesc = new RecordDescriptor(new ISerializerDeserializer[] {
@@ -127,8 +129,8 @@
 
         // create factories and providers for secondary B-Tree
         TypeAwareTupleWriterFactory primaryTupleWriterFactory = new TypeAwareTupleWriterFactory(primaryTypeTraits);
-        IBTreeInteriorFrameFactory primaryInteriorFrameFactory = new NSMInteriorFrameFactory(primaryTupleWriterFactory);
-        IBTreeLeafFrameFactory primaryLeafFrameFactory = new NSMLeafFrameFactory(primaryTupleWriterFactory);
+        ITreeIndexFrameFactory primaryInteriorFrameFactory = new BTreeNSMInteriorFrameFactory(primaryTupleWriterFactory);
+        ITreeIndexFrameFactory primaryLeafFrameFactory = new BTreeNSMLeafFrameFactory(primaryTupleWriterFactory);
 
         // comparators for btree, note that we only need a comparator for the
         // non-unique key
@@ -169,10 +171,11 @@
 
         IFileSplitProvider secondarySplitProvider = JobHelper.createFileSplitProvider(splitNCs,
                 options.secondaryBTreeName);
+        ITreeIndexOpHelperFactory opHelperFactory = new BTreeOpHelperFactory();
         BTreeSearchOperatorDescriptor secondarySearchOp = new BTreeSearchOperatorDescriptor(spec, secondaryRecDesc,
                 storageManager, btreeRegistryProvider, secondarySplitProvider, secondaryInteriorFrameFactory,
                 secondaryLeafFrameFactory, secondaryTypeTraits, comparatorFactories, true, secondaryLowKeyFields,
-                secondaryHighKeyFields, true, true);
+                secondaryHighKeyFields, true, true, opHelperFactory);
         JobHelper.createPartitionConstraint(spec, secondarySearchOp, splitNCs);
 
         // secondary index will output tuples with [UTF8String, Integer]
@@ -188,7 +191,7 @@
         BTreeSearchOperatorDescriptor primarySearchOp = new BTreeSearchOperatorDescriptor(spec, primaryRecDesc,
                 storageManager, btreeRegistryProvider, primarySplitProvider, primaryInteriorFrameFactory,
                 primaryLeafFrameFactory, primaryTypeTraits, comparatorFactories, true, primaryLowKeyFields,
-                primaryHighKeyFields, true, true);
+                primaryHighKeyFields, true, true, opHelperFactory);
         JobHelper.createPartitionConstraint(spec, primarySearchOp, splitNCs);
 
         // have each node print the results of its respective B-Tree
diff --git a/hyracks-examples/btree-example/btreehelper/.settings/org.eclipse.jdt.core.prefs b/hyracks-examples/btree-example/btreehelper/.settings/org.eclipse.jdt.core.prefs
index 367ddc4..dfac000 100644
--- a/hyracks-examples/btree-example/btreehelper/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-examples/btree-example/btreehelper/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Wed Oct 06 08:06:49 PDT 2010
+#Fri May 20 19:34:05 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/BTreeRegistryProvider.java b/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/BTreeRegistryProvider.java
deleted file mode 100644
index 57b10a3..0000000
--- a/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/BTreeRegistryProvider.java
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.examples.btree.helper;
-
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeRegistry;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.IBTreeRegistryProvider;
-
-public class BTreeRegistryProvider implements IBTreeRegistryProvider {
-    private static final long serialVersionUID = 1L;
-
-    public static final BTreeRegistryProvider INSTANCE = new BTreeRegistryProvider();
-
-    private BTreeRegistryProvider() {
-    }
-
-    @Override
-    public BTreeRegistry getBTreeRegistry(IHyracksStageletContext ctx) {
-        return RuntimeContext.get(ctx).getBTreeRegistry();
-    }
-}
\ No newline at end of file
diff --git a/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/RuntimeContext.java b/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/RuntimeContext.java
index 9f99468..9fd7df4 100644
--- a/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/RuntimeContext.java
+++ b/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/RuntimeContext.java
@@ -17,7 +17,8 @@
 
 import edu.uci.ics.hyracks.api.application.INCApplicationContext;
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeRegistry;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexRegistry;
 import edu.uci.ics.hyracks.storage.common.buffercache.BufferCache;
 import edu.uci.ics.hyracks.storage.common.buffercache.ClockPageReplacementStrategy;
 import edu.uci.ics.hyracks.storage.common.buffercache.HeapBufferAllocator;
@@ -29,7 +30,7 @@
 import edu.uci.ics.hyracks.storage.common.smi.TransientFileMapManager;
 
 public class RuntimeContext {
-    private BTreeRegistry btreeRegistry;
+    private IndexRegistry<ITreeIndex> treeIndexRegistry;
     private IBufferCache bufferCache;
     private IFileMapManager fileMapManager;
 
@@ -37,8 +38,8 @@
         fileMapManager = new TransientFileMapManager();
         ICacheMemoryAllocator allocator = new HeapBufferAllocator();
         IPageReplacementStrategy prs = new ClockPageReplacementStrategy();
-        bufferCache = new BufferCache(appCtx.getRootContext().getIOManager(), allocator, prs, fileMapManager, 32768, 50);
-        btreeRegistry = new BTreeRegistry();
+        bufferCache = new BufferCache(appCtx.getRootContext().getIOManager(), allocator, prs, fileMapManager, 32768, 50, 100);
+        treeIndexRegistry = new IndexRegistry<ITreeIndex>();
     }
 
     public void close() {
@@ -53,8 +54,8 @@
         return fileMapManager;
     }
 
-    public BTreeRegistry getBTreeRegistry() {
-        return btreeRegistry;
+    public IndexRegistry<ITreeIndex> getTreeIndexRegistry() {
+        return treeIndexRegistry;
     }
     
     public static RuntimeContext get(IHyracksStageletContext ctx) {
diff --git a/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/TreeIndexRegistryProvider.java b/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/TreeIndexRegistryProvider.java
new file mode 100644
index 0000000..6a6ddf8
--- /dev/null
+++ b/hyracks-examples/btree-example/btreehelper/src/main/java/edu/uci/ics/hyracks/examples/btree/helper/TreeIndexRegistryProvider.java
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.examples.btree.helper;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexRegistry;
+
+public class TreeIndexRegistryProvider implements IIndexRegistryProvider<ITreeIndex> {
+    private static final long serialVersionUID = 1L;
+
+    public static final TreeIndexRegistryProvider INSTANCE = new TreeIndexRegistryProvider();
+
+    private TreeIndexRegistryProvider() {
+    }
+
+    @Override
+    public IndexRegistry<ITreeIndex> getRegistry(IHyracksStageletContext ctx) {
+        return RuntimeContext.get(ctx).getTreeIndexRegistry();
+    }
+}
\ No newline at end of file
diff --git a/hyracks-examples/hyracks-integration-tests/.settings/org.eclipse.jdt.core.prefs b/hyracks-examples/hyracks-integration-tests/.settings/org.eclipse.jdt.core.prefs
index e5faa3a..a80ec7b 100644
--- a/hyracks-examples/hyracks-integration-tests/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-examples/hyracks-integration-tests/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Thu Jul 29 15:30:35 PDT 2010
+#Fri May 20 19:34:08 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-examples/hyracks-integration-tests/data/orders-with-locations.txt b/hyracks-examples/hyracks-integration-tests/data/orders-with-locations.txt
new file mode 100644
index 0000000..f936a6e
--- /dev/null
+++ b/hyracks-examples/hyracks-integration-tests/data/orders-with-locations.txt
@@ -0,0 +1,750 @@
+1|37|O|131251.81|1996-01-02|5-LOW|Clerk#000000951|0|nstructions sleep furiously among |42.3631|-71.065|42.3631|-71.065|
+2|79|O|40183.29|1996-12-01|1-URGENT|Clerk#000000880|0| foxes. pending accounts at the pending, silent asymptot|42.1091|-70.696|42.1091|-70.696|
+3|124|F|160882.76|1993-10-14|5-LOW|Clerk#000000955|0|sly final accounts boost. carefully regular ideas cajole carefully. depos|40.8151|-73.0452|40.8151|-73.0452|
+4|137|O|31084.79|1995-10-11|5-LOW|Clerk#000000124|0|sits. slyly regular warthogs cajole. regular, regular theodolites acro|40.8151|-73.0452|40.8151|-73.0452|
+5|46|F|86615.25|1994-07-30|5-LOW|Clerk#000000925|0|quickly. bold deposits sleep slyly. packages use slyly|42.2481|-71.174|42.2481|-71.174|
+6|56|F|36468.55|1992-02-21|4-NOT SPECIFIED|Clerk#000000058|0|ggle. special, final requests are against the furiously specia|61.1201|-149.89|61.1201|-149.89|
+7|40|O|171488.73|1996-01-10|2-HIGH|Clerk#000000470|0|ly special requests |61.1501|-149.926|61.1501|-149.926|
+32|131|O|116923.00|1995-07-16|2-HIGH|Clerk#000000616|0|ise blithely bold, regular requests. quickly unusual dep|61.181|-149.814|61.181|-149.814|
+33|67|F|99798.76|1993-10-27|3-MEDIUM|Clerk#000000409|0|uriously. furiously final request|61.1517|-149.86|61.1517|-149.86|
+34|62|O|41670.02|1998-07-21|3-MEDIUM|Clerk#000000223|0|ly final packages. fluffily final deposits wake blithely ideas. spe|61.1806|-149.814|61.1806|-149.814|
+35|128|O|148789.52|1995-10-23|4-NOT SPECIFIED|Clerk#000000259|0|zzle. carefully enticing deposits nag furio|61.1806|-149.775|61.1806|-149.775|
+36|116|O|38988.98|1995-11-03|1-URGENT|Clerk#000000358|0| quick packages are blithely. slyly silent accounts wake qu|61.1806|-149.775|61.1806|-149.775|
+37|88|F|113701.89|1992-06-03|3-MEDIUM|Clerk#000000456|0|kly regular pinto beans. carefully unusual waters cajole never|61.1806|-149.775|61.1806|-149.775|
+38|125|O|46366.56|1996-08-21|4-NOT SPECIFIED|Clerk#000000604|0|haggle blithely. furiously express ideas haggle blithely furiously regular re|61.2113|-149.824|61.2113|-149.824|
+39|82|O|219707.84|1996-09-20|3-MEDIUM|Clerk#000000659|0|ole express, ironic requests: ir|61.1967|-149.877|61.1967|-149.877|
+64|34|F|20065.73|1994-07-16|3-MEDIUM|Clerk#000000661|0|wake fluffily. sometimes ironic pinto beans about the dolphin|61.2164|-149.892|61.2164|-149.892|
+65|17|P|65883.92|1995-03-18|1-URGENT|Clerk#000000632|0|ular requests are blithely pending orbits-- even requests against the deposit|61.1571|-149.883|61.1571|-149.883|
+66|130|F|79258.24|1994-01-20|5-LOW|Clerk#000000743|0|y pending requests integrate|61.2048|-149.834|61.2048|-149.834|
+67|58|O|116227.05|1996-12-19|4-NOT SPECIFIED|Clerk#000000547|0|symptotes haggle slyly around the furiously iron|61.0956|-149.843|61.0956|-149.843|
+68|29|O|215135.72|1998-04-18|3-MEDIUM|Clerk#000000440|0| pinto beans sleep carefully. blithely ironic deposits haggle furiously acro|61.1491|-149.809|61.1491|-149.809|
+69|85|F|162176.23|1994-06-04|4-NOT SPECIFIED|Clerk#000000330|0| depths atop the slyly thin deposits detect among the furiously silent accou|61.1981|-149.871|61.1981|-149.871|
+70|65|F|84651.80|1993-12-18|5-LOW|Clerk#000000322|0| carefully ironic request|61.1982|-149.876|61.1982|-149.876|
+71|4|O|178821.73|1998-01-24|4-NOT SPECIFIED|Clerk#000000271|0| express deposits along the blithely regul|61.1924|-149.909|61.1924|-149.909|
+96|109|F|55090.67|1994-04-17|2-HIGH|Clerk#000000395|0|oost furiously. pinto|61.2204|-149.728|61.2204|-149.728|
+97|22|F|68908.31|1993-01-29|3-MEDIUM|Clerk#000000547|0|hang blithely along the regular accounts. furiously even ideas after the|61.196|-149.864|61.196|-149.864|
+98|106|F|51004.44|1994-09-25|1-URGENT|Clerk#000000448|0|c asymptotes. quickly regular packages should have to nag re|61.1987|-149.889|61.1987|-149.889|
+99|89|F|92326.79|1994-03-13|4-NOT SPECIFIED|Clerk#000000973|0|e carefully ironic packages. pending|61.1984|-149.897|61.1984|-149.897|
+100|148|O|141311.01|1998-02-28|4-NOT SPECIFIED|Clerk#000000577|0|heodolites detect slyly alongside of the ent|61.1897|-149.898|61.1897|-149.898|
+101|28|O|95591.40|1996-03-17|3-MEDIUM|Clerk#000000419|0|ding accounts above the slyly final asymptote|61.1228|-149.81|61.1228|-149.81|
+102|1|O|113954.89|1997-05-09|2-HIGH|Clerk#000000596|0| slyly according to the asymptotes. carefully final packages integrate furious|61.1649|-149.881|61.1649|-149.881|
+103|31|O|95563.95|1996-06-20|4-NOT SPECIFIED|Clerk#000000090|0|ges. carefully unusual instructions haggle quickly regular f|61.1934|-149.887|61.1934|-149.887|
+128|74|F|36333.34|1992-06-15|1-URGENT|Clerk#000000385|0|ns integrate fluffily. ironic asymptotes after the regular excuses nag around |61.2164|-149.892|61.2164|-149.892|
+129|73|F|188124.55|1992-11-19|5-LOW|Clerk#000000859|0|ing tithes. carefully pending deposits boost about the silently express |61.1932|-149.886|61.1932|-149.886|
+130|37|F|115717.37|1992-05-08|2-HIGH|Clerk#000000036|0|le slyly unusual, regular packages? express deposits det|61.2072|-149.888|61.2072|-149.888|
+131|94|F|96596.81|1994-06-08|3-MEDIUM|Clerk#000000625|0|after the fluffily special foxes integrate s|61.2125|-149.904|61.2125|-149.904|
+132|28|F|118802.62|1993-06-11|3-MEDIUM|Clerk#000000488|0|sits are daringly accounts. carefully regular foxes sleep slyly about the|61.2142|-149.806|61.2142|-149.806|
+133|44|O|80437.72|1997-11-29|1-URGENT|Clerk#000000738|0|usly final asymptotes |61.1866|-149.923|61.1866|-149.923|
+134|7|F|154260.84|1992-05-01|4-NOT SPECIFIED|Clerk#000000711|0|lar theodolites boos|61.1089|-149.857|61.1089|-149.857|
+135|61|O|174569.88|1995-10-21|4-NOT SPECIFIED|Clerk#000000804|0|l platelets use according t|61.1024|-149.853|61.1024|-149.853|
+160|83|O|86076.86|1996-12-19|4-NOT SPECIFIED|Clerk#000000342|0|thely special sauternes wake slyly of t|61.1891|-149.906|61.1891|-149.906|
+161|17|F|19056.99|1994-08-31|2-HIGH|Clerk#000000322|0|carefully! special instructions sin|61.1891|-149.906|61.1891|-149.906|
+162|16|O|2158.13|1995-05-08|3-MEDIUM|Clerk#000000378|0|nts hinder fluffily ironic instructions. express, express excuses |61.1891|-149.906|61.1891|-149.906|
+163|88|O|125170.86|1997-09-05|3-MEDIUM|Clerk#000000379|0|y final packages. final foxes since the quickly even|61.1891|-149.906|61.1891|-149.906|
+164|1|F|202660.52|1992-10-21|5-LOW|Clerk#000000209|0|cajole ironic courts. slyly final ideas are slyly. blithely final Tiresias sub|61.1891|-149.906|61.1891|-149.906|
+165|28|F|141824.23|1993-01-30|4-NOT SPECIFIED|Clerk#000000292|0|across the blithely regular accounts. bold|61.1891|-149.906|61.1891|-149.906|
+166|109|O|93335.60|1995-09-12|2-HIGH|Clerk#000000440|0|lets. ironic, bold asymptotes kindle|61.1891|-149.906|61.1891|-149.906|
+167|121|F|52982.23|1993-01-04|4-NOT SPECIFIED|Clerk#000000731|0|s nag furiously bold excuses. fluffily iron|61.1891|-149.906|61.1891|-149.906|
+192|83|O|133002.55|1997-11-25|5-LOW|Clerk#000000483|0|y unusual platelets among the final instructions integrate rut|61.1891|-149.906|61.1891|-149.906|
+193|80|F|48053.18|1993-08-08|1-URGENT|Clerk#000000025|0|the furiously final pin|61.1891|-149.906|61.1891|-149.906|
+194|62|F|114097.63|1992-04-05|3-MEDIUM|Clerk#000000352|0|egular requests haggle slyly regular, regular pinto beans. asymptote|61.1891|-149.906|61.1891|-149.906|
+195|136|F|120053.52|1993-12-28|3-MEDIUM|Clerk#000000216|0|old forges are furiously sheaves. slyly fi|61.1891|-149.906|61.1891|-149.906|
+196|65|F|33248.04|1993-03-17|2-HIGH|Clerk#000000988|0|beans boost at the foxes. silent foxes|61.1891|-149.906|61.1891|-149.906|
+197|34|P|100290.07|1995-04-07|2-HIGH|Clerk#000000969|0|solve quickly about the even braids. carefully express deposits affix care|61.1891|-149.906|61.1891|-149.906|
+198|112|O|125792.83|1998-01-02|4-NOT SPECIFIED|Clerk#000000331|0|its. carefully ironic requests sleep. furiously express fox|61.1891|-149.906|61.1891|-149.906|
+199|53|O|80592.44|1996-03-07|2-HIGH|Clerk#000000489|0|g theodolites. special packag|61.1891|-149.906|61.1891|-149.906|
+224|4|F|155680.60|1994-06-18|4-NOT SPECIFIED|Clerk#000000642|0|r the quickly thin courts. carefully|61.1891|-149.906|61.1891|-149.906|
+225|34|P|165890.47|1995-05-25|1-URGENT|Clerk#000000177|0|s. blithely ironic accounts wake quickly fluffily special acc|61.1891|-149.906|61.1891|-149.906|
+226|128|F|180119.22|1993-03-10|2-HIGH|Clerk#000000756|0|s are carefully at the blithely ironic acc|61.1891|-149.906|61.1891|-149.906|
+227|10|O|46076.46|1995-11-10|5-LOW|Clerk#000000919|0| express instructions. slyly regul|61.1891|-149.906|61.1891|-149.906|
+228|46|F|2638.98|1993-02-25|1-URGENT|Clerk#000000562|0|es was slyly among the regular foxes. blithely regular dependenci|61.1891|-149.906|61.1891|-149.906|
+229|112|F|142290.77|1993-12-29|1-URGENT|Clerk#000000628|0|he fluffily even instructions. furiously i|61.1891|-149.906|61.1891|-149.906|
+230|103|F|107231.60|1993-10-27|1-URGENT|Clerk#000000520|0|odolites. carefully quick requ|61.1891|-149.906|61.1891|-149.906|
+231|91|F|141554.06|1994-09-29|2-HIGH|Clerk#000000446|0| packages haggle slyly after the carefully ironic instruct|61.1891|-149.906|61.1891|-149.906|
+256|125|F|106315.25|1993-10-19|4-NOT SPECIFIED|Clerk#000000834|0|he fluffily final ideas might are final accounts. carefully f|61.1891|-149.906|61.1891|-149.906|
+257|124|O|7102.74|1998-03-28|3-MEDIUM|Clerk#000000680|0|ts against the sly warhorses cajole slyly accounts|61.1891|-149.906|61.1891|-149.906|
+258|43|F|186669.10|1993-12-29|1-URGENT|Clerk#000000167|0|dencies. blithely quick packages cajole. ruthlessly final accounts|61.1891|-149.906|61.1891|-149.906|
+259|44|F|75661.70|1993-09-29|4-NOT SPECIFIED|Clerk#000000601|0|ages doubt blithely against the final foxes. carefully express deposits dazzle|61.1891|-149.906|61.1891|-149.906|
+260|106|O|179292.14|1996-12-10|3-MEDIUM|Clerk#000000960|0|lently regular pinto beans sleep after the slyly e|61.1891|-149.906|61.1891|-149.906|
+261|47|F|201003.12|1993-06-29|3-MEDIUM|Clerk#000000310|0|ully fluffily brave instructions. furiousl|61.1891|-149.906|61.1891|-149.906|
+262|31|O|108443.84|1995-11-25|4-NOT SPECIFIED|Clerk#000000551|0|l packages. blithely final pinto beans use carefu|61.1891|-149.906|61.1891|-149.906|
+263|118|F|79782.56|1994-05-17|2-HIGH|Clerk#000000088|0| pending instructions. blithely un|61.1891|-149.906|61.1891|-149.906|
+288|8|O|163794.53|1997-02-21|1-URGENT|Clerk#000000109|0|uriously final requests. even, final ideas det|61.1891|-149.906|61.1891|-149.906|
+289|104|O|131092.67|1997-02-10|3-MEDIUM|Clerk#000000103|0|sily. slyly special excuse|61.1891|-149.906|61.1891|-149.906|
+290|118|F|62814.89|1994-01-01|4-NOT SPECIFIED|Clerk#000000735|0|efully dogged deposits. furiou|61.1891|-149.906|61.1891|-149.906|
+291|142|F|66817.05|1994-03-13|1-URGENT|Clerk#000000923|0|dolites. carefully regular pinto beans cajol|64.8541|-147.813|64.8541|-147.813|
+292|23|F|30783.05|1992-01-13|2-HIGH|Clerk#000000193|0|g pinto beans will have to sleep f|64.8414|-147.606|64.8414|-147.606|
+293|31|F|37248.78|1992-10-02|2-HIGH|Clerk#000000629|0|re bold, ironic deposits. platelets c|64.8371|-147.746|64.8371|-147.746|
+294|52|F|30059.47|1993-07-16|3-MEDIUM|Clerk#000000499|0|kly according to the frays. final dolphins affix quickly |64.8151|-147.707|64.8151|-147.707|
+295|19|F|89345.99|1994-09-29|2-HIGH|Clerk#000000155|0| unusual pinto beans play. regular ideas haggle|64.8371|-147.746|64.8371|-147.746|
+320|1|O|39835.54|1997-11-21|2-HIGH|Clerk#000000573|0|ar foxes nag blithely|64.849|-147.813|64.849|-147.813|
+321|124|F|62251.15|1993-03-21|3-MEDIUM|Clerk#000000289|0|equests run. blithely final dependencies after the deposits wake caref|64.8425|-147.724|64.8425|-147.724|
+322|134|F|127068.89|1992-03-19|1-URGENT|Clerk#000000158|0|fully across the slyly bold packages. packages against the quickly regular i|64.8425|-147.724|64.8425|-147.724|
+323|40|F|79683.42|1994-03-26|1-URGENT|Clerk#000000959|0|arefully pending foxes sleep blithely. slyly express accoun|64.849|-147.826|64.849|-147.826|
+324|106|F|26868.85|1992-03-20|1-URGENT|Clerk#000000352|0| about the ironic, regular deposits run blithely against the excuses|64.815|-147.882|64.815|-147.882|
+325|41|F|71543.41|1993-10-17|5-LOW|Clerk#000000844|0|ly sometimes pending pa|64.8906|-147.628|64.8906|-147.628|
+326|76|O|229165.17|1995-06-04|2-HIGH|Clerk#000000466|0| requests. furiously ironic asymptotes mold carefully alongside of the blit|64.8276|-147.639|64.8276|-147.639|
+327|145|P|24468.16|1995-04-17|5-LOW|Clerk#000000992|0|ng the slyly final courts. slyly even escapades eat |64.8461|-147.813|64.8461|-147.813|
+352|107|F|16003.86|1994-03-08|2-HIGH|Clerk#000000932|0|ke slyly bold pinto beans. blithely regular accounts against the spe|64.8281|-147.812|64.8281|-147.812|
+353|2|F|179984.42|1993-12-31|5-LOW|Clerk#000000449|0| quiet ideas sleep. even instructions cajole slyly. silently spe|64.8377|-147.718|64.8377|-147.718|
+354|139|O|157062.70|1996-03-14|2-HIGH|Clerk#000000511|0|ly regular ideas wake across the slyly silent ideas. final deposits eat b|64.8417|-147.718|64.8417|-147.718|
+355|71|F|69447.25|1994-06-14|5-LOW|Clerk#000000532|0|s. sometimes regular requests cajole. regular, pending accounts a|64.8145|-147.772|64.8145|-147.772|
+356|148|F|162786.67|1994-06-30|4-NOT SPECIFIED|Clerk#000000944|0|as wake along the bold accounts. even, |64.8541|-147.813|64.8541|-147.813|
+357|61|O|98723.11|1996-10-09|2-HIGH|Clerk#000000301|0|e blithely about the express, final accounts. quickl|64.8169|-147.779|64.8169|-147.779|
+358|4|F|226806.66|1993-09-20|2-HIGH|Clerk#000000392|0|l, silent instructions are slyly. silently even de|64.8378|-147.71|64.8378|-147.71|
+359|79|F|142891.22|1994-12-19|3-MEDIUM|Clerk#000000934|0|n dolphins. special courts above the carefully ironic requests use|64.8436|-147.722|64.8436|-147.722|
+384|115|F|122785.82|1992-03-03|5-LOW|Clerk#000000206|0|, even accounts use furiously packages. slyly ironic pla|64.9401|-147.402|64.9401|-147.402|
+385|34|O|50724.06|1996-03-22|5-LOW|Clerk#000000600|0|hless accounts unwind bold pain|64.8426|-147.719|64.8426|-147.719|
+386|61|F|90380.40|1995-01-25|2-HIGH|Clerk#000000648|0| haggle quickly. stealthily bold asymptotes haggle among the furiously even re|64.8534|-147.811|64.8534|-147.811|
+387|4|O|130647.18|1997-01-26|4-NOT SPECIFIED|Clerk#000000768|0| are carefully among the quickly even deposits. furiously silent req|64.9341|-147.928|64.9341|-147.928|
+388|46|F|120533.46|1992-12-16|4-NOT SPECIFIED|Clerk#000000356|0|ar foxes above the furiously ironic deposits nag slyly final reque|64.8393|-147.72|64.8393|-147.72|
+389|127|F|1984.14|1994-02-17|2-HIGH|Clerk#000000062|0|ing to the regular asymptotes. final, pending foxes about the blithely sil|64.8406|-147.731|64.8406|-147.731|
+390|103|O|168562.27|1998-04-07|5-LOW|Clerk#000000404|0|xpress asymptotes use among the regular, final pinto b|64.9281|-147.865|64.9281|-147.865|
+391|112|F|13282.23|1994-11-17|2-HIGH|Clerk#000000256|0|orges thrash fluffil|64.8371|-147.716|64.8371|-147.716|
+416|41|F|71362.50|1993-09-27|5-LOW|Clerk#000000294|0| the accounts. fluffily bold depo|64.9414|-147.841|64.9414|-147.841|
+417|55|F|91982.29|1994-02-06|3-MEDIUM|Clerk#000000468|0|ironic, even packages. thinly unusual accounts sleep along the slyly unusual |64.8363|-147.79|64.8363|-147.79|
+418|95|P|33124.96|1995-04-13|4-NOT SPECIFIED|Clerk#000000643|0|. furiously ironic instruc|64.8371|-147.716|64.8371|-147.716|
+419|118|O|111597.96|1996-10-01|3-MEDIUM|Clerk#000000376|0|osits. blithely pending theodolites boost carefully|64.8591|-147.917|64.8591|-147.917|
+420|91|O|198039.23|1995-10-31|4-NOT SPECIFIED|Clerk#000000756|0|leep carefully final excuses. fluffily pending requests unwind carefully above|64.8363|-147.79|64.8363|-147.79|
+421|40|F|1084.38|1992-02-22|5-LOW|Clerk#000000405|0|egular, even packages according to the final, un|55.3801|-131.682|55.3801|-131.682|
+422|74|O|106045.89|1997-05-31|4-NOT SPECIFIED|Clerk#000000049|0|aggle carefully across the accounts. regular accounts eat fluffi|55.3073|-131.528|55.3073|-131.528|
+423|104|O|26981.31|1996-06-01|1-URGENT|Clerk#000000674|0|quests. deposits cajole quickly. furiously bold accounts haggle q|55.3801|-131.682|55.3801|-131.682|
+448|149|O|114978.03|1995-08-21|3-MEDIUM|Clerk#000000597|0| regular, express foxes use blithely. quic|55.3601|-131.681|55.3601|-131.681|
+449|97|O|41605.63|1995-07-20|2-HIGH|Clerk#000000841|0|. furiously regular theodolites affix blithely |55.3279|-131.613|55.3279|-131.613|
+450|49|P|153386.61|1995-03-05|4-NOT SPECIFIED|Clerk#000000293|0|d theodolites. boldly bold foxes since the pack|55.3129|-131.588|55.3129|-131.588|
+451|100|O|104664.40|1998-05-25|5-LOW|Clerk#000000048|0|nic pinto beans. theodolites poach carefully; |55.3801|-131.682|55.3801|-131.682|
+452|61|O|2007.48|1997-10-14|1-URGENT|Clerk#000000498|0|t, unusual instructions above the blithely bold pint|55.3801|-131.682|55.3801|-131.682|
+453|46|O|216826.73|1997-05-26|5-LOW|Clerk#000000504|0|ss foxes. furiously regular ideas sleep according to t|55.4299|-131.789|55.4299|-131.789|
+454|49|O|23198.24|1995-12-27|5-LOW|Clerk#000000890|0|dolites sleep carefully blithely regular deposits. quickly regul|55.3801|-131.682|55.3801|-131.682|
+455|13|O|138010.76|1996-12-04|1-URGENT|Clerk#000000796|0| about the final platelets. dependen|55.3507|-131.671|55.3507|-131.671|
+480|73|F|20530.97|1993-05-08|5-LOW|Clerk#000000004|0|ealthy pinto beans. fluffily regular requests along the special sheaves wake |55.3801|-131.682|55.3801|-131.682|
+481|31|F|117827.18|1992-10-08|2-HIGH|Clerk#000000230|0|ly final ideas. packages haggle fluffily|55.3394|-131.636|55.3394|-131.636|
+482|127|O|136634.34|1996-03-26|1-URGENT|Clerk#000000295|0|ts. deposits wake: final acco|55.3801|-131.682|55.3801|-131.682|
+483|35|O|39793.05|1995-07-11|2-HIGH|Clerk#000000025|0|cross the carefully final e|55.3103|-131.582|55.3103|-131.582|
+484|55|O|219920.62|1997-01-03|3-MEDIUM|Clerk#000000545|0|grouches use. furiously bold accounts maintain. bold, regular deposits|55.3801|-131.682|55.3801|-131.682|
+485|101|O|110432.76|1997-03-26|2-HIGH|Clerk#000000105|0| regular ideas nag thinly furiously s|55.3801|-131.682|55.3801|-131.682|
+486|52|O|185968.15|1996-03-11|4-NOT SPECIFIED|Clerk#000000803|0|riously dolphins. fluffily ironic requ|55.3801|-131.682|55.3801|-131.682|
+487|109|F|48502.79|1992-08-18|1-URGENT|Clerk#000000086|0|ithely unusual courts eat accordi|55.3801|-131.682|55.3801|-131.682|
+512|64|P|124661.48|1995-05-20|5-LOW|Clerk#000000814|0|ding requests. carefully express theodolites was quickly. furious|55.3801|-131.682|55.3801|-131.682|
+513|61|O|63703.92|1995-05-01|2-HIGH|Clerk#000000522|0|regular packages. pinto beans cajole carefully against the even|55.3424|-131.634|55.3424|-131.634|
+514|76|O|104585.77|1996-04-04|2-HIGH|Clerk#000000094|0| cajole furiously. slyly final excuses cajole. slyly special instructions |55.4097|-131.729|55.4097|-131.729|
+515|142|F|153720.22|1993-08-29|4-NOT SPECIFIED|Clerk#000000700|0|eposits are furiously furiously silent pinto beans. pending pack|55.3801|-131.682|55.3801|-131.682|
+516|44|O|10677.86|1998-04-21|2-HIGH|Clerk#000000305|0|lar, unusual platelets are carefully. even courts sleep bold, final pinto bea|55.3801|-131.682|55.3801|-131.682|
+517|10|O|82197.79|1997-04-07|5-LOW|Clerk#000000359|0|slyly pending deposits cajole quickly packages. furiou|55.3462|-131.658|55.3462|-131.658|
+518|145|O|223537.09|1998-02-08|2-HIGH|Clerk#000000768|0| the carefully bold accounts. quickly regular excuses are|55.3801|-131.682|55.3801|-131.682|
+519|64|O|95731.50|1997-10-31|1-URGENT|Clerk#000000985|0|ains doze furiously against the f|55.3801|-131.682|55.3801|-131.682|
+544|94|F|47627.89|1993-02-17|2-HIGH|Clerk#000000145|0|the special, final accounts. dogged dolphins|55.3801|-131.682|55.3801|-131.682|
+545|64|O|23476.12|1995-11-07|2-HIGH|Clerk#000000537|0|as. blithely final hockey players about th|55.3801|-131.682|55.3801|-131.682|
+546|145|O|14790.37|1996-11-01|2-HIGH|Clerk#000000041|0|osits sleep. slyly special dolphins about the q|55.3801|-131.682|55.3801|-131.682|
+547|100|O|96855.29|1996-06-22|3-MEDIUM|Clerk#000000976|0|ing accounts eat. carefully regular packa|55.3801|-131.682|55.3801|-131.682|
+548|124|F|99088.75|1994-09-21|1-URGENT|Clerk#000000435|0|arefully express instru|55.3801|-131.682|55.3801|-131.682|
+549|110|F|141679.41|1992-07-13|1-URGENT|Clerk#000000196|0|ideas alongside of |55.3801|-131.682|55.3801|-131.682|
+550|25|O|33123.28|1995-08-02|1-URGENT|Clerk#000000204|0|t requests. blithely |61.5856|-149.316|61.5856|-149.316|
+551|91|O|46355.83|1995-05-30|1-URGENT|Clerk#000000179|0|xpress accounts boost quic|61.5781|-149.429|61.5781|-149.429|
+576|31|O|18307.45|1997-05-13|3-MEDIUM|Clerk#000000955|0|l requests affix regular requests. final account|61.6141|-149.457|61.6141|-149.457|
+577|56|F|34768.68|1994-12-19|5-LOW|Clerk#000000154|0| deposits engage stealthil|61.5801|-149.461|61.5801|-149.461|
+578|94|O|70392.02|1997-01-10|5-LOW|Clerk#000000281|0|e blithely even packages. slyly pending platelets bes|61.9071|-150.067|61.9071|-150.067|
+579|68|O|120828.12|1998-03-11|2-HIGH|Clerk#000000862|0| regular instructions. blithely even p|61.5928|-149.392|61.5928|-149.392|
+580|61|O|88219.12|1997-07-05|2-HIGH|Clerk#000000314|0|tegrate fluffily regular accou|61.6141|-149.457|61.6141|-149.457|
+581|70|O|126066.00|1997-02-23|4-NOT SPECIFIED|Clerk#000000239|0| requests. even requests use slyly. blithely ironic |61.5792|-149.36|61.5792|-149.36|
+582|50|O|129004.81|1997-10-21|1-URGENT|Clerk#000000378|0|n pinto beans print a|61.6049|-149.463|61.6049|-149.463|
+583|49|O|127817.38|1997-03-19|3-MEDIUM|Clerk#000000792|0|efully express requests. a|61.6099|-149.328|61.6099|-149.328|
+608|26|O|62567.99|1996-02-28|3-MEDIUM|Clerk#000000995|0|nic waters wake slyly slyly expre|61.5531|-149.651|61.5531|-149.651|
+609|127|F|21088.59|1994-06-01|3-MEDIUM|Clerk#000000348|0|- ironic gifts believe furiously ca|61.6141|-149.457|61.6141|-149.457|
+610|52|O|175142.28|1995-08-02|1-URGENT|Clerk#000000610|0|totes. ironic, unusual packag|61.6141|-149.457|61.6141|-149.457|
+611|106|F|73907.63|1993-01-27|1-URGENT|Clerk#000000401|0|ounts detect furiously ac|61.5531|-149.651|61.5531|-149.651|
+612|82|F|145695.42|1992-10-21|3-MEDIUM|Clerk#000000759|0|boost quickly quickly final excuses. final foxes use bravely afte|61.6141|-149.457|61.6141|-149.457|
+613|139|O|33396.35|1995-06-18|2-HIGH|Clerk#000000172|0|ts hinder among the deposits. fluffily ironic depos|61.7321|-150.12|61.7321|-150.12|
+614|134|F|218116.21|1992-12-01|2-HIGH|Clerk#000000388|0| deposits! even, daring theodol|61.6141|-149.457|61.6141|-149.457|
+615|67|F|32890.89|1992-05-09|5-LOW|Clerk#000000388|0|t to promise asymptotes. packages haggle alongside of the fluffil|61.582|-149.441|61.582|-149.441|
+640|97|F|145495.62|1993-01-23|2-HIGH|Clerk#000000433|0|r, unusual accounts boost carefully final ideas. slyly silent theod|61.5818|-149.44|61.5818|-149.44|
+641|133|F|120626.49|1993-08-30|5-LOW|Clerk#000000175|0|ents cajole furiously about the quickly silent pac|61.6141|-149.457|61.6141|-149.457|
+642|40|F|22994.51|1993-12-16|3-MEDIUM|Clerk#000000357|0| among the requests wake slyly alongside of th|61.7321|-150.12|61.7321|-150.12|
+643|58|P|180396.95|1995-03-25|2-HIGH|Clerk#000000354|0|g dependencies. regular accounts |61.6308|-149.415|61.6308|-149.415|
+644|8|F|201268.06|1992-05-01|1-URGENT|Clerk#000000550|0| blithely unusual platelets haggle ironic, special excuses. excuses unwi|61.5801|-149.461|61.5801|-149.461|
+645|115|F|234763.73|1994-12-03|2-HIGH|Clerk#000000090|0|quickly daring theodolites across the regu|61.5811|-149.444|61.5811|-149.444|
+646|52|F|142070.65|1994-11-22|2-HIGH|Clerk#000000203|0|carefully even foxes. fina|61.6521|-149.92|61.6521|-149.92|
+647|143|O|56449.23|1997-08-07|1-URGENT|Clerk#000000270|0|egular pearls. carefully express asymptotes are. even account|61.6141|-149.307|61.6141|-149.307|
+672|109|F|89877.09|1994-04-14|5-LOW|Clerk#000000106|0|egular requests are furiously according to |61.6168|-149.328|61.6168|-149.328|
+673|80|F|21137.08|1994-03-10|1-URGENT|Clerk#000000448|0| special pinto beans use quickly furiously even depende|61.5714|-149.381|61.5714|-149.381|
+674|34|F|27204.60|1992-08-29|5-LOW|Clerk#000000448|0|ully special deposits. furiously final warhorses affix carefully. fluffily f|61.6521|-149.92|61.6521|-149.92|
+675|13|O|125188.72|1997-07-31|2-HIGH|Clerk#000000168|0|ffily between the careful|61.5858|-149.376|61.5858|-149.376|
+676|38|O|163966.67|1996-12-13|2-HIGH|Clerk#000000248|0|the final deposits. special, pending|61.5822|-149.463|61.5822|-149.463|
+677|124|F|147915.68|1993-11-24|3-MEDIUM|Clerk#000000824|0|uriously special pinto beans cajole carefully. fi|61.5861|-149.303|61.5861|-149.303|
+678|131|F|135761.05|1993-02-27|5-LOW|Clerk#000000530|0|. blithely final somas about the|61.5821|-149.438|61.5821|-149.438|
+679|49|O|8945.03|1995-12-15|2-HIGH|Clerk#000000853|0|tealthy, final pinto beans haggle slyly. pending platelets about the special, |61.6281|-149.338|61.6281|-149.338|
+704|85|O|56210.26|1996-11-21|3-MEDIUM|Clerk#000000682|0|blithely pending platelets wake alongside of the final, iron|61.5771|-149.335|61.5771|-149.335|
+705|43|O|83773.49|1997-02-13|4-NOT SPECIFIED|Clerk#000000294|0|ithely regular dependencies. express, even packages sleep slyly pending t|61.5917|-149.464|61.5917|-149.464|
+706|148|O|23973.60|1995-09-09|1-URGENT|Clerk#000000448|0|g the packages. deposits caj|61.1927|-149.86|61.1927|-149.86|
+707|118|F|58218.35|1994-11-20|3-MEDIUM|Clerk#000000199|0| ideas about the silent, bold deposits nag dolphins|61.1879|-149.85|61.1879|-149.85|
+708|32|O|100445.59|1998-07-03|3-MEDIUM|Clerk#000000101|0|lphins cajole about t|61.1814|-149.849|61.1814|-149.849|
+709|37|O|72055.87|1998-04-21|1-URGENT|Clerk#000000461|0|ons alongside of the carefully bold pinto bea|61.2104|-149.892|61.2104|-149.892|
+710|133|F|208974.42|1993-01-02|5-LOW|Clerk#000000026|0| regular, regular requests boost. fluffily re|61.2093|-149.903|61.2093|-149.903|
+711|64|F|92484.70|1993-09-23|4-NOT SPECIFIED|Clerk#000000856|0|its. fluffily regular gifts are furi|61.1481|-149.829|61.1481|-149.829|
+736|47|O|130204.17|1998-06-21|5-LOW|Clerk#000000881|0|refully of the final pi|61.2161|-149.876|61.2161|-149.876|
+737|121|F|12984.85|1992-04-26|5-LOW|Clerk#000000233|0|ake blithely express, ironic theodolites. blithely special accounts wa|61.1972|-149.75|61.1972|-149.75|
+738|22|F|114145.18|1993-03-02|4-NOT SPECIFIED|Clerk#000000669|0|ly even foxes. furiously regular accounts cajole ca|61.2066|-149.887|61.2066|-149.887|
+739|1|O|159171.69|1998-05-31|5-LOW|Clerk#000000900|0| against the slyly ironic packages nag slyly ironic|61.2161|-149.876|61.2161|-149.876|
+740|44|O|83490.99|1995-07-16|3-MEDIUM|Clerk#000000583|0|courts haggle furiously across the final, regul|61.195|-149.834|61.195|-149.834|
+741|106|O|47985.98|1998-07-07|2-HIGH|Clerk#000000295|0|ic instructions. slyly express instructions solv|61.2038|-149.808|61.2038|-149.808|
+742|103|F|207632.55|1994-12-23|5-LOW|Clerk#000000543|0|equests? slyly ironic dolphins boost carefully above the blithely|61.1228|-149.862|61.1228|-149.862|
+743|79|O|23614.89|1996-10-04|4-NOT SPECIFIED|Clerk#000000933|0|eans. furiously ironic deposits sleep carefully carefully qui|61.2005|-149.785|61.2005|-149.785|
+768|98|O|220636.82|1996-08-20|3-MEDIUM|Clerk#000000411|0|jole slyly ironic packages. slyly even idea|61.181|-149.825|61.181|-149.825|
+769|80|F|43092.76|1993-06-02|3-MEDIUM|Clerk#000000172|0|ggle furiously. ironic packages haggle slyly. bold platelets affix s|61.1867|-149.919|61.1867|-149.919|
+770|32|O|64271.75|1998-05-23|5-LOW|Clerk#000000572|0|heodolites. furiously special pinto beans cajole pac|61.1955|-149.911|61.1955|-149.911|
+771|46|O|105302.05|1995-06-17|1-URGENT|Clerk#000000105|0|s. furiously final instructions across the deposit|61.1089|-149.858|61.1089|-149.858|
+772|97|F|128234.96|1993-04-17|2-HIGH|Clerk#000000430|0|s boost blithely fluffily idle ideas? fluffily even pin|61.1805|-149.889|61.1805|-149.889|
+773|133|F|146862.27|1993-09-26|3-MEDIUM|Clerk#000000307|0|tions are quickly accounts. accounts use bold, even pinto beans. gifts ag|61.1534|-149.985|61.1534|-149.985|
+774|80|O|145857.60|1995-12-04|1-URGENT|Clerk#000000883|0|tealthily even depths|61.1901|-149.911|61.1901|-149.911|
+775|134|F|59455.61|1995-03-18|1-URGENT|Clerk#000000191|0|kly express requests. fluffily silent accounts poach furiously|61.2122|-149.734|61.2122|-149.734|
+800|56|O|87892.38|1998-07-14|2-HIGH|Clerk#000000213|0|y alongside of the pending packages? final platelets nag fluffily carefu|61.1951|-149.906|61.1951|-149.906|
+801|118|F|127717.72|1992-02-18|1-URGENT|Clerk#000000186|0|iously from the furiously enticing reques|61.2043|-149.869|61.2043|-149.869|
+802|137|F|156381.95|1995-01-05|1-URGENT|Clerk#000000516|0|posits. ironic, pending requests cajole. even theodol|61.2036|-149.869|61.2036|-149.869|
+803|16|O|27629.66|1997-04-29|5-LOW|Clerk#000000260|0|ic instructions. even deposits haggle furiously at the deposits-- regular de|61.1883|-149.886|61.1883|-149.886|
+804|50|F|94400.43|1993-03-12|3-MEDIUM|Clerk#000000931|0|s. blithely final foxes are about the packag|61.2141|-149.864|61.2141|-149.864|
+805|127|O|90042.41|1995-07-05|4-NOT SPECIFIED|Clerk#000000856|0|y according to the fluffily |61.1955|-149.782|61.1955|-149.782|
+806|131|O|26839.16|1996-06-20|2-HIGH|Clerk#000000240|0| the ironic packages wake carefully fina|61.2183|-149.894|61.2183|-149.894|
+807|145|F|222392.53|1993-11-24|3-MEDIUM|Clerk#000000012|0|refully special tithes. blithely regular accoun|61.1417|-149.864|61.1417|-149.864|
+832|29|F|68494.08|1992-04-19|5-LOW|Clerk#000000495|0|xes. bravely regular packages sleep up the furiously bold accou|61.1883|-149.883|61.1883|-149.883|
+833|56|F|49033.69|1994-02-13|3-MEDIUM|Clerk#000000437|0|ts haggle quickly across the slyl|61.2161|-149.876|61.2161|-149.876|
+834|43|F|46459.92|1994-05-23|3-MEDIUM|Clerk#000000805|0| sleep. quickly even foxes are boldly. slyly express requests use slyly|61.2193|-149.869|61.2193|-149.869|
+835|65|O|62430.67|1995-10-08|4-NOT SPECIFIED|Clerk#000000416|0|s about the carefully special foxes haggle quickly about the|61.2191|-149.888|61.2191|-149.888|
+836|70|O|72843.48|1996-11-25|4-NOT SPECIFIED|Clerk#000000729|0|ely bold excuses sleep regular ideas. furiously unusual ideas wake furiou|61.2191|-149.888|61.2191|-149.888|
+837|116|F|60918.41|1994-06-15|4-NOT SPECIFIED|Clerk#000000563|0|kages sleep slyly above the ironic, final orbits|61.2191|-149.888|61.2191|-149.888|
+838|17|O|82918.36|1998-01-29|5-LOW|Clerk#000000213|0| slyly around the slyly even|61.2191|-149.888|61.2191|-149.888|
+839|28|O|70182.63|1995-08-08|1-URGENT|Clerk#000000951|0|the carefully even platelets. furiously unusual fo|61.2191|-149.888|61.2191|-149.888|
+864|139|O|74710.74|1997-08-17|1-URGENT|Clerk#000000036|0|ly after the slyly regular deposits. express, regular asymptotes nag ca|61.2191|-149.888|61.2191|-149.888|
+865|4|F|70430.54|1993-05-04|3-MEDIUM|Clerk#000000337|0|. special packages wake after the carefully final accounts. express pinto be|61.2191|-149.888|61.2191|-149.888|
+866|40|F|4766.19|1992-11-28|3-MEDIUM|Clerk#000000718|0|ins after the even, even accounts nod blithel|61.2191|-149.888|61.2191|-149.888|
+867|26|F|7471.75|1993-11-16|3-MEDIUM|Clerk#000000877|0|pades nag quickly final, |61.2191|-149.888|61.2191|-149.888|
+868|104|F|127345.45|1992-06-09|4-NOT SPECIFIED|Clerk#000000782|0|onic theodolites print carefully. blithely dogge|61.2191|-149.888|61.2191|-149.888|
+869|136|O|58932.19|1997-01-12|2-HIGH|Clerk#000000245|0|ar sheaves are slowly. slyly even attainments boost theodolites. furiously|61.2191|-149.888|61.2191|-149.888|
+870|34|F|40492.37|1993-06-20|4-NOT SPECIFIED|Clerk#000000123|0|blithely ironic ideas nod. sly, r|61.2191|-149.888|61.2191|-149.888|
+871|16|O|172861.58|1995-11-15|5-LOW|Clerk#000000882|0|oss the ironic theodolites.|61.1891|-149.906|61.1891|-149.906|
+896|2|F|169847.63|1993-03-09|1-URGENT|Clerk#000000187|0|inal packages eat blithely according to the warhorses. furiously quiet de|61.2191|-149.888|61.2191|-149.888|
+897|49|P|57697.44|1995-03-20|1-URGENT|Clerk#000000316|0| wake quickly against |61.2191|-149.888|61.2191|-149.888|
+898|55|F|101020.75|1993-06-03|2-HIGH|Clerk#000000611|0|. unusual pinto beans haggle quickly across |61.1101|-149.857|61.1101|-149.857|
+899|109|O|125562.09|1998-04-08|5-LOW|Clerk#000000575|0|rts engage carefully final theodolites.|61.1101|-149.857|61.1101|-149.857|
+900|46|F|120073.51|1994-10-01|4-NOT SPECIFIED|Clerk#000000060|0| fluffily express deposits nag furiousl|61.1101|-149.857|61.1101|-149.857|
+901|13|O|81826.12|1998-07-21|4-NOT SPECIFIED|Clerk#000000929|0|lyly even foxes are furious, silent requests. requests about the quickly |61.1101|-149.857|61.1101|-149.857|
+902|10|F|37348.62|1994-07-27|4-NOT SPECIFIED|Clerk#000000811|0|yly final requests over the furiously regula|61.1101|-149.857|61.1101|-149.857|
+903|11|O|109351.87|1995-07-07|4-NOT SPECIFIED|Clerk#000000793|0|e slyly about the final pl|61.1101|-149.857|61.1101|-149.857|
+928|67|F|228136.49|1995-03-02|5-LOW|Clerk#000000450|0|ithely express pinto beans. |61.1101|-149.857|61.1101|-149.857|
+929|83|F|109301.02|1992-10-02|2-HIGH|Clerk#000000160|0|its. furiously even foxes affix carefully finally silent accounts. express req|61.1101|-149.857|61.1101|-149.857|
+930|131|F|199102.23|1994-12-17|1-URGENT|Clerk#000000004|0| accounts nag slyly. ironic, ironic accounts wake blithel|61.1101|-149.857|61.1101|-149.857|
+931|103|F|117909.23|1992-12-07|1-URGENT|Clerk#000000881|0|ss packages haggle furiously express, regular deposits. even, e|61.1101|-149.857|61.1101|-149.857|
+932|41|O|40234.50|1997-05-16|2-HIGH|Clerk#000000218|0|ly express instructions boost furiously reg|61.1101|-149.857|61.1101|-149.857|
+933|97|F|71349.30|1992-08-05|4-NOT SPECIFIED|Clerk#000000752|0|ial courts wake permanently against the furiously regular ideas. unusual |61.1101|-149.857|61.1101|-149.857|
+934|52|O|17213.59|1996-07-03|1-URGENT|Clerk#000000229|0|ts integrate carefully. sly, regular deposits af|61.1101|-149.857|61.1101|-149.857|
+935|50|O|97733.87|1997-09-24|5-LOW|Clerk#000000180|0|iously final deposits cajole. blithely even packages |61.1101|-149.857|61.1101|-149.857|
+960|35|F|63537.13|1994-09-21|3-MEDIUM|Clerk#000000120|0|regular accounts. requests|61.1101|-149.857|61.1101|-149.857|
+961|56|P|158893.16|1995-06-04|4-NOT SPECIFIED|Clerk#000000720|0|ons nag furiously among the quickl|61.1101|-149.857|61.1101|-149.857|
+962|37|F|98258.73|1994-05-06|5-LOW|Clerk#000000463|0|ments nag deposits. fluffily ironic a|61.1101|-149.857|61.1101|-149.857|
+963|26|F|53287.25|1994-05-26|3-MEDIUM|Clerk#000000497|0|uses haggle carefully. slyly even dependencies after the packages ha|61.1101|-149.857|61.1101|-149.857|
+964|76|O|131146.47|1995-05-20|3-MEDIUM|Clerk#000000657|0|print blithely ironic, careful theodolit|61.1101|-149.857|61.1101|-149.857|
+965|70|P|41758.44|1995-05-15|5-LOW|Clerk#000000218|0|iously special packages. slyly pending requests are carefully |64.8591|-147.917|64.8591|-147.917|
+966|14|O|120516.93|1998-04-30|2-HIGH|Clerk#000000239|0|special deposits. furious|64.8273|-147.715|64.8273|-147.715|
+967|110|F|179287.95|1992-06-21|3-MEDIUM|Clerk#000000167|0|excuses engage quickly bold dep|64.8281|-147.715|64.8281|-147.715|
+992|55|O|133665.12|1997-11-11|3-MEDIUM|Clerk#000000875|0|ts. regular pinto beans thrash carefully sl|64.8552|-147.763|64.8552|-147.763|
+993|80|O|198238.65|1995-09-10|3-MEDIUM|Clerk#000000894|0|quickly express accounts among the furiously bol|64.8481|-147.684|64.8481|-147.684|
+994|2|F|41433.48|1994-04-20|5-LOW|Clerk#000000497|0|ole. slyly bold excuses nag caref|64.8522|-147.773|64.8522|-147.773|
+995|116|P|135157.92|1995-05-31|3-MEDIUM|Clerk#000000439|0|deas. blithely final deposits play. express accounts wake blithely caref|64.8467|-147.703|64.8467|-147.703|
+996|71|O|47447.63|1997-12-29|1-URGENT|Clerk#000000497|0|arefully final packages into the slyly final requests affix blit|64.8963|-147.662|64.8963|-147.662|
+997|109|O|27561.82|1997-05-19|2-HIGH|Clerk#000000651|0|ly express depths. furiously final requests haggle furiously. carefu|64.8372|-147.796|64.8372|-147.796|
+998|32|F|65269.38|1994-11-26|4-NOT SPECIFIED|Clerk#000000956|0|ronic dolphins. ironic, bold ideas haggle furiously furious|64.8312|-147.716|64.8312|-147.716|
+999|61|F|145249.13|1993-09-05|5-LOW|Clerk#000000464|0|pitaphs sleep. regular accounts use. f|64.811|-147.71|64.811|-147.71|
+1024|4|O|176084.63|1997-12-23|5-LOW|Clerk#000000903|0| blithely. even, express theodolites cajole slyly across|64.8971|-147.663|64.8971|-147.663|
+1025|103|F|82034.03|1995-05-05|2-HIGH|Clerk#000000376|0|ross the slyly final pa|64.85|-147.699|64.85|-147.699|
+1026|73|O|36464.76|1997-06-04|5-LOW|Clerk#000000223|0|s wake blithely. special acco|64.8389|-147.743|64.8389|-147.743|
+1027|128|F|112770.89|1992-06-03|3-MEDIUM|Clerk#000000241|0|equests cajole. slyly final pinto bean|64.781|-148|64.781|-148|
+1028|70|F|153864.67|1994-01-01|2-HIGH|Clerk#000000131|0|ts are. final, silent deposits are among the fl|64.8377|-147.718|64.8377|-147.718|
+1029|130|F|47440.91|1994-06-21|2-HIGH|Clerk#000000700|0|quests sleep. slyly even foxes wake quickly final theodolites. clo|64.8248|-147.886|64.8248|-147.886|
+1030|134|F|16346.94|1994-06-15|5-LOW|Clerk#000000422|0|ully ironic accounts sleep carefully. requests are carefully alongside of the |64.818|-147.679|64.818|-147.679|
+1031|4|F|128024.71|1994-09-01|3-MEDIUM|Clerk#000000448|0|s; ironic theodolites along the carefully ex|64.8271|-147.79|64.8271|-147.79|
+1056|28|F|38446.39|1995-02-11|1-URGENT|Clerk#000000125|0|t, even deposits hang about the slyly special i|64.8451|-147.812|64.8451|-147.812|
+1057|76|F|108107.42|1992-02-20|1-URGENT|Clerk#000000124|0|cuses dazzle carefully careful, ironic pinto beans. carefully even theod|64.8311|-147.729|64.8311|-147.729|
+1058|53|F|89359.11|1993-04-26|3-MEDIUM|Clerk#000000373|0|kly pending courts haggle. blithely regular sheaves integrate carefully fi|64.8454|-147.855|64.8454|-147.855|
+1059|127|F|198360.22|1994-02-27|1-URGENT|Clerk#000000104|0|en accounts. carefully bold packages cajole daringly special depende|64.8302|-147.744|64.8302|-147.744|
+1060|140|F|121994.04|1993-02-21|3-MEDIUM|Clerk#000000989|0|l platelets sleep quickly slyly special requests. furiously |64.8113|-147.91|64.8113|-147.91|
+1061|103|O|166947.75|1998-05-15|5-LOW|Clerk#000000576|0|uests sleep at the packages. fur|64.8271|-147.789|64.8271|-147.789|
+1062|106|O|39805.04|1997-01-15|1-URGENT|Clerk#000000152|0|eposits use blithely |64.8451|-147.698|64.8451|-147.698|
+1063|37|F|41392.31|1994-04-02|2-HIGH|Clerk#000000024|0|deposits nag quickly regular deposits. quickl|64.8586|-147.69|64.8586|-147.69|
+1088|148|F|47120.41|1992-05-21|5-LOW|Clerk#000000347|0|counts are blithely. platelets print. carefully |64.8507|-147.702|64.8507|-147.702|
+1089|49|O|103192.74|1996-05-04|4-NOT SPECIFIED|Clerk#000000226|0|ns haggle ruthlessly. even requests are quickly abov|64.8371|-147.716|64.8371|-147.716|
+1090|19|O|32929.30|1997-11-15|2-HIGH|Clerk#000000300|0| furiously regular platelets haggle along the slyly unusual foxes! |64.8449|-147.743|64.8449|-147.743|
+1091|83|O|35795.22|1996-08-27|1-URGENT|Clerk#000000549|0| even pinto beans haggle quickly alongside of the eve|64.8475|-147.706|64.8475|-147.706|
+1092|124|P|85552.21|1995-03-04|3-MEDIUM|Clerk#000000006|0|re quickly along the blithe|64.8452|-147.714|64.8452|-147.714|
+1093|101|O|79189.58|1997-07-31|4-NOT SPECIFIED|Clerk#000000159|0| after the carefully ironic requests. carefully ironic packages wake fluffil|64.8125|-147.787|64.8125|-147.787|
+1094|145|O|9006.25|1997-12-24|3-MEDIUM|Clerk#000000570|0|beans affix furiously about the pending, even deposits. finally pendi|55.3801|-131.682|55.3801|-131.682|
+1095|145|O|178491.24|1995-08-22|3-MEDIUM|Clerk#000000709|0|sly bold requests cajole carefully according to|55.3801|-131.682|55.3801|-131.682|
+1120|140|O|107958.62|1997-11-07|3-MEDIUM|Clerk#000000319|0|lly special requests. slyly pending platelets are quickly pending requ|55.3801|-131.682|55.3801|-131.682|
+1121|29|O|241837.88|1997-01-13|3-MEDIUM|Clerk#000000541|0|r escapades. deposits above the fluffily bold requests hag|55.3801|-131.682|55.3801|-131.682|
+1122|121|O|179747.47|1997-01-10|1-URGENT|Clerk#000000083|0|uffily carefully final theodolites. furiously express packages affix|55.3801|-131.682|55.3801|-131.682|
+1123|73|O|93259.93|1996-08-03|3-MEDIUM|Clerk#000000929|0|uriously pending requests. slyly regular instruction|55.3801|-131.682|55.3801|-131.682|
+1124|80|O|141858.97|1998-07-30|5-LOW|Clerk#000000326|0|regular pinto beans along the fluffily silent packages|55.3599|-131.687|55.3599|-131.687|
+1125|25|F|80438.38|1994-10-27|2-HIGH|Clerk#000000510|0|ithely final requests. i|55.4381|-131.803|55.4381|-131.803|
+1126|145|O|59982.31|1998-01-28|4-NOT SPECIFIED|Clerk#000000928|0|d slyly regular ideas: special ideas believe slyly. slyly ironic sheaves w|55.3751|-131.718|55.3751|-131.718|
+1127|58|O|103320.91|1995-09-19|4-NOT SPECIFIED|Clerk#000000397|0|usly silent, regular pinto beans. blithely express requests boos|55.3421|-131.641|55.3421|-131.641|
+1152|49|F|51775.54|1994-08-14|4-NOT SPECIFIED|Clerk#000000496|0|equests. deposits ab|55.3408|-131.64|55.3408|-131.64|
+1153|121|O|220727.97|1996-04-18|5-LOW|Clerk#000000059|0| across the pending deposi|55.2978|-131.534|55.2978|-131.534|
+1154|37|F|192417.85|1992-02-15|1-URGENT|Clerk#000000268|0|old asymptotes are special requests. blithely even deposits sleep furiously|55.3801|-131.682|55.3801|-131.682|
+1155|149|O|126902.81|1997-10-06|2-HIGH|Clerk#000000164|0|c deposits haggle among the ironic, even requests. carefully ironic sheaves n|55.3801|-131.682|55.3801|-131.682|
+1156|133|O|217682.81|1996-10-19|1-URGENT|Clerk#000000200|0| blithely ironic dolphins. furiously pendi|55.3421|-131.622|55.3421|-131.622|
+1157|97|O|85394.06|1998-01-14|4-NOT SPECIFIED|Clerk#000000207|0|out the regular excuses boost carefully against the furio|55.3801|-131.682|55.3801|-131.682|
+1158|142|O|31075.51|1996-06-30|2-HIGH|Clerk#000000549|0|integrate slyly furiously ironic deposit|55.3801|-131.682|55.3801|-131.682|
+1159|70|F|55553.68|1992-09-18|3-MEDIUM|Clerk#000000992|0|ts may sleep. requests according to the|55.3801|-131.682|55.3801|-131.682|
+1184|89|O|39700.29|1997-10-26|5-LOW|Clerk#000000777|0|iously even packages haggle fluffily care|55.3267|-131.523|55.3267|-131.523|
+1185|74|F|47033.21|1992-08-24|5-LOW|Clerk#000000344|0| even escapades are. package|55.3522|-131.685|55.3522|-131.685|
+1186|59|O|82026.18|1996-08-15|4-NOT SPECIFIED|Clerk#000000798|0|ingly regular pinto beans: instructi|55.5351|-133.014|55.5351|-133.014|
+1187|134|F|85948.02|1992-11-20|3-MEDIUM|Clerk#000000047|0|s after the furiously final deposits boost slyly under the|55.5351|-133.014|55.5351|-133.014|
+1188|20|O|54655.07|1996-04-11|2-HIGH|Clerk#000000256|0|ully ironic deposits. slyl|55.5351|-133.014|55.5351|-133.014|
+1189|46|F|71017.99|1994-04-09|1-URGENT|Clerk#000000243|0|f the even accounts. courts print blithely ironic accounts. sile|55.5351|-133.014|55.5351|-133.014|
+1190|13|O|31043.39|1997-03-16|5-LOW|Clerk#000000575|0|ccounts above the foxes integrate carefully after the |55.5351|-133.014|55.5351|-133.014|
+1191|112|O|28623.04|1995-11-07|3-MEDIUM|Clerk#000000011|0|uests nag furiously. carefully even requests|55.4691|-132.855|55.4691|-132.855|
+1216|122|F|68056.57|1992-12-07|5-LOW|Clerk#000000918|0|nal foxes around the e|55.5511|-133.081|55.5511|-133.081|
+1217|7|F|40982.08|1992-04-26|4-NOT SPECIFIED|Clerk#000000538|0| foxes nag quickly. ironic excuses nod. blithely pending|55.5351|-133.014|55.5351|-133.014|
+1218|10|F|99834.47|1994-06-20|4-NOT SPECIFIED|Clerk#000000994|0|s cajole. special, silent deposits about the theo|55.5531|-133.097|55.5531|-133.097|
+1219|28|O|10163.56|1995-10-05|3-MEDIUM|Clerk#000000800|0|od carefully. slyly final dependencies across the even fray|55.5351|-133.014|55.5351|-133.014|
+1220|49|O|122157.14|1996-08-29|1-URGENT|Clerk#000000712|0|inal theodolites wake. fluffily ironic asymptotes cajol|55.4726|-131.793|55.4726|-131.793|
+1221|14|F|117397.16|1992-04-19|4-NOT SPECIFIED|Clerk#000000852|0| detect against the silent, even deposits. carefully ironic|55.3801|-131.682|55.3801|-131.682|
+1222|10|F|47623.94|1993-02-05|3-MEDIUM|Clerk#000000811|0|theodolites use quickly even accounts. carefully final asympto|55.3801|-131.682|55.3801|-131.682|
+1223|10|O|26714.67|1996-05-25|4-NOT SPECIFIED|Clerk#000000238|0|posits was blithely fr|55.3801|-131.682|55.3801|-131.682|
+1248|49|F|210713.88|1992-01-02|1-URGENT|Clerk#000000890|0|t the carefully regular dugouts. s|61.5745|-149.562|61.5745|-149.562|
+1249|149|F|45889.09|1994-01-05|1-URGENT|Clerk#000000095|0|al ideas sleep above the pending pin|61.7321|-150.12|61.7321|-150.12|
+1250|37|F|12907.62|1992-09-29|4-NOT SPECIFIED|Clerk#000000652|0|ts after the fluffily pending instructions use slyly about the s|61.5421|-149.419|61.5421|-149.419|
+1251|38|O|109536.55|1997-10-30|1-URGENT|Clerk#000000276|0|, brave sauternes. deposits boost fluffily.|61.5722|-149.702|61.5722|-149.702|
+1252|149|O|93403.05|1997-08-04|5-LOW|Clerk#000000348|0|ng the slyly regular excuses. special courts nag furiously blithely e|61.5743|-149.405|61.5743|-149.405|
+1253|115|F|92730.74|1993-01-26|1-URGENT|Clerk#000000775|0| requests sleep furiously even foxes. ruthless packag|61.578|-149.441|61.578|-149.441|
+1254|70|O|94649.25|1995-12-22|1-URGENT|Clerk#000000607|0| pinto beans. carefully regular request|61.5826|-149.427|61.5826|-149.427|
+1255|122|F|62518.31|1994-05-30|4-NOT SPECIFIED|Clerk#000000798|0|ct slyly regular accounts. quick|61.5586|-149.351|61.5586|-149.351|
+1280|97|F|91664.85|1993-01-11|5-LOW|Clerk#000000160|0|posits thrash quickly after the theodolites. furiously iro|61.5844|-149.442|61.5844|-149.442|
+1281|62|F|165454.51|1994-12-11|1-URGENT|Clerk#000000430|0|counts. carefully pending accounts eat |61.5817|-149.472|61.5817|-149.472|
+1282|116|F|61297.42|1992-02-29|4-NOT SPECIFIED|Clerk#000000168|0|he quickly special packages. furiously final re|61.6141|-149.457|61.6141|-149.457|
+1283|118|O|202623.92|1996-08-30|4-NOT SPECIFIED|Clerk#000000260|0| pinto beans boost slyly ac|61.5761|-149.602|61.5761|-149.602|
+1284|134|O|106122.38|1996-01-07|2-HIGH|Clerk#000000492|0|s. blithely silent deposits s|61.6141|-149.457|61.6141|-149.457|
+1285|11|F|139124.72|1992-06-01|1-URGENT|Clerk#000000423|0|cial deposits cajole after the ironic requests. p|61.58|-149.434|61.58|-149.434|
+1286|109|F|207291.83|1993-05-14|4-NOT SPECIFIED|Clerk#000000939|0| deposits use carefully from the excuses. slyly bold p|61.6002|-149.429|61.6002|-149.429|
+1287|19|F|131432.42|1994-07-05|2-HIGH|Clerk#000000288|0|ly ironic dolphins integrate furiously among the final packages. st|61.569|-149.347|61.569|-149.347|
+1312|112|F|58111.00|1994-05-19|3-MEDIUM|Clerk#000000538|0|n, express accounts across the ironic|61.5812|-149.448|61.5812|-149.448|
+1313|148|F|46598.65|1994-09-13|1-URGENT|Clerk#000000774|0|ld accounts. regular deposits cajole. ironically pending theodolites use car|61.6141|-149.457|61.6141|-149.457|
+1314|143|F|56207.66|1994-05-13|3-MEDIUM|Clerk#000000485|0|ickly blithe packages nod ideas. furiously bold braids boost around the car|61.6141|-149.457|61.6141|-149.457|
+1315|22|O|121935.23|1998-03-22|5-LOW|Clerk#000000840|0|final theodolites alongside of the carefu|61.6141|-149.457|61.6141|-149.457|
+1316|16|F|163746.47|1993-12-03|1-URGENT|Clerk#000000857|0|ully bold theodolites? pending, bold pin|61.5969|-149.367|61.5969|-149.367|
+1317|100|P|139714.71|1995-05-19|2-HIGH|Clerk#000000373|0|sts. furiously special deposits lose fur|61.58|-149.4|61.58|-149.4|
+1318|128|O|81663.65|1998-06-27|3-MEDIUM|Clerk#000000581|0|s hang bold requests. pending, re|61.5848|-149.445|61.5848|-149.445|
+1319|32|O|31103.83|1996-09-27|2-HIGH|Clerk#000000257|0|y across the ruthlessly ironic accounts. unusu|61.5811|-149.444|61.5811|-149.444|
+1344|17|F|43809.37|1992-04-16|5-LOW|Clerk#000000178|0|omise close, silent requests. pending theodolites boost pending |61.5733|-149.389|61.5733|-149.389|
+1345|95|F|111207.93|1992-10-28|5-LOW|Clerk#000000447|0| regular tithes. quickly fluffy de|61.6141|-149.457|61.6141|-149.457|
+1346|76|F|171975.62|1992-06-18|2-HIGH|Clerk#000000374|0|ges sleep quickly-- even pint|61.5952|-149.436|61.5952|-149.436|
+1347|41|O|173444.60|1997-06-20|5-LOW|Clerk#000000977|0|he furiously even foxes use carefully express req|61.5421|-149.419|61.5421|-149.419|
+1348|19|O|94135.77|1998-04-18|5-LOW|Clerk#000000206|0|tly. quickly even deposi|61.5783|-149.362|61.5783|-149.362|
+1349|64|O|46376.09|1997-10-26|1-URGENT|Clerk#000000543|0|yly! blithely special theodolites cajole. unusual, reg|61.7321|-150.12|61.7321|-150.12|
+1350|52|F|49305.98|1993-08-24|1-URGENT|Clerk#000000635|0|iously about the blithely special a|61.5691|-149.328|61.5691|-149.328|
+1351|106|O|24637.96|1998-04-20|1-URGENT|Clerk#000000012|0| cajole. regular, special re|61.6141|-149.457|61.6141|-149.457|
+1376|47|O|23984.88|1997-05-04|4-NOT SPECIFIED|Clerk#000000730|0|der furiously final, final frets. carefull|61.5819|-149.3|61.5819|-149.3|
+1377|20|O|108334.30|1998-04-24|4-NOT SPECIFIED|Clerk#000000625|0|lly across the blithely express accounts. ironic excuses promise carefully de|61.6431|-149.289|61.6431|-149.289|
+1378|20|O|118495.12|1996-03-09|4-NOT SPECIFIED|Clerk#000000705|0| furiously even tithes cajole slyly among the quick|61.6431|-149.292|61.6431|-149.292|
+1379|65|O|84627.76|1998-05-25|5-LOW|Clerk#000000861|0|y deposits are caref|61.6228|-149.313|61.6228|-149.313|
+1380|137|O|94969.41|1996-07-07|3-MEDIUM|Clerk#000000969|0|inal deposits wake slyly daringly even requests. bold, even foxe|61.2125|-149.894|61.2125|-149.894|
+1381|127|O|58212.22|1998-05-25|3-MEDIUM|Clerk#000000107|0|even requests breach after the bold, ironic instructions. slyly even|61.1879|-149.886|61.1879|-149.886|
+1382|133|F|173522.71|1993-08-17|5-LOW|Clerk#000000241|0|fully final packages sl|61.1594|-149.835|61.1594|-149.835|
+1383|121|F|34797.72|1993-04-27|2-HIGH|Clerk#000000785|0|ts. express requests sleep blithel|61.2123|-149.854|61.2123|-149.854|
+1408|55|O|183965.61|1997-12-26|4-NOT SPECIFIED|Clerk#000000942|0|t the quickly final asymptotes. unusual|61.1951|-149.945|61.1951|-149.945|
+1409|143|F|72440.52|1992-12-31|4-NOT SPECIFIED|Clerk#000000065|0|ructions. furiously unusual excuses are regular, unusual theodolites. fin|61.2138|-149.856|61.2138|-149.856|
+1410|113|O|114879.19|1997-04-12|5-LOW|Clerk#000000123|0|iously along the bravely regular dolphins. pinto beans cajole furiously sp|61.1255|-149.864|61.1255|-149.864|
+1411|95|F|164462.61|1994-12-21|2-HIGH|Clerk#000000566|0|s. furiously special excuses across the pending pinto beans haggle sp|61.2066|-149.808|61.2066|-149.808|
+1412|53|F|78676.54|1993-03-13|4-NOT SPECIFIED|Clerk#000000083|0|uffily daring theodolit|61.2138|-149.896|61.2138|-149.896|
+1413|91|O|75733.58|1997-06-14|3-MEDIUM|Clerk#000000342|0|, ironic instructions. carefully even packages dazzle|61.2161|-149.876|61.2161|-149.876|
+1414|77|O|38057.81|1995-08-16|1-URGENT|Clerk#000000883|0|ccounts. ironic foxes haggle car|61.1594|-149.888|61.1594|-149.888|
+1415|79|F|24654.79|1994-05-29|4-NOT SPECIFIED|Clerk#000000601|0|rays. blithely final ideas affix quickl|61.1806|-149.775|61.1806|-149.775|
+1440|98|O|50201.16|1995-08-10|5-LOW|Clerk#000000956|0| pending requests. closely s|61.1101|-149.857|61.1101|-149.857|
+1441|122|O|156477.94|1997-03-06|4-NOT SPECIFIED|Clerk#000000156|0|ter the excuses. ironic dependencies m|61.1541|-149.958|61.1541|-149.958|
+1442|112|F|7108.12|1994-07-05|4-NOT SPECIFIED|Clerk#000000935|0|nal pinto beans. slyly ironic ideas cajol|61.1268|-149.947|61.1268|-149.947|
+1443|44|O|44672.03|1996-12-16|5-LOW|Clerk#000000185|0|x blithely against the carefully final somas. even asymptotes are. quickly spe|61.0931|-149.785|61.0931|-149.785|
+1444|134|F|207907.60|1994-12-06|3-MEDIUM|Clerk#000000783|0|ove the bold accounts cajole fluffily about|61.1901|-149.892|61.1901|-149.892|
+1445|115|F|154653.32|1995-01-10|3-MEDIUM|Clerk#000000211|0|even packages wake fluffily |61.2183|-149.889|61.2183|-149.889|
+1446|41|O|27663.16|1998-02-16|5-LOW|Clerk#000000274|0|lly regular notornis above the requests sleep final accounts! |61.2164|-149.882|61.2164|-149.882|
+1447|91|F|108171.38|1992-10-15|2-HIGH|Clerk#000000880|0|inly against the blithely pending excuses. regular, pe|61.2161|-149.876|61.2161|-149.876|
+1472|149|O|65331.05|1996-10-06|5-LOW|Clerk#000000303|0|y special dolphins around the final dependencies wake quick|61.219|-149.792|61.219|-149.792|
+1473|94|O|80624.38|1997-03-17|3-MEDIUM|Clerk#000000960|0|furiously close accoun|61.2188|-149.892|61.2188|-149.892|
+1474|70|F|51697.18|1995-01-09|1-URGENT|Clerk#000000438|0|detect quickly above the carefully even |61.2143|-149.837|61.2143|-149.837|
+1475|5|O|185496.66|1997-11-12|2-HIGH|Clerk#000000972|0|cally final packages boost. blithely ironic packa|61.1608|-149.835|61.1608|-149.835|
+1476|145|O|18795.62|1996-06-27|2-HIGH|Clerk#000000673|0|ding accounts hinder alongside of the quickly pending requests. fluf|61.1886|-149.944|61.1886|-149.944|
+1477|76|O|231831.35|1997-08-24|5-LOW|Clerk#000000612|0|ly bold foxes. final ideas would cajo|61.1201|-149.89|61.1201|-149.89|
+1478|50|O|20791.50|1997-08-03|2-HIGH|Clerk#000000827|0|lessly. carefully express|61.1201|-149.89|61.1201|-149.89|
+1479|16|O|31471.04|1995-12-16|4-NOT SPECIFIED|Clerk#000000697|0|he furiously even foxes. thinly bold deposits|61.1585|-149.872|61.1585|-149.872|
+1504|2|F|89399.40|1992-08-28|3-MEDIUM|Clerk#000000381|0|, brave deposits. bold de|61.195|-149.892|61.195|-149.892|
+1505|37|F|55892.35|1992-08-21|2-HIGH|Clerk#000000544|0|s. slyly ironic packages cajole. carefully regular packages haggle |61.0895|-149.694|61.0895|-149.694|
+1506|148|F|195844.84|1992-09-21|3-MEDIUM|Clerk#000000620|0| dependencies. accounts affix blithely slowly unusual deposits. slyly regular |61.2201|-149.831|61.2201|-149.831|
+1507|121|F|96166.92|1993-10-14|3-MEDIUM|Clerk#000000305|0|stealthy, ironic de|61.1663|-149.867|61.1663|-149.867|
+1508|103|O|151282.65|1998-04-10|5-LOW|Clerk#000000117|0| after the furiously regular pinto beans hang slyly quickly ironi|61.2138|-149.906|61.2138|-149.906|
+1509|64|F|180455.98|1993-07-08|5-LOW|Clerk#000000770|0|the regular ideas. regul|61.2193|-149.902|61.2193|-149.902|
+1510|53|O|154590.05|1996-09-17|5-LOW|Clerk#000000128|0|ld carefully. furiously final asymptotes haggle furiously|61.1201|-149.89|61.1201|-149.89|
+1511|79|O|59651.38|1996-12-22|4-NOT SPECIFIED|Clerk#000000386|0|ts above the depend|61.1601|-149.984|61.1601|-149.984|
+1536|94|O|5184.26|1997-01-26|3-MEDIUM|Clerk#000000117|0|ges are! furiously final deposits cajole iron|61.1101|-149.857|61.1101|-149.857|
+1537|109|F|108317.51|1992-02-15|4-NOT SPECIFIED|Clerk#000000862|0|g to the even deposits. ironic, final packages |61.1101|-149.857|61.1101|-149.857|
+1538|29|O|179554.41|1995-06-18|4-NOT SPECIFIED|Clerk#000000258|0| instructions. regular theod|61.1101|-149.857|61.1101|-149.857|
+1539|112|F|39612.63|1995-03-10|5-LOW|Clerk#000000840|0|nstructions boost pa|61.1101|-149.857|61.1101|-149.857|
+1540|16|F|128014.15|1992-08-05|2-HIGH|Clerk#000000927|0|r ideas hinder blithe|61.1101|-149.857|61.1101|-149.857|
+1541|94|P|47286.32|1995-05-18|1-URGENT|Clerk#000000906|0|y. slyly ironic warhorses around the furiously regul|61.1101|-149.857|61.1101|-149.857|
+1542|143|F|132972.24|1993-09-15|3-MEDIUM|Clerk#000000435|0|t the furiously close deposits do was f|61.1101|-149.857|61.1101|-149.857|
+1543|52|O|139047.22|1997-02-20|1-URGENT|Clerk#000000398|0|unts. furiously pend|61.1101|-149.857|61.1101|-149.857|
+1568|17|O|76119.72|1997-01-30|4-NOT SPECIFIED|Clerk#000000554|0|d notornis. carefully |61.1101|-149.857|61.1101|-149.857|
+1569|104|O|87803.55|1998-04-02|5-LOW|Clerk#000000786|0|orbits. fluffily even decoys serve blithely. furiously furious realms nag acro|61.1101|-149.857|61.1101|-149.857|
+1570|124|O|35589.57|1998-03-16|1-URGENT|Clerk#000000745|0|pinto beans haggle furiousl|61.1101|-149.857|61.1101|-149.857|
+1571|103|F|151404.78|1992-12-05|2-HIGH|Clerk#000000565|0|ously furiously bold warthogs. slyly ironic instructions are quickly a|61.1101|-149.857|61.1101|-149.857|
+1572|11|O|47232.79|1996-02-24|2-HIGH|Clerk#000000994|0|fluffily ironic accounts haggle blithely final platelets! slyly regular foxes|61.1101|-149.857|61.1101|-149.857|
+1573|148|F|86918.57|1992-12-28|2-HIGH|Clerk#000000940|0|ess, ironic deposits use along the carefu|61.1101|-149.857|61.1101|-149.857|
+1574|134|O|179923.54|1996-12-12|3-MEDIUM|Clerk#000000809|0| ideas hinder after the carefully unusual |61.1101|-149.857|61.1101|-149.857|
+1575|145|O|197031.52|1995-09-13|3-MEDIUM|Clerk#000000497|0|. furiously regular dep|61.1101|-149.857|61.1101|-149.857|
+1600|94|F|130515.61|1993-03-03|3-MEDIUM|Clerk#000000627|0|tions cajole quietly above the regular, silent requests. slyly fin|61.1101|-149.857|61.1101|-149.857|
+1601|53|F|73962.95|1994-08-27|5-LOW|Clerk#000000469|0|ent deposits are ca|61.1101|-149.857|61.1101|-149.857|
+1602|1|F|4225.26|1993-08-05|5-LOW|Clerk#000000660|0|deposits. busily silent instructions haggle furiously. fin|61.1101|-149.857|61.1101|-149.857|
+1603|2|F|29305.47|1993-07-31|4-NOT SPECIFIED|Clerk#000000869|0|s. slyly silent deposits boo|61.1101|-149.857|61.1101|-149.857|
+1604|113|F|107139.29|1993-07-17|5-LOW|Clerk#000000512|0|lithely silent waters. blithely unusual packages alongside |61.1101|-149.857|61.1101|-149.857|
+1605|58|O|130687.64|1998-04-24|4-NOT SPECIFIED|Clerk#000000616|0|sleep furiously? ruthless, even pinto beans |61.1101|-149.857|61.1101|-149.857|
+1606|53|O|115877.40|1997-04-17|4-NOT SPECIFIED|Clerk#000000550|0|r requests. quickly even platelets breach before the ironically|61.1101|-149.857|61.1101|-149.857|
+1607|149|O|166335.03|1995-12-16|2-HIGH|Clerk#000000498|0| bold, pending foxes haggle. slyly silent |61.1101|-149.857|61.1101|-149.857|
+1632|67|O|183286.33|1997-01-08|3-MEDIUM|Clerk#000000351|0|onic requests are accounts. bold a|61.1101|-149.857|61.1101|-149.857|
+1633|16|O|52359.51|1995-10-14|2-HIGH|Clerk#000000666|0|y silent accounts sl|61.1101|-149.857|61.1101|-149.857|
+1634|70|O|145898.47|1996-09-10|1-URGENT|Clerk#000000360|0|arefully blithely ironic requests. slyly unusual instructions alongside|61.1101|-149.857|61.1101|-149.857|
+1635|4|O|70232.26|1997-02-13|3-MEDIUM|Clerk#000000958|0|s. slyly ironic requests affix slyly |61.1101|-149.857|61.1101|-149.857|
+1636|79|O|172021.87|1997-06-17|3-MEDIUM|Clerk#000000457|0|ding requests. slyly ironic courts wake quickl|61.1101|-149.857|61.1101|-149.857|
+1637|73|F|180912.15|1995-02-08|4-NOT SPECIFIED|Clerk#000000189|0| final accounts. blithely silent ideas cajole bravely. carefully express |61.1101|-149.857|61.1101|-149.857|
+1638|139|O|172436.30|1997-08-13|2-HIGH|Clerk#000000643|0|he fluffily regular asymp|61.1101|-149.857|61.1101|-149.857|
+1639|5|O|104166.56|1995-08-20|4-NOT SPECIFIED|Clerk#000000939|0|haggle furiously. final requests detect furious|61.1101|-149.857|61.1101|-149.857|
+1664|64|O|178060.22|1996-03-03|1-URGENT|Clerk#000000090|0|y quickly even asymptotes. furiously regular packages haggle quickly fin|61.1101|-149.857|61.1101|-149.857|
+1665|76|F|4819.91|1994-05-08|2-HIGH|Clerk#000000920|0|ly regular packages are fluffily even ideas. fluffily final|61.1101|-149.857|61.1101|-149.857|
+1666|95|O|128367.97|1995-10-18|1-URGENT|Clerk#000000849|0|ffily pending dependencies wake fluffily. pending, final accounts |61.1101|-149.857|61.1101|-149.857|
+1667|5|O|125030.37|1997-10-10|2-HIGH|Clerk#000000103|0|e accounts. slyly express accounts must are a|64.8459|-147.759|64.8459|-147.759|
+1668|142|O|137576.19|1997-07-12|4-NOT SPECIFIED|Clerk#000000148|0|eodolites. carefully dogged dolphins haggle q|64.8426|-147.725|64.8426|-147.725|
+1669|2|O|24362.39|1997-06-09|3-MEDIUM|Clerk#000000663|0|er ironic requests detect furiously blithely sp|64.9401|-147.402|64.9401|-147.402|
+1670|25|O|89999.72|1997-05-24|2-HIGH|Clerk#000000320|0|unusual dependencies. furiously special platelets main|64.9401|-147.402|64.9401|-147.402|
+1671|35|O|104391.11|1996-07-27|4-NOT SPECIFIED|Clerk#000000275|0|ly. slyly pending requests was above the |64.8331|-147.647|64.8331|-147.647|
+1696|4|O|102665.03|1998-01-08|4-NOT SPECIFIED|Clerk#000000041|0|bravely bold accounts above the quickly bold|64.8371|-147.716|64.8371|-147.716|
+1697|76|O|122621.31|1996-10-07|1-URGENT|Clerk#000000815|0|o x-ray blithely. pl|64.8574|-147.759|64.8574|-147.759|
+1698|40|O|141118.87|1997-04-23|2-HIGH|Clerk#000000432|0|slyly. carefully express deposit|64.836|-147.727|64.836|-147.727|
+1699|85|F|66408.29|1993-12-30|1-URGENT|Clerk#000000125|0|jole blithely. furiously un|64.8132|-147.76|64.8132|-147.76|
+1700|65|O|89143.36|1996-06-15|3-MEDIUM|Clerk#000000328|0|ely final dolphins wake sometimes above the quietly regular deposits. fur|64.8451|-147.96|64.8451|-147.96|
+1701|130|F|72835.95|1992-05-19|2-HIGH|Clerk#000000395|0|furiously. regular, close theodoli|64.8891|-147.851|64.8891|-147.851|
+1702|67|P|194119.31|1995-05-07|2-HIGH|Clerk#000000300|0|around the carefully final deposits cajole carefully according to the b|64.8151|-147.707|64.8151|-147.707|
+1703|134|F|121220.59|1993-01-28|3-MEDIUM|Clerk#000000463|0| pinto beans poach. bold courts boost. regular, express deposits at|64.8363|-147.803|64.8363|-147.803|
+1728|64|O|131604.34|1996-05-22|2-HIGH|Clerk#000000711|0|beans. slyly regular instructions sleep! slyly final packages|64.8298|-147.611|64.8298|-147.611|
+1729|133|F|12137.76|1992-05-19|2-HIGH|Clerk#000000158|0|pending foxes wake. accounts|64.8989|-147.701|64.8989|-147.701|
+1730|124|O|150886.49|1998-07-24|5-LOW|Clerk#000000794|0| fluffily pending deposits serve. furiously even requests wake furiou|64.8371|-147.716|64.8371|-147.716|
+1731|128|O|190490.78|1996-01-06|1-URGENT|Clerk#000000268|0|lithely regular, final instructions. ironic, express packages are above|64.8147|-147.706|64.8147|-147.706|
+1732|146|F|179854.51|1993-11-29|5-LOW|Clerk#000000903|0|inal requests integrate dolph|64.8451|-147.812|64.8451|-147.812|
+1733|148|O|165489.52|1996-05-12|2-HIGH|Clerk#000000789|0|e carefully according to the accounts. furiously pending instructions sleep|64.8386|-147.788|64.8386|-147.788|
+1734|7|F|44002.53|1994-06-11|2-HIGH|Clerk#000000722|0| final ideas haggle. blithely quick foxes sleep busily bold ideas. i|64.8372|-147.768|64.8372|-147.768|
+1735|22|F|98541.95|1992-12-27|1-URGENT|Clerk#000000458|0|ully idle requests wake qu|64.8151|-147.707|64.8151|-147.707|
+1760|115|O|82151.12|1996-05-17|5-LOW|Clerk#000000917|0| deposits. busily regular deposits wake blithely along the furiously even re|64.843|-147.722|64.843|-147.722|
+1761|106|F|211925.95|1993-12-24|2-HIGH|Clerk#000000817|0|efully slyly bold frets. packages boost b|64.8426|-147.725|64.8426|-147.725|
+1762|77|F|202227.17|1994-08-20|4-NOT SPECIFIED|Clerk#000000653|0|ly ironic packages. furi|64.8615|-147.723|64.8615|-147.723|
+1763|121|O|140685.01|1996-10-29|2-HIGH|Clerk#000000321|0|es. bold dependencies haggle furiously along |64.8694|-147.067|64.8694|-147.067|
+1764|29|F|47384.71|1992-03-25|1-URGENT|Clerk#000000182|0|. slyly final packages integrate carefully acro|64.8404|-147.724|64.8404|-147.724|
+1765|73|O|36551.43|1995-12-03|4-NOT SPECIFIED|Clerk#000000490|0| regular excuses wake slyly|64.9686|-147.577|64.9686|-147.577|
+1766|139|O|41032.81|1996-10-12|2-HIGH|Clerk#000000983|0|unusual deposits affix quickly beyond the carefully s|64.8497|-147.732|64.8497|-147.732|
+1767|25|P|136582.60|1995-03-14|2-HIGH|Clerk#000000327|0|eposits use carefully carefully regular platelets. quickly regular packages al|64.8861|-147.587|64.8861|-147.587|
+1792|49|F|107919.86|1993-11-09|5-LOW|Clerk#000000102|0|ructions haggle along the pending packages. carefully speci|64.8508|-147.703|64.8508|-147.703|
+1793|19|F|82504.56|1992-07-12|4-NOT SPECIFIED|Clerk#000000291|0|regular packages cajole. blithely special packages according to the final d|64.841|-147.72|64.841|-147.72|
+1794|140|O|179462.21|1997-09-28|1-URGENT|Clerk#000000686|0|ally silent pinto beans. regular package|64.8375|-147.721|64.8375|-147.721|
+1795|94|F|146849.33|1994-03-19|2-HIGH|Clerk#000000815|0| quickly final packages! blithely dogged accounts c|64.849|-147.813|64.849|-147.813|
+1796|47|F|33755.47|1992-11-21|2-HIGH|Clerk#000000245|0|eans use furiously around th|55.3801|-131.682|55.3801|-131.682|
+1797|125|O|51494.47|1996-05-07|3-MEDIUM|Clerk#000000508|0|quiet platelets haggle since the quickly ironic instructi|55.3801|-131.682|55.3801|-131.682|
+1798|52|O|46393.97|1997-07-28|1-URGENT|Clerk#000000741|0|al foxes are blithe|55.3603|-131.702|55.3603|-131.702|
+1799|61|F|46815.93|1994-03-07|4-NOT SPECIFIED|Clerk#000000339|0|ns sleep furiously final waters. blithely regular instructions h|55.7511|-132.865|55.7511|-132.865|
+1824|49|F|81351.53|1994-05-05|1-URGENT|Clerk#000000972|0|e blithely fluffily|55.7511|-132.865|55.7511|-132.865|
+1825|148|F|150582.77|1993-12-05|3-MEDIUM|Clerk#000000345|0|ironic, final accou|60.3311|-151.284|60.3311|-151.284|
+1826|82|F|124719.97|1992-04-16|4-NOT SPECIFIED|Clerk#000000718|0|the even asymptotes dazzle fluffily slyly regular asymptotes. final, unu|60.3311|-151.284|60.3311|-151.284|
+1827|106|O|210113.88|1996-06-22|4-NOT SPECIFIED|Clerk#000000369|0|luffily even requests haggle sly|60.3311|-151.284|60.3311|-151.284|
+1828|32|F|137369.50|1994-04-18|3-MEDIUM|Clerk#000000840|0|y quickly bold packag|60.4341|-151.283|60.4341|-151.283|
+1829|112|F|127532.20|1994-05-08|2-HIGH|Clerk#000000537|0| accounts wake above the furiously unusual requests. pending package|60.3311|-151.284|60.3311|-151.284|
+1830|133|F|85122.24|1995-02-23|1-URGENT|Clerk#000000045|0|according to the even,|60.3311|-151.284|60.3311|-151.284|
+1831|71|F|58032.77|1993-12-02|1-URGENT|Clerk#000000854|0| accounts. carefully even accounts boost furiously. regular ideas engage. |60.3311|-151.284|60.3311|-151.284|
+1856|106|F|189361.42|1992-03-20|4-NOT SPECIFIED|Clerk#000000952|0|. special pinto beans run acr|60.3311|-151.284|60.3311|-151.284|
+1857|133|F|102793.59|1993-01-13|2-HIGH|Clerk#000000083|0|hely final ideas slee|60.3311|-151.284|60.3311|-151.284|
+1858|143|O|30457.91|1997-12-13|1-URGENT|Clerk#000000389|0|thely. slyly final deposits sleep|60.4311|-151.286|60.4311|-151.286|
+1859|61|O|105094.09|1997-04-11|4-NOT SPECIFIED|Clerk#000000949|0| the foxes. bravely special excuses nag carefully special r|60.3311|-151.284|60.3311|-151.284|
+1860|10|O|9103.40|1996-04-04|3-MEDIUM|Clerk#000000556|0|osits. quickly bold deposits according to |60.3311|-151.284|60.3311|-151.284|
+1861|70|F|95063.41|1994-01-03|3-MEDIUM|Clerk#000000847|0|r the fluffily close sauternes. furio|60.3311|-151.284|60.3311|-151.284|
+1862|34|O|97981.06|1998-02-24|5-LOW|Clerk#000000348|0|ts snooze ironically abou|60.3311|-151.284|60.3311|-151.284|
+1863|74|F|96359.65|1993-09-23|4-NOT SPECIFIED|Clerk#000000658|0|old sentiments. careful, |60.3191|-151.296|60.3191|-151.296|
+1888|121|F|224724.11|1993-10-31|4-NOT SPECIFIED|Clerk#000000659|0|olites. pinto beans cajole. regular deposits affix. slyly regular|60.3311|-151.284|60.3311|-151.284|
+1889|25|O|96431.77|1997-03-16|1-URGENT|Clerk#000000854|0|p around the regular notornis. unusual deposits|60.3311|-151.284|60.3311|-151.284|
+1890|10|O|202364.58|1996-12-18|4-NOT SPECIFIED|Clerk#000000627|0|romise final, regular deposits. regular fox|60.3311|-151.284|60.3311|-151.284|
+1891|61|F|76848.96|1994-12-15|5-LOW|Clerk#000000495|0|unusual foxes sleep regular deposits. requests wake special pac|60.5563|-151.241|60.5563|-151.241|
+1892|25|F|133273.64|1994-03-26|5-LOW|Clerk#000000733|0|sts. slyly regular dependencies use slyly. ironic, spec|60.6331|-151.163|60.6331|-151.163|
+1893|125|O|116792.13|1997-10-30|2-HIGH|Clerk#000000111|0|olites. silent, special deposits eat slyly quickly express packages; hockey p|60.6331|-151.163|60.6331|-151.163|
+1894|76|F|44387.23|1992-03-30|1-URGENT|Clerk#000000626|0|e furiously. furiously even accounts are slyly final accounts. closely speci|60.6331|-151.163|60.6331|-151.163|
+1895|7|F|44429.81|1994-05-30|3-MEDIUM|Clerk#000000878|0|ress accounts. bold accounts cajole. slyly final pinto beans poach regul|60.6331|-151.163|60.6331|-151.163|
+1920|110|O|119605.91|1998-06-24|5-LOW|Clerk#000000018|0|hely; furiously regular excuses|60.5551|-151.245|60.5551|-151.245|
+1921|88|F|57584.12|1994-01-18|3-MEDIUM|Clerk#000000293|0|counts. slyly quiet requests along the ruthlessly regular accounts are |60.6331|-151.163|60.6331|-151.163|
+1922|56|O|11575.77|1996-07-13|3-MEDIUM|Clerk#000000984|0|side of the blithely final re|60.5506|-151.141|60.5506|-151.141|
+1923|136|O|171128.10|1997-07-07|1-URGENT|Clerk#000000471|0| express dolphins. |60.5681|-151.281|60.5681|-151.281|
+1924|76|O|169756.19|1996-09-07|4-NOT SPECIFIED|Clerk#000000823|0| of the ironic accounts. instructions near the final instr|60.5465|-151.147|60.5465|-151.147|
+1925|17|F|146382.71|1992-03-05|1-URGENT|Clerk#000000986|0|e slyly regular deposits. furiously |60.6331|-151.163|60.6331|-151.163|
+1926|94|O|100035.03|1996-01-31|2-HIGH|Clerk#000000568|0|cajole. even warhorses sleep carefully. |60.5578|-151.116|60.5578|-151.116|
+1927|140|O|23327.88|1995-09-30|3-MEDIUM|Clerk#000000616|0|riously special packages. permanent pearls wake furiously. even packages alo|61.6182|-149.385|61.6182|-149.385|
+1952|67|F|12896.25|1994-03-16|2-HIGH|Clerk#000000254|0| silent accounts boost |61.6141|-149.457|61.6141|-149.457|
+1953|149|F|57213.18|1993-11-30|3-MEDIUM|Clerk#000000891|0| fluffily along the quickly even packages. |61.5765|-149.407|61.5765|-149.407|
+1954|56|O|158853.63|1997-05-31|4-NOT SPECIFIED|Clerk#000000104|0| unusual excuses cajole according to the blithely regular theodolites.|61.6091|-149.77|61.6091|-149.77|
+1955|13|F|103085.13|1992-04-20|1-URGENT|Clerk#000000792|0|ly special ideas. sometimes final |61.5821|-149.438|61.5821|-149.438|
+1956|127|F|88704.26|1992-09-20|4-NOT SPECIFIED|Clerk#000000600|0|ironic ideas are silent ideas. furiously final deposits sleep slyly carefu|61.6183|-149.373|61.6183|-149.373|
+1957|31|O|77482.87|1998-07-21|2-HIGH|Clerk#000000639|0|nding excuses about the |61.6131|-149.403|61.6131|-149.403|
+1958|53|O|176294.34|1995-09-22|5-LOW|Clerk#000000343|0| haggle blithely. flu|61.6352|-149.265|61.6352|-149.265|
+1959|43|O|62277.18|1997-01-13|4-NOT SPECIFIED|Clerk#000000631|0| cajole about the blithely express requests. even excuses mold bl|61.5751|-149.645|61.5751|-149.645|
+1984|52|O|79230.47|1998-04-01|1-URGENT|Clerk#000000416|0| slyly special instructions. unusual foxes use packages. carefully regular req|61.6168|-149.374|61.6168|-149.374|
+1985|7|F|171522.54|1994-09-02|4-NOT SPECIFIED|Clerk#000000741|0|slyly slyly even pains. slyly reg|61.5939|-149.43|61.5939|-149.43|
+1986|149|F|34269.96|1994-05-05|2-HIGH|Clerk#000000609|0|across the theodolites. quick|61.5792|-149.495|61.5792|-149.495|
+1987|100|F|6406.29|1994-04-30|2-HIGH|Clerk#000000652|0|gular platelets alongside |61.6141|-149.457|61.6141|-149.457|
+1988|109|O|117132.72|1995-10-06|4-NOT SPECIFIED|Clerk#000000011|0|ly ironic dolphins serve quickly busy accounts. bu|61.5829|-149.448|61.5829|-149.448|
+1989|118|F|39263.28|1994-03-16|4-NOT SPECIFIED|Clerk#000000747|0|ely bold pinto beans ha|61.5938|-149.387|61.5938|-149.387|
+1990|119|F|48781.39|1994-12-16|2-HIGH|Clerk#000000114|0|e bold patterns. always regul|61.5849|-149.38|61.5849|-149.38|
+1991|19|F|139854.41|1992-09-07|4-NOT SPECIFIED|Clerk#000000854|0|ing accounts can haggle at the carefully final Tiresias-- pending, regular|61.5729|-149.389|61.5729|-149.389|
+2016|8|O|24347.36|1996-08-16|3-MEDIUM|Clerk#000000641|0|the carefully ironic foxes. requests nag bold, r|61.5823|-149.462|61.5823|-149.462|
+2017|101|O|70529.27|1998-05-13|3-MEDIUM|Clerk#000000427|0|nusual requests. blit|61.57|-149.331|61.57|-149.331|
+2018|19|P|25007.95|1995-04-05|4-NOT SPECIFIED|Clerk#000000920|0|gular accounts wake fur|61.5821|-149.438|61.5821|-149.438|
+2019|136|F|43789.14|1992-10-23|1-URGENT|Clerk#000000565|0| furiously bold packages. fluffily fi|61.6141|-149.457|61.6141|-149.457|
+2020|73|F|136162.13|1993-06-21|3-MEDIUM|Clerk#000000192|0|es. furiously regular packages above the furiously special theodolites are a|61.6115|-149.331|61.6115|-149.331|
+2021|70|O|27016.74|1995-07-15|1-URGENT|Clerk#000000155|0|ong the furiously regular requests. unusual deposits wake fluffily inside|61.6091|-149.77|61.6091|-149.77|
+2022|62|F|206742.11|1992-03-15|1-URGENT|Clerk#000000268|0| dependencies sleep fluffily even, ironic deposits. express, silen|61.6141|-149.457|61.6141|-149.457|
+2023|118|F|144123.37|1992-05-06|5-LOW|Clerk#000000137|0|ular courts engage according to the|61.5826|-149.427|61.5826|-149.427|
+2048|17|F|33401.77|1993-11-15|1-URGENT|Clerk#000000934|0|s cajole after the blithely final accounts. f|61.5976|-149.366|61.5976|-149.366|
+2049|31|O|153048.74|1995-12-07|2-HIGH|Clerk#000000859|0|ly regular requests thrash blithely about the fluffily even theodolites. r|61.5976|-149.366|61.5976|-149.366|
+2050|28|F|208517.98|1994-06-02|4-NOT SPECIFIED|Clerk#000000821|0|d accounts against the furiously regular packages use bli|61.5531|-149.651|61.5531|-149.651|
+2051|40|O|87988.34|1996-03-18|4-NOT SPECIFIED|Clerk#000000333|0|ctions sleep blithely. blithely regu|61.5531|-149.651|61.5531|-149.651|
+2052|91|F|141822.19|1992-04-13|2-HIGH|Clerk#000000767|0| requests sleep around the even, even courts. ironic theodolites affix furious|61.5883|-149.456|61.5883|-149.456|
+2053|142|F|125125.57|1995-02-07|1-URGENT|Clerk#000000717|0|ar requests: blithely sly accounts boost carefully across t|61.6249|-149.435|61.6249|-149.435|
+2054|41|F|144335.16|1992-06-08|4-NOT SPECIFIED|Clerk#000000103|0|l requests affix carefully about the furiously special|61.6141|-149.457|61.6141|-149.457|
+2055|97|F|57092.26|1993-09-04|1-URGENT|Clerk#000000067|0|. warhorses affix slyly blithely express instructions? fur|61.5709|-149.452|61.5709|-149.452|
+2080|95|F|45767.69|1993-06-18|5-LOW|Clerk#000000190|0|ironic, pending theodolites are carefully about the quickly regular theodolite|61.6651|-149.465|61.6651|-149.465|
+2081|121|O|145654.97|1997-07-05|2-HIGH|Clerk#000000136|0|ong the regular theo|61.5841|-149.441|61.5841|-149.441|
+2082|49|F|46753.63|1995-01-10|2-HIGH|Clerk#000000354|0|cial accounts. ironic, express dolphins nod slyly sometimes final reques|61.1571|-149.883|61.1571|-149.883|
+2083|101|F|31795.52|1993-07-14|3-MEDIUM|Clerk#000000361|0|al patterns. bold, final foxes nag bravely about the furiously express|61.2198|-149.733|61.2198|-149.733|
+2084|80|F|190652.53|1993-03-17|2-HIGH|Clerk#000000048|0|zle furiously final, careful packages. slyly ironic ideas amo|61.1863|-149.976|61.1863|-149.976|
+2085|49|F|45311.07|1993-11-21|3-MEDIUM|Clerk#000000818|0|ress, express ideas haggle|61.2161|-149.876|61.2161|-149.876|
+2086|142|F|188985.18|1994-10-19|1-URGENT|Clerk#000000046|0| permanently regular|61.2031|-149.749|61.2031|-149.749|
+2087|50|O|53581.41|1998-01-31|2-HIGH|Clerk#000000626|0|e always regular packages nod against the furiously spec|61.1644|-149.897|61.1644|-149.897|
+2112|64|O|17986.15|1997-02-05|2-HIGH|Clerk#000000351|0|against the slyly even id|61.1834|-149.866|61.1834|-149.866|
+2113|32|O|65678.21|1997-11-08|2-HIGH|Clerk#000000527|0|slyly regular instruct|61.1731|-149.889|61.1731|-149.889|
+2114|79|F|106446.02|1995-01-16|5-LOW|Clerk#000000751|0|r, unusual accounts haggle across the busy platelets. carefully |61.1089|-149.854|61.1089|-149.854|
+2115|106|O|134814.65|1998-05-23|4-NOT SPECIFIED|Clerk#000000101|0|odolites boost. carefully regular excuses cajole. quickly ironic pinto be|61.1951|-149.916|61.1951|-149.916|
+2116|23|F|60887.90|1994-08-26|1-URGENT|Clerk#000000197|0|efully after the asymptotes. furiously sp|61.2157|-149.821|61.2157|-149.821|
+2117|22|O|145713.03|1997-04-26|2-HIGH|Clerk#000000887|0|ely even dependencies. regular foxes use blithely.|61.1372|-149.954|61.1372|-149.954|
+2118|134|O|38974.67|1996-10-09|1-URGENT|Clerk#000000196|0|ial requests wake carefully special packages. f|61.1955|-149.737|61.1955|-149.737|
+2119|64|O|34632.57|1996-08-20|2-HIGH|Clerk#000000434|0|uickly pending escapades. fluffily ir|61.1444|-149.867|61.1444|-149.867|
+2144|136|F|119917.28|1994-03-29|3-MEDIUM|Clerk#000000546|0|t. carefully quick requests across the deposits wake regu|61.2178|-149.882|61.2178|-149.882|
+2145|134|F|18885.35|1992-10-03|1-URGENT|Clerk#000000886|0|sts would snooze blithely alongside of th|61.1824|-149.849|61.1824|-149.849|
+2146|118|F|179686.07|1992-09-14|4-NOT SPECIFIED|Clerk#000000476|0|ven packages. dependencies wake slyl|61.2161|-149.876|61.2161|-149.876|
+2147|100|F|91513.79|1992-09-06|4-NOT SPECIFIED|Clerk#000000424|0| haggle carefully furiously final foxes. pending escapades thrash. bold theod|61.2022|-149.84|61.2022|-149.84|
+2148|130|F|19612.03|1995-04-19|4-NOT SPECIFIED|Clerk#000000517|0|ross the furiously unusual theodolites. always expre|61.2099|-149.762|61.2099|-149.762|
+2149|101|F|105145.40|1993-03-13|5-LOW|Clerk#000000555|0|nusual accounts nag furiously special reques|61.1951|-149.84|61.1951|-149.84|
+2150|82|F|166961.06|1994-06-03|3-MEDIUM|Clerk#000000154|0|ect slyly against the even, final packages. quickly regular pinto beans wake c|61.1069|-149.859|61.1069|-149.859|
+2151|58|O|124608.69|1996-11-11|3-MEDIUM|Clerk#000000996|0|c requests. ironic platelets cajole across the quickly fluffy deposits.|61.1635|-149.881|61.1635|-149.881|
+2176|104|F|87248.17|1992-11-10|1-URGENT|Clerk#000000195|0|s haggle regularly accor|61.1201|-149.89|61.1201|-149.89|
+2177|136|O|183493.42|1997-01-20|3-MEDIUM|Clerk#000000161|0|ove the blithely unusual packages cajole carefully fluffily special request|61.1902|-149.908|61.1902|-149.908|
+2178|8|O|79594.68|1996-12-12|3-MEDIUM|Clerk#000000656|0|thely according to the instructions. furious|61.2104|-149.857|61.2104|-149.857|
+2179|41|O|77487.09|1996-09-07|2-HIGH|Clerk#000000935|0|ounts alongside of the furiously unusual braids cajol|61.1771|-149.97|61.1771|-149.97|
+2180|76|O|208481.57|1996-09-14|4-NOT SPECIFIED|Clerk#000000650|0|xpress, unusual pains. furiously ironic excu|61.1859|-149.976|61.1859|-149.976|
+2181|76|O|100954.64|1995-09-13|3-MEDIUM|Clerk#000000814|0|y against the ironic, even|61.2171|-149.9|61.2171|-149.9|
+2182|23|F|116003.11|1994-04-05|2-HIGH|Clerk#000000071|0|ccounts. quickly bold deposits across the excuses sl|61.1162|-149.755|61.1162|-149.755|
+2183|113|O|49841.12|1996-06-22|1-URGENT|Clerk#000000287|0| among the express, ironic packages. slyly ironic platelets integrat|61.1381|-149.844|61.1381|-149.844|
+2208|68|P|245388.06|1995-05-01|4-NOT SPECIFIED|Clerk#000000900|0|symptotes wake slyly blithely unusual packages.|61.1775|-149.941|61.1775|-149.941|
+2209|91|F|129086.93|1992-07-10|2-HIGH|Clerk#000000056|0|er above the slyly silent requests. furiously reg|61.1938|-149.878|61.1938|-149.878|
+2210|32|F|31689.46|1992-01-16|2-HIGH|Clerk#000000941|0| believe carefully quickly express pinto beans. deposi|61.1571|-149.883|61.1571|-149.883|
+2211|92|F|140031.23|1994-06-30|2-HIGH|Clerk#000000464|0|ffily bold courts e|61.1541|-149.958|61.1541|-149.958|
+2212|118|F|17231.05|1994-03-23|3-MEDIUM|Clerk#000000954|0|structions above the unusual requests use fur|61.135|-149.88|61.135|-149.88|
+2213|122|F|146136.10|1993-01-15|4-NOT SPECIFIED|Clerk#000000598|0|osits are carefully reg|61.1101|-149.857|61.1101|-149.857|
+2214|115|O|150345.63|1998-05-05|3-MEDIUM|Clerk#000000253|0|packages. fluffily even accounts haggle blithely. carefully ironic depen|61.1101|-149.857|61.1101|-149.857|
+2215|40|O|108239.46|1996-06-16|4-NOT SPECIFIED|Clerk#000000817|0|le final, final foxes. quickly regular gifts are carefully deposit|61.1101|-149.857|61.1101|-149.857|
+2240|56|F|174090.30|1992-03-06|4-NOT SPECIFIED|Clerk#000000622|0|accounts against the slyly express foxes are after the slyly regular |61.1101|-149.857|61.1101|-149.857|
+2241|103|F|165219.08|1993-05-11|1-URGENT|Clerk#000000081|0|y about the silent excuses. furiously ironic instructions along the sil|61.1101|-149.857|61.1101|-149.857|
+2242|82|O|15082.82|1997-07-20|4-NOT SPECIFIED|Clerk#000000360|0| pending multipliers. carefully express asymptotes use quickl|61.1101|-149.857|61.1101|-149.857|
+2243|49|O|10451.97|1995-06-10|2-HIGH|Clerk#000000813|0|ously regular deposits integrate s|61.1101|-149.857|61.1101|-149.857|
+2244|127|F|21207.08|1993-01-09|1-URGENT|Clerk#000001000|0|ckages. ironic, ironic accounts haggle blithely express excuses. |61.1101|-149.857|61.1101|-149.857|
+2245|58|F|150585.73|1993-04-28|3-MEDIUM|Clerk#000000528|0|ake carefully. braids haggle slyly quickly b|61.1101|-149.857|61.1101|-149.857|
+2246|113|O|85755.84|1996-05-27|4-NOT SPECIFIED|Clerk#000000739|0| final gifts sleep |61.1101|-149.857|61.1101|-149.857|
+2247|95|F|13491.31|1992-08-02|4-NOT SPECIFIED|Clerk#000000947|0|furiously regular packages. final brai|61.1101|-149.857|61.1101|-149.857|
+2272|139|F|127934.71|1993-04-13|2-HIGH|Clerk#000000449|0|s. bold, ironic pinto beans wake. silently specia|61.1101|-149.857|61.1101|-149.857|
+2273|136|O|142291.79|1996-12-14|5-LOW|Clerk#000000155|0|uickly express foxes haggle quickly against|61.1101|-149.857|61.1101|-149.857|
+2274|104|F|58273.89|1993-09-04|4-NOT SPECIFIED|Clerk#000000258|0|nstructions try to hag|61.1101|-149.857|61.1101|-149.857|
+2275|149|F|37398.90|1992-10-22|4-NOT SPECIFIED|Clerk#000000206|0| furiously furious platelets. slyly final packa|61.1101|-149.857|61.1101|-149.857|
+2276|43|O|141159.63|1996-04-29|4-NOT SPECIFIED|Clerk#000000821|0|ecial requests. fox|61.1101|-149.857|61.1101|-149.857|
+2277|89|F|79270.23|1995-01-02|4-NOT SPECIFIED|Clerk#000000385|0|accounts cajole. even i|61.1101|-149.857|61.1101|-149.857|
+2278|142|O|101878.46|1998-04-25|3-MEDIUM|Clerk#000000186|0|r pinto beans integrate after the carefully even deposits. blit|61.1101|-149.857|61.1101|-149.857|
+2279|80|F|142322.33|1993-02-23|3-MEDIUM|Clerk#000000898|0|de of the quickly unusual instructio|61.2141|-149.864|61.2141|-149.864|
+2304|46|F|93769.28|1994-01-07|4-NOT SPECIFIED|Clerk#000000415|0|onic platelets. ironic packages haggle. packages nag doggedly according to|61.2171|-149.9|61.2171|-149.9|
+2305|43|F|122964.66|1993-01-26|2-HIGH|Clerk#000000440|0|ove the furiously even acco|61.2171|-149.9|61.2171|-149.9|
+2306|28|O|244704.23|1995-07-26|2-HIGH|Clerk#000000975|0| wake furiously requests. permanent requests affix. final packages caj|61.2171|-149.9|61.2171|-149.9|
+2307|106|F|59417.76|1993-06-29|5-LOW|Clerk#000000952|0|furiously even asymptotes? carefully regular accounts|61.2171|-149.9|61.2171|-149.9|
+2308|25|F|58546.02|1992-10-25|4-NOT SPECIFIED|Clerk#000000609|0|ts. slyly final depo|61.2171|-149.9|61.2171|-149.9|
+2309|100|O|146933.07|1995-09-04|5-LOW|Clerk#000000803|0|he carefully pending packages. fluffily stealthy foxes engage carefully|61.2171|-149.9|61.2171|-149.9|
+2310|31|O|82928.12|1996-09-20|5-LOW|Clerk#000000917|0|wake carefully. unusual instructions nag ironic, regular excuse|61.2171|-149.9|61.2171|-149.9|
+2311|73|P|153233.93|1995-05-02|2-HIGH|Clerk#000000761|0|ly pending asymptotes-- furiously bold excus|61.2171|-149.9|61.2171|-149.9|
+2336|142|O|22294.51|1996-01-07|4-NOT SPECIFIED|Clerk#000000902|0|c, final excuses sleep furiously among the even theodolites. f|61.2171|-149.9|61.2171|-149.9|
+2337|142|O|45704.96|1997-06-18|4-NOT SPECIFIED|Clerk#000000754|0| quickly. final accounts haggle. carefully final acco|61.2171|-149.9|61.2171|-149.9|
+2338|140|O|28155.92|1997-09-15|2-HIGH|Clerk#000000951|0|riously final dugouts. final, ironic packages wake express, ironic id|61.2171|-149.9|61.2171|-149.9|
+2339|109|F|63470.78|1993-12-15|5-LOW|Clerk#000000847|0| against the regular |61.2171|-149.9|61.2171|-149.9|
+2340|65|O|30778.78|1996-01-12|1-URGENT|Clerk#000000964|0|ter the deposits sleep according to the slyly regular packages. carefully |61.2171|-149.9|61.2171|-149.9|
+2341|82|F|55950.21|1993-05-30|5-LOW|Clerk#000000443|0|sts-- blithely bold dolphins through the deposits nag blithely carefully re|61.2171|-149.9|61.2171|-149.9|
+2342|37|O|104038.78|1996-06-09|1-URGENT|Clerk#000000615|0|oost carefully across the regular accounts. blithely final d|61.2171|-149.9|61.2171|-149.9|
+2343|73|O|85381.00|1995-08-21|3-MEDIUM|Clerk#000000170|0|fluffily over the slyly special deposits. quickl|64.8487|-147.704|64.8487|-147.704|
+2368|13|F|101240.96|1993-08-20|1-URGENT|Clerk#000000830|0|t the bold instructions. carefully unusual |64.8486|-147.705|64.8486|-147.705|
+2369|110|O|73517.91|1996-12-24|2-HIGH|Clerk#000000752|0|iously even requests are dogged, express |64.8087|-147.71|64.8087|-147.71|
+2370|142|F|73924.21|1994-01-17|1-URGENT|Clerk#000000231|0|lyly final packages. quickly final deposits haggl|64.8363|-147.758|64.8363|-147.758|
+2371|19|O|193857.67|1998-01-07|1-URGENT|Clerk#000000028|0|ckages haggle at th|64.8476|-147.704|64.8476|-147.704|
+2372|31|O|104927.66|1997-11-21|5-LOW|Clerk#000000342|0|s: deposits haggle along the final ideas. careful|64.8302|-147.744|64.8302|-147.744|
+2373|28|F|55211.04|1994-03-12|4-NOT SPECIFIED|Clerk#000000306|0| even, special courts grow quickly. pending,|64.8476|-147.812|64.8476|-147.812|
+2374|4|F|115219.88|1993-10-29|4-NOT SPECIFIED|Clerk#000000081|0| blithely regular packages. blithely unusua|64.8144|-147.756|64.8144|-147.756|
+2375|5|O|106612.48|1996-11-20|3-MEDIUM|Clerk#000000197|0|unusual, pending theodolites cajole carefully |64.8183|-147.778|64.8183|-147.778|
+2400|37|O|92798.66|1998-07-25|5-LOW|Clerk#000000782|0|nusual courts nag against the carefully unusual pinto b|64.8494|-147.818|64.8494|-147.818|
+2401|148|O|88448.24|1997-07-29|4-NOT SPECIFIED|Clerk#000000531|0|ully unusual instructions boost carefully silently regular requests. |64.849|-147.822|64.849|-147.822|
+2402|67|O|70403.62|1996-09-06|4-NOT SPECIFIED|Clerk#000000162|0|slyly final sheaves sleep slyly. q|64.8367|-147.716|64.8367|-147.716|
+2403|55|O|111020.79|1998-04-11|3-MEDIUM|Clerk#000000820|0|furiously regular deposits use. furiously unusual accounts wake along the |64.8127|-147.772|64.8127|-147.772|
+2404|77|O|109077.69|1997-03-13|4-NOT SPECIFIED|Clerk#000000409|0|deposits breach furiously. ironic foxes haggle carefully bold packag|64.8143|-147.751|64.8143|-147.751|
+2405|73|O|115929.14|1996-12-23|3-MEDIUM|Clerk#000000535|0|ular, regular asympto|64.842|-147.721|64.842|-147.721|
+2406|7|O|182516.77|1996-10-28|5-LOW|Clerk#000000561|0|blithely regular accounts u|64.8403|-147.714|64.8403|-147.714|
+2407|55|O|112843.52|1998-06-19|2-HIGH|Clerk#000000068|0|uests affix slyly among the slyly regular depos|64.8371|-147.881|64.8371|-147.881|
+2432|103|O|62661.93|1996-07-13|1-URGENT|Clerk#000000115|0|re. slyly even deposits wake bra|64.8151|-147.707|64.8151|-147.707|
+2433|31|F|147071.86|1994-08-22|4-NOT SPECIFIED|Clerk#000000324|0|ess patterns are slyly. packages haggle carefu|64.8151|-147.707|64.8151|-147.707|
+2434|25|O|123956.25|1997-04-27|3-MEDIUM|Clerk#000000190|0|s. quickly ironic dolphins impress final deposits. blithel|64.8541|-147.81|64.8541|-147.81|
+2435|73|F|122490.66|1993-02-21|5-LOW|Clerk#000000112|0|es are carefully along the carefully final instructions. pe|64.8878|-147.496|64.8878|-147.496|
+2436|125|O|73990.08|1995-09-11|4-NOT SPECIFIED|Clerk#000000549|0|arefully. blithely bold deposits affix special accounts. final foxes nag. spe|64.8299|-147.728|64.8299|-147.728|
+2437|85|F|143411.69|1993-04-21|4-NOT SPECIFIED|Clerk#000000578|0|. theodolites wake slyly-- ironic, pending platelets above the carefully exp|64.8132|-147.762|64.8132|-147.762|
+2438|13|F|214494.39|1993-07-15|2-HIGH|Clerk#000000744|0|the final, regular warhorses. regularly |64.8372|-147.713|64.8372|-147.713|
+2439|55|O|41811.12|1997-03-15|2-HIGH|Clerk#000000819|0|lithely after the car|64.7927|-148.036|64.7927|-148.036|
+2464|145|O|30495.65|1997-11-23|5-LOW|Clerk#000000633|0|le about the instructions. courts wake carefully even|64.8717|-147.819|64.8717|-147.819|
+2465|34|O|180737.75|1995-06-24|1-URGENT|Clerk#000000078|0|al pinto beans. final, bold packages wake quickly|64.8527|-147.686|64.8527|-147.686|
+2466|19|F|161625.50|1994-03-06|1-URGENT|Clerk#000000424|0|c pinto beans. express deposits wake quickly. even, final courts nag. package|64.8371|-147.811|64.8371|-147.811|
+2467|35|O|7231.91|1995-07-16|4-NOT SPECIFIED|Clerk#000000914|0|pades sleep furiously. sometimes regular packages again|64.846|-147.705|64.846|-147.705|
+2468|112|O|160627.01|1997-06-09|4-NOT SPECIFIED|Clerk#000000260|0|ickly regular packages. slyly ruthless requests snooze quickly blithe|64.9064|-147.726|64.9064|-147.726|
+2469|124|O|192074.23|1996-11-26|5-LOW|Clerk#000000730|0| sleep closely regular instructions. furiously ironic instructi|64.9347|-147.56|64.9347|-147.56|
+2470|58|O|104966.33|1997-04-19|3-MEDIUM|Clerk#000000452|0|to the furiously final packages? pa|64.8861|-147.677|64.8861|-147.677|
+2471|89|O|34936.31|1998-03-12|4-NOT SPECIFIED|Clerk#000000860|0|carefully blithely regular pac|64.8302|-147.744|64.8302|-147.744|
+2496|136|F|140390.60|1994-01-09|2-HIGH|Clerk#000000142|0|slyly. pending instructions sleep. quic|60.6673|-151.311|60.6673|-151.311|
+2497|47|F|171326.48|1992-08-27|1-URGENT|Clerk#000000977|0|ily ironic pinto beans. furiously final platelets alongside of t|60.6997|-151.38|60.6997|-151.38|
+2498|97|F|45514.27|1993-11-08|5-LOW|Clerk#000000373|0|g the slyly special pinto beans. |60.5658|-151.244|60.5658|-151.244|
+2499|121|O|147243.86|1995-09-24|1-URGENT|Clerk#000000277|0|r the quickly bold foxes. bold instructi|60.6331|-151.163|60.6331|-151.163|
+2500|133|F|131122.82|1992-08-15|2-HIGH|Clerk#000000447|0|integrate slyly pending deposits. furiously ironic accounts across the s|60.6331|-151.163|60.6331|-151.163|
+2501|67|O|79380.51|1997-05-25|5-LOW|Clerk#000000144|0|ickly special theodolite|60.6331|-151.163|60.6331|-151.163|
+2502|70|F|33470.40|1993-05-28|4-NOT SPECIFIED|Clerk#000000914|0|lyly: carefully pending ideas affix again|60.6201|-151.332|60.6201|-151.332|
+2503|7|F|183671.08|1993-06-20|3-MEDIUM|Clerk#000000294|0|ly even packages was. ironic, regular deposits unwind furiously across the p|60.5004|-151.276|60.5004|-151.276|
+2528|55|F|92069.62|1994-11-20|1-URGENT|Clerk#000000789|0|ular dependencies? regular frays kindle according to the blith|60.6331|-151.163|60.6331|-151.163|
+2529|136|O|4104.30|1996-08-20|2-HIGH|Clerk#000000511|0|posits across the silent instructions wake blithely across |60.6331|-151.163|60.6331|-151.163|
+2530|128|F|58853.11|1994-03-21|3-MEDIUM|Clerk#000000291|0|ular instructions about the quic|60.6901|-151.321|60.6901|-151.321|
+2531|44|O|143212.85|1996-05-06|4-NOT SPECIFIED|Clerk#000000095|0|even accounts. furiously ironic excuses sleep fluffily. carefully silen|60.6676|-151.29|60.6676|-151.29|
+2532|94|O|116093.49|1995-10-11|2-HIGH|Clerk#000000498|0|the blithely pending accounts. regular, regular excuses boost aro|60.6331|-151.163|60.6331|-151.163|
+2533|50|O|168495.03|1997-03-24|1-URGENT|Clerk#000000594|0|ecial instructions. spec|60.5632|-151.266|60.5632|-151.266|
+2534|76|O|202784.54|1996-07-17|3-MEDIUM|Clerk#000000332|0|packages cajole ironic requests. furiously regular|60.6331|-151.163|60.6331|-151.163|
+2535|121|F|67018.30|1993-05-25|5-LOW|Clerk#000000296|0|phins cajole beneath the fluffily express asymptotes. c|60.6331|-151.163|60.6331|-151.163|
+2560|131|F|153426.79|1992-09-05|1-URGENT|Clerk#000000538|0|atelets; quickly sly requests|60.6509|-151.342|60.6509|-151.342|
+2561|58|O|137473.58|1997-11-14|1-URGENT|Clerk#000000861|0|ual requests. unusual deposits cajole furiously pending, regular platelets. |60.5601|-151.107|60.5601|-151.107|
+2562|10|F|136360.37|1992-08-01|1-URGENT|Clerk#000000467|0|elets. pending dolphins promise slyly. bo|60.5123|-151.275|60.5123|-151.275|
+2563|62|F|168952.10|1993-11-19|4-NOT SPECIFIED|Clerk#000000150|0|sly even packages after the furio|60.6076|-151.325|60.6076|-151.325|
+2564|77|F|3967.47|1994-09-09|2-HIGH|Clerk#000000718|0|usly regular pinto beans. orbits wake carefully. slyly e|60.6331|-151.163|60.6331|-151.163|
+2565|56|O|204438.57|1998-02-28|3-MEDIUM|Clerk#000000032|0|x-ray blithely along|60.5175|-151.235|60.5175|-151.235|
+2566|86|F|89992.48|1992-10-10|3-MEDIUM|Clerk#000000414|0|ructions boost bold ideas. idly ironic accounts use according to th|60.5535|-151.108|60.5535|-151.108|
+2567|70|O|263411.29|1998-02-27|2-HIGH|Clerk#000000031|0|detect. furiously ironic requests|60.5614|-151.275|60.5614|-151.275|
+2592|101|F|8225.96|1993-03-05|4-NOT SPECIFIED|Clerk#000000524|0|ts nag fluffily. quickly stealthy theodolite|60.5647|-151.195|60.5647|-151.195|
+2593|92|F|134726.09|1993-09-04|2-HIGH|Clerk#000000468|0|r the carefully final|60.6331|-151.163|60.6331|-151.163|
+2594|79|F|94866.39|1992-12-17|1-URGENT|Clerk#000000550|0|ests. theodolites above the blithely even accounts detect furio|60.6331|-151.163|60.6331|-151.163|
+2595|74|O|173130.20|1995-12-14|4-NOT SPECIFIED|Clerk#000000222|0|arefully ironic requests nag carefully ideas. |60.6331|-151.163|60.6331|-151.163|
+2596|43|O|74940.13|1996-08-17|1-URGENT|Clerk#000000242|0|requests. ironic, bold theodolites wak|60.6331|-151.163|60.6331|-151.163|
+2597|104|F|21964.66|1993-02-04|2-HIGH|Clerk#000000757|0|iously ruthless exc|60.6331|-151.163|60.6331|-151.163|
+2598|112|O|84871.50|1996-03-05|3-MEDIUM|Clerk#000000391|0| ironic notornis according to the blithely final requests should |60.6678|-151.31|60.6678|-151.31|
+2599|149|O|62807.13|1996-11-07|2-HIGH|Clerk#000000722|0|ts. slyly regular theodolites wake sil|60.5003|-151.276|60.5003|-151.276|
+2624|52|O|27148.63|1996-11-28|5-LOW|Clerk#000000930|0|ic, regular packages|60.6331|-151.163|60.6331|-151.163|
+2625|40|F|39382.74|1992-10-14|4-NOT SPECIFIED|Clerk#000000386|0| final deposits. blithely ironic ideas |61.5855|-149.326|61.5855|-149.326|
+2626|139|O|84314.51|1995-09-08|4-NOT SPECIFIED|Clerk#000000289|0|gside of the carefully special packages are furiously after the slyly express |61.5979|-149.437|61.5979|-149.437|
+2627|149|F|26798.65|1992-03-24|3-MEDIUM|Clerk#000000181|0|s. silent, ruthless requests|61.6141|-149.457|61.6141|-149.457|
+2628|56|F|165655.99|1993-10-22|5-LOW|Clerk#000000836|0|ajole across the blithely careful accounts. blithely silent deposits sl|61.5799|-149.461|61.5799|-149.461|
+2629|139|O|96458.03|1998-04-06|5-LOW|Clerk#000000680|0|uches dazzle carefully even, express excuses. ac|61.5845|-149.337|61.5845|-149.337|
+2630|85|F|127132.51|1992-10-24|5-LOW|Clerk#000000712|0|inal theodolites. ironic instructions s|61.5351|-149.558|61.5351|-149.558|
+2631|37|F|63103.32|1993-09-24|5-LOW|Clerk#000000833|0| quickly unusual deposits doubt around |61.5811|-149.45|61.5811|-149.45|
+2656|77|F|105492.37|1993-05-04|1-URGENT|Clerk#000000307|0|elets. slyly final accou|61.5793|-149.442|61.5793|-149.442|
+2657|25|O|148176.06|1995-10-17|2-HIGH|Clerk#000000160|0| foxes-- slyly final dependencies around the slyly final theodo|61.5661|-149.313|61.5661|-149.313|
+2658|14|O|163834.46|1995-09-23|3-MEDIUM|Clerk#000000400|0|bout the slyly regular accounts. ironic, |61.6141|-149.457|61.6141|-149.457|
+2659|83|F|79785.52|1993-12-18|4-NOT SPECIFIED|Clerk#000000758|0|cross the pending requests maintain |61.5786|-149.332|61.5786|-149.332|
+2660|127|O|16922.51|1995-08-05|5-LOW|Clerk#000000480|0|ly finally regular deposits. ironic theodolites cajole|61.5811|-149.45|61.5811|-149.45|
+2661|74|O|106036.84|1997-01-04|3-MEDIUM|Clerk#000000217|0|al, regular pinto beans. silently final deposits should have t|61.5825|-149.429|61.5825|-149.429|
+2662|37|O|87689.88|1996-08-21|3-MEDIUM|Clerk#000000589|0|bold pinto beans above the slyly final accounts affix furiously deposits. pac|61.6141|-149.457|61.6141|-149.457|
+2663|95|O|35131.80|1995-09-06|1-URGENT|Clerk#000000950|0|ar requests. furiously final dolphins along the fluffily spe|61.5531|-149.651|61.5531|-149.651|
+2688|98|F|181077.36|1992-01-24|2-HIGH|Clerk#000000720|0|have to nag according to the pending theodolites. sly|61.5531|-149.651|61.5531|-149.651|
+2689|103|F|41552.78|1992-04-09|4-NOT SPECIFIED|Clerk#000000698|0|press pains wake. furiously express theodolites alongsid|61.5698|-149.62|61.5698|-149.62|
+2690|94|O|224674.27|1996-03-31|3-MEDIUM|Clerk#000000760|0|ravely even theodolites |61.6141|-149.457|61.6141|-149.457|
+2691|7|F|30137.17|1992-04-30|5-LOW|Clerk#000000439|0|es at the regular deposits sleep slyly by the fluffy requests. eve|61.5474|-149.458|61.5474|-149.458|
+2692|62|O|24265.24|1997-12-02|3-MEDIUM|Clerk#000000878|0|es. regular asymptotes cajole above t|61.5825|-149.429|61.5825|-149.429|
+2693|19|O|66158.13|1996-09-04|1-URGENT|Clerk#000000370|0|ndle never. blithely regular packages nag carefully enticing platelets. ca|61.5955|-149.423|61.5955|-149.423|
+2694|121|O|102807.59|1996-03-14|5-LOW|Clerk#000000722|0| requests. bold deposits above the theodol|61.5801|-149.461|61.5801|-149.461|
+2695|58|O|138584.20|1996-08-20|1-URGENT|Clerk#000000697|0|ven deposits around the quickly regular packa|61.5785|-149.415|61.5785|-149.415|
+2720|31|F|161307.05|1993-06-08|1-URGENT|Clerk#000000948|0|quickly. special asymptotes are fluffily ironi|61.6402|-149.34|61.6402|-149.34|
+2721|79|O|59180.25|1996-01-27|2-HIGH|Clerk#000000401|0| ideas eat even, unusual ideas. theodolites are carefully|61.583|-149.457|61.583|-149.457|
+2722|35|F|50328.84|1994-04-09|5-LOW|Clerk#000000638|0|rding to the carefully quick deposits. bli|61.5907|-149.295|61.5907|-149.295|
+2723|61|O|104759.25|1995-10-06|5-LOW|Clerk#000000836|0|nts must have to cajo|61.6141|-149.457|61.6141|-149.457|
+2724|137|F|116069.66|1994-09-14|2-HIGH|Clerk#000000217|0| sleep blithely. blithely idle |61.5933|-149.397|61.5933|-149.397|
+2725|89|F|75144.68|1994-05-21|4-NOT SPECIFIED|Clerk#000000835|0|ular deposits. spec|61.6091|-149.77|61.6091|-149.77|
+2726|7|F|47753.00|1992-11-27|5-LOW|Clerk#000000470|0| blithely even dinos sleep care|61.577|-149.411|61.577|-149.411|
+2727|74|O|3089.42|1998-04-19|4-NOT SPECIFIED|Clerk#000000879|0|sual theodolites cajole enticingly above the furiously fin|61.6078|-149.322|61.6078|-149.322|
+2752|59|F|187932.30|1993-11-19|2-HIGH|Clerk#000000648|0| carefully regular foxes are quickly quickl|61.6131|-149.397|61.6131|-149.397|
+2753|16|F|159720.39|1993-11-30|2-HIGH|Clerk#000000380|0|ending instructions. unusual deposits|61.6648|-149.372|61.6648|-149.372|
+2754|145|F|25985.52|1994-04-03|2-HIGH|Clerk#000000960|0|cies detect slyly. |61.5531|-149.651|61.5531|-149.651|
+2755|118|F|101202.18|1992-02-07|4-NOT SPECIFIED|Clerk#000000177|0|ously according to the sly foxes. blithely regular pinto bean|61.5811|-149.45|61.5811|-149.45|
+2756|118|F|142323.38|1994-04-18|1-URGENT|Clerk#000000537|0|arefully special warho|61.583|-149.457|61.583|-149.457|
+2757|76|O|89792.48|1995-07-20|2-HIGH|Clerk#000000216|0| regular requests subl|61.1955|-149.9|61.1955|-149.9|
+2758|43|O|36671.88|1998-07-12|5-LOW|Clerk#000000863|0|s cajole according to the carefully special |61.1844|-149.897|61.1844|-149.897|
+2759|116|F|89731.10|1993-11-25|4-NOT SPECIFIED|Clerk#000000071|0|ts. regular, pending pinto beans sleep ab|61.1901|-149.892|61.1901|-149.892|
+2784|95|O|106635.21|1998-01-07|1-URGENT|Clerk#000000540|0|g deposits alongside of the silent requests s|61.1444|-149.867|61.1444|-149.867|
+2785|148|O|132854.79|1995-07-21|2-HIGH|Clerk#000000098|0|iously pending packages sleep according to the blithely unusual foxe|61.1955|-149.9|61.1955|-149.9|
+2786|79|F|178254.66|1992-03-22|2-HIGH|Clerk#000000976|0|al platelets cajole blithely ironic requests. ironic re|61.1893|-149.887|61.1893|-149.887|
+2787|103|O|3726.14|1995-09-30|1-URGENT|Clerk#000000906|0|he ironic, regular |61.2174|-149.888|61.2174|-149.888|
+2788|124|F|17172.66|1994-09-22|1-URGENT|Clerk#000000641|0|nts wake across the fluffily bold accoun|61.2227|-149.842|61.2227|-149.842|
+2789|37|O|219123.27|1998-03-14|2-HIGH|Clerk#000000972|0|gular patterns boost. carefully even re|61.1263|-149.872|61.1263|-149.872|
+2790|25|F|177458.97|1994-08-19|2-HIGH|Clerk#000000679|0| the carefully express deposits sleep slyly |61.1138|-149.866|61.1138|-149.866|
+2791|121|F|156697.55|1994-10-10|2-HIGH|Clerk#000000662|0|as. slyly ironic accounts play furiously bl|61.2157|-149.821|61.2157|-149.821|
+2816|58|F|42225.53|1994-09-20|2-HIGH|Clerk#000000289|0|kages at the final deposits cajole furious foxes. quickly |61.2174|-149.888|61.2174|-149.888|
+2817|40|F|71453.85|1994-04-19|3-MEDIUM|Clerk#000000982|0|ic foxes haggle upon the daringly even pinto beans. slyly|61.1855|-149.868|61.1855|-149.868|
+2818|49|F|120086.84|1994-12-12|3-MEDIUM|Clerk#000000413|0|eep furiously special ideas. express |61.1951|-149.873|61.1951|-149.873|
+2819|103|F|66927.16|1994-05-05|1-URGENT|Clerk#000000769|0|ngside of the blithely ironic dolphins. furio|61.1444|-149.867|61.1444|-149.867|
+2820|19|F|143813.39|1994-05-20|3-MEDIUM|Clerk#000000807|0|equests are furiously. carefu|61.1883|-149.735|61.1883|-149.735|
+2821|118|F|36592.48|1993-08-09|3-MEDIUM|Clerk#000000323|0|ng requests. even instructions are quickly express, silent instructi|61.2161|-149.876|61.2161|-149.876|
+2822|79|F|40142.15|1993-07-26|2-HIGH|Clerk#000000510|0|furiously against the accounts. unusual accounts aft|61.2161|-149.876|61.2161|-149.876|
+2823|79|O|171894.45|1995-09-09|2-HIGH|Clerk#000000567|0|encies. carefully fluffy accounts m|61.1893|-149.888|61.1893|-149.888|
+2848|70|F|116258.53|1992-03-10|1-URGENT|Clerk#000000256|0|ly fluffy foxes sleep furiously across the slyly regu|61.2174|-149.888|61.2174|-149.888|
+2849|46|O|180054.29|1996-04-30|2-HIGH|Clerk#000000659|0|al packages are after the quickly bold requests. carefully special |61.1914|-149.886|61.1914|-149.886|
+2850|100|O|122969.79|1996-10-02|2-HIGH|Clerk#000000392|0|, regular deposits. furiously pending packages hinder carefully carefully u|61.1541|-149.958|61.1541|-149.958|
+2851|145|O|7859.36|1997-09-07|5-LOW|Clerk#000000566|0|Tiresias wake quickly quickly even|61.1259|-149.717|61.1259|-149.717|
+2852|91|F|99050.81|1993-01-16|1-URGENT|Clerk#000000740|0|ruthless deposits against the final instructions use quickly al|61.2193|-149.902|61.2193|-149.902|
+2853|94|F|103641.15|1994-05-05|2-HIGH|Clerk#000000878|0|the carefully even packages.|61.1879|-149.886|61.1879|-149.886|
+2854|139|F|153568.02|1994-06-27|1-URGENT|Clerk#000000010|0| furiously ironic tithes use furiously |61.1372|-149.912|61.1372|-149.912|
+2855|49|F|48419.58|1993-04-04|4-NOT SPECIFIED|Clerk#000000973|0| silent, regular packages sleep |61.1101|-149.857|61.1101|-149.857|
+2880|8|F|145761.99|1992-03-15|2-HIGH|Clerk#000000756|0|ves maintain doggedly spec|61.1791|-149.94|61.1791|-149.94|
+2881|100|F|45695.84|1992-05-10|5-LOW|Clerk#000000864|0|uriously. slyly express requests according to the silent dol|61.2031|-149.749|61.2031|-149.749|
+2882|121|O|172872.37|1995-08-22|2-HIGH|Clerk#000000891|0|pending deposits. carefully eve|61.1914|-149.877|61.1914|-149.877|
+2883|121|F|170360.27|1995-01-23|5-LOW|Clerk#000000180|0|uses. carefully ironic accounts lose fluffil|61.1944|-149.883|61.1944|-149.883|
+2884|92|O|71683.84|1997-10-12|3-MEDIUM|Clerk#000000780|0|efully express instructions sleep against|61.1923|-149.886|61.1923|-149.886|
+2885|7|F|146896.72|1992-09-19|4-NOT SPECIFIED|Clerk#000000280|0|ly sometimes special excuses. final requests are |61.2123|-149.854|61.2123|-149.854|
+2886|109|F|94527.23|1994-11-13|4-NOT SPECIFIED|Clerk#000000619|0|uctions. ironic packages sle|61.2161|-149.876|61.2161|-149.876|
+2887|109|O|28571.39|1997-05-26|5-LOW|Clerk#000000566|0|slyly even pinto beans. slyly bold epitaphs cajole blithely above t|61.2171|-149.9|61.2171|-149.9|
+2912|94|F|27727.52|1992-03-12|5-LOW|Clerk#000000186|0|jole blithely above the quickly regular packages. carefully regular pinto bean|61.1125|-149.861|61.1125|-149.861|
+2913|43|O|130702.19|1997-07-12|3-MEDIUM|Clerk#000000118|0|mptotes doubt furiously slyly regu|61.1419|-149.896|61.1419|-149.896|
+2914|109|F|60867.14|1993-03-03|3-MEDIUM|Clerk#000000543|0|he slyly regular theodolites are furiously sile|61.145|-149.878|61.145|-149.878|
+2915|94|F|96015.13|1994-03-31|5-LOW|Clerk#000000410|0|ld packages. bold deposits boost blithely. ironic, unusual theodoli|61.1044|-149.865|61.1044|-149.865|
+2916|8|O|20182.22|1995-12-27|2-HIGH|Clerk#000000681|0|ithely blithe deposits sleep beyond the|61.1444|-149.876|61.1444|-149.876|
+2917|91|O|100714.13|1997-12-09|4-NOT SPECIFIED|Clerk#000000061|0| special dugouts among the special deposi|61.1|-149.85|61.1|-149.85|
+2918|118|O|21760.09|1996-09-08|3-MEDIUM|Clerk#000000439|0|ular deposits across th|61.1105|-149.861|61.1105|-149.861|
+2919|53|F|137223.14|1993-12-10|2-HIGH|Clerk#000000209|0|es. pearls wake quietly slyly ironic instructions--|61.1286|-149.957|61.1286|-149.957|
+2944|14|O|146581.14|1997-09-24|4-NOT SPECIFIED|Clerk#000000740|0|deas. permanently special foxes haggle carefully ab|61.1201|-149.89|61.1201|-149.89|
+2945|29|O|223507.72|1996-01-03|2-HIGH|Clerk#000000499|0|ons are carefully toward the permanent, bold pinto beans. regu|61.112|-149.871|61.112|-149.871|
+2946|125|O|102226.59|1996-02-05|5-LOW|Clerk#000000329|0|g instructions about the regular accounts sleep carefully along the pen|61.1427|-149.864|61.1427|-149.864|
+2947|70|P|43360.95|1995-04-26|1-URGENT|Clerk#000000464|0|ronic accounts. accounts run furiously d|61.1212|-149.947|61.1212|-149.947|
+2948|44|F|100758.71|1994-08-23|5-LOW|Clerk#000000701|0| deposits according to the blithely pending |61.1228|-149.939|61.1228|-149.939|
+2949|137|F|94231.71|1994-04-12|2-HIGH|Clerk#000000184|0|y ironic accounts use. quickly blithe accou|61.1093|-149.871|61.1093|-149.871|
+2950|136|O|183620.33|1997-07-06|1-URGENT|Clerk#000000833|0| dolphins around the furiously |61.145|-149.878|61.145|-149.878|
+2951|74|O|125509.17|1996-02-06|2-HIGH|Clerk#000000680|0|gular deposits above the finally regular ideas integrate idly stealthil|61.1191|-149.871|61.1191|-149.871|
+2976|29|F|145768.47|1993-12-10|4-NOT SPECIFIED|Clerk#000000159|0|. furiously ironic asymptotes haggle ruthlessly silently regular r|61.1003|-149.856|61.1003|-149.856|
+2977|73|O|25170.88|1996-08-27|3-MEDIUM|Clerk#000000252|0|quickly special platelets are furio|61.1113|-149.872|61.1113|-149.872|
+2978|44|P|139542.14|1995-05-03|1-URGENT|Clerk#000000135|0|d. even platelets are. ironic dependencies cajole slow, e|61.1084|-149.861|61.1084|-149.861|
+2979|133|O|116789.98|1996-03-23|3-MEDIUM|Clerk#000000820|0|even, ironic foxes sleep along|61.144|-149.878|61.144|-149.878|
+2980|4|O|187514.11|1996-09-14|3-MEDIUM|Clerk#000000661|0|y quick pinto beans wake. slyly re|61.1426|-149.877|61.1426|-149.877|
+2981|49|O|37776.79|1998-07-29|5-LOW|Clerk#000000299|0|hely among the express foxes. blithely stealthy requests cajole boldly. regu|61.1173|-149.861|61.1173|-149.861|
+2982|85|F|55582.94|1995-03-19|2-HIGH|Clerk#000000402|0|lyly. express theodolites affix slyly after the slyly speci|61.1347|-149.914|61.1347|-149.914|
diff --git a/hyracks-examples/hyracks-integration-tests/data/spatial.txt b/hyracks-examples/hyracks-integration-tests/data/spatial.txt
new file mode 100644
index 0000000..831e702
--- /dev/null
+++ b/hyracks-examples/hyracks-integration-tests/data/spatial.txt
@@ -0,0 +1,1079 @@
+42.3631|-71.065|42.3631|-71.065|all phase plumbing|
+42.1091|-70.696|42.1091|-70.696|gramercy cardiac diagnostic|
+40.8151|-73.0452|40.8151|-73.0452|-|
+40.8151|-73.0452|40.8151|-73.0452|bear mountain state park|
+42.2481|-71.174|42.2481|-71.174|domino's pizza|
+61.1201|-149.89|61.1201|-149.89|paul fiori|
+61.1501|-149.926|61.1501|-149.926|fire & flood svc|
+61.181|-149.814|61.181|-149.814|fire dept-hazardous materials|
+61.1517|-149.86|61.1517|-149.86|fire fighters smoke detector|
+61.1806|-149.814|61.1806|-149.814|fire marshal's office|
+61.1806|-149.775|61.1806|-149.775|fire marshall director|
+61.1806|-149.775|61.1806|-149.775|fire prevention div|
+61.1806|-149.775|61.1806|-149.775|fire service training|
+61.2113|-149.824|61.2113|-149.824|fire service training program|
+61.1967|-149.877|61.1967|-149.877|fireman's fund insurance|
+61.2164|-149.892|61.2164|-149.892|firenze design|
+61.1571|-149.883|61.1571|-149.883|fireplace gallery|
+61.2048|-149.834|61.2048|-149.834|firestar media svc|
+61.0956|-149.843|61.0956|-149.843|firestarters of alaska|
+61.1491|-149.809|61.1491|-149.809|firestoppers|
+61.1981|-149.871|61.1981|-149.871|fireweed 7|
+61.1982|-149.876|61.1982|-149.876|fireweed acupuncture herb|
+61.1924|-149.909|61.1924|-149.909|fireweed health care inc|
+61.2204|-149.728|61.2204|-149.728|fireweed lodge at lake creek|
+61.196|-149.864|61.196|-149.864|fireweed manor|
+61.1987|-149.889|61.1987|-149.889|fireweed mart|
+61.1984|-149.897|61.1984|-149.897|fireweed shoe repair|
+61.1897|-149.898|61.1897|-149.898|fireweed tuxedo|
+61.1228|-149.81|61.1228|-149.81|first & lasting impressions|
+61.1649|-149.881|61.1649|-149.881|first alaska contractors inc|
+61.1934|-149.887|61.1934|-149.887|first alaska mortgage|
+61.2164|-149.892|61.2164|-149.892|first alaskans institute|
+61.1932|-149.886|61.1932|-149.886|first american title ins co|
+61.2072|-149.888|61.2072|-149.888|first assembly of god church|
+61.2125|-149.904|61.2125|-149.904|first baptist church|
+61.2142|-149.806|61.2142|-149.806|first call media productions|
+61.1866|-149.923|61.1866|-149.923|first care medical ctrs|
+61.1089|-149.857|61.1089|-149.857|first choice realty & property|
+61.1024|-149.853|61.1024|-149.853|first choice roofing|
+61.1891|-149.906|61.1891|-149.906|do-r-best forestry|
+61.1891|-149.906|61.1891|-149.906|painting by english|
+61.1891|-149.906|61.1891|-149.906|houston painting co|
+61.1891|-149.906|61.1891|-149.906|berts mechnaical|
+61.1891|-149.906|61.1891|-149.906|industrial boiler & controls|
+61.1891|-149.906|61.1891|-149.906|foremans inc|
+61.1891|-149.906|61.1891|-149.906|alcan electrical & engineering|
+61.1891|-149.906|61.1891|-149.906|denali electric co|
+61.1891|-149.906|61.1891|-149.906|alaska infrred asp restoration|
+61.1891|-149.906|61.1891|-149.906|arnell icm company|
+61.1891|-149.906|61.1891|-149.906|pacific partition systems|
+61.1891|-149.906|61.1891|-149.906|associated professional entps|
+61.1891|-149.906|61.1891|-149.906|alcan general inc|
+61.1891|-149.906|61.1891|-149.906|asrc constructors inc|
+61.1891|-149.906|61.1891|-149.906|john-wayne construction co|
+61.1891|-149.906|61.1891|-149.906|underfoot enterprises|
+61.1891|-149.906|61.1891|-149.906|advance door systems inc|
+61.1891|-149.906|61.1891|-149.906|doorman service company|
+61.1891|-149.906|61.1891|-149.906|rdd asphalt restorations|
+61.1891|-149.906|61.1891|-149.906|l k general contractor|
+61.1891|-149.906|61.1891|-149.906|wiker roofing co|
+61.1891|-149.906|61.1891|-149.906|damco paving corp|
+61.1891|-149.906|61.1891|-149.906|international steel erectors|
+61.1891|-149.906|61.1891|-149.906|falcon masonry|
+61.1891|-149.906|61.1891|-149.906|wasler specialties|
+61.1891|-149.906|61.1891|-149.906|northeaton plastering|
+61.1891|-149.906|61.1891|-149.906|a1 fence llc|
+61.1891|-149.906|61.1891|-149.906|hickel construction & engrg|
+61.1891|-149.906|61.1891|-149.906|taco-loco products inc|
+61.1891|-149.906|61.1891|-149.906|je jones llc|
+61.1891|-149.906|61.1891|-149.906|alaska yellowpagescom inc|
+61.1891|-149.906|61.1891|-149.906|alaska tab & bind inc|
+61.1891|-149.906|61.1891|-149.906|sourdough studio|
+61.1891|-149.906|61.1891|-149.906|tundra times|
+61.1891|-149.906|61.1891|-149.906|travelhost of alaska|
+64.8541|-147.813|64.8541|-147.813|us land management bureau|
+64.8414|-147.606|64.8414|-147.606|us land management bureau|
+64.8371|-147.746|64.8371|-147.746|us law enforcement svc|
+64.8151|-147.707|64.8151|-147.707|us marshal|
+64.8371|-147.746|64.8371|-147.746|us migratory bird management|
+64.849|-147.813|64.849|-147.813|us mineral resources program|
+64.8425|-147.724|64.8425|-147.724|us passport agency|
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+64.8281|-147.812|64.8281|-147.812|us transportation dept|
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+64.8145|-147.772|64.8145|-147.772|us water resources|
+64.8541|-147.813|64.8541|-147.813|us water resources div|
+64.8169|-147.779|64.8169|-147.779|usa today|
+64.8378|-147.71|64.8378|-147.71|usgsa public building svc|
+64.8436|-147.722|64.8436|-147.722|usibelli coal mine inc|
+64.9401|-147.402|64.9401|-147.402|usibelli coal mine kbc|
+64.8426|-147.719|64.8426|-147.719|uskh architects engineers|
+64.8534|-147.811|64.8534|-147.811|utility services of alaska|
+64.9341|-147.928|64.9341|-147.928|v f grace inc|
+64.8393|-147.72|64.8393|-147.72|vagabond travel|
+64.8406|-147.731|64.8406|-147.731|valerie m therrien atty-law pc|
+64.9281|-147.865|64.9281|-147.865|vallata|
+64.8371|-147.716|64.8371|-147.716|valley kids|
+64.9414|-147.841|64.9414|-147.841|valley landscaping|
+64.8363|-147.79|64.8363|-147.79|valley of blessing church|
+64.8371|-147.716|64.8371|-147.716|valley ventures|
+64.8591|-147.917|64.8591|-147.917|valley visions consulting inc|
+64.8363|-147.79|64.8363|-147.79|value village|
+55.3801|-131.682|55.3801|-131.682|wolfs concrete finishing|
+55.3073|-131.528|55.3073|-131.528|whiteside enterprises|
+55.3801|-131.682|55.3801|-131.682|flooring services|
+55.3601|-131.681|55.3601|-131.681|floor decor and more|
+55.3279|-131.613|55.3279|-131.613|ohmers renderings|
+55.3129|-131.588|55.3129|-131.588|carson construction|
+55.3801|-131.682|55.3801|-131.682|a a a pest pros|
+55.3801|-131.682|55.3801|-131.682|aurora roofing|
+55.4299|-131.789|55.4299|-131.789|channel seamless gutter roofg|
+55.3801|-131.682|55.3801|-131.682|variety painting & roofing|
+55.3507|-131.671|55.3507|-131.671|hometown flooring|
+55.3801|-131.682|55.3801|-131.682|southeast carpets & draperies|
+55.3394|-131.636|55.3394|-131.636|channel electric inc|
+55.3801|-131.682|55.3801|-131.682|ever electric inc|
+55.3103|-131.582|55.3103|-131.582|jacks painting|
+55.3801|-131.682|55.3801|-131.682|larry d painter|
+55.3801|-131.682|55.3801|-131.682|trans alaska restaurant eqp|
+55.3801|-131.682|55.3801|-131.682|jacobson heating & rfrgn|
+55.3801|-131.682|55.3801|-131.682|ketchikan mechanical inc|
+55.3801|-131.682|55.3801|-131.682|southast fire prtection contrs|
+55.3424|-131.634|55.3424|-131.634|bob hulse plumbing inc|
+55.4097|-131.729|55.4097|-131.729|southeast construction inc|
+55.3801|-131.682|55.3801|-131.682|southeast backhoe service inc|
+55.3801|-131.682|55.3801|-131.682|ljs & sons|
+55.3462|-131.658|55.3462|-131.658|captains quarters & breakfast|
+55.3801|-131.682|55.3801|-131.682|pacific log & lumber ltd|
+55.3801|-131.682|55.3801|-131.682|phoenix logging co a partnr|
+55.3801|-131.682|55.3801|-131.682|ketchikan cutting co|
+55.3801|-131.682|55.3801|-131.682|gildersleeve logging co inc|
+55.3801|-131.682|55.3801|-131.682|northwest logging inc|
+55.3801|-131.682|55.3801|-131.682|evergreen timber llc|
+55.3801|-131.682|55.3801|-131.682|helicopter services inc|
+55.3801|-131.682|55.3801|-131.682|miller inc|
+61.5856|-149.316|61.5856|-149.316|alaska water conditioning inc|
+61.5781|-149.429|61.5781|-149.429|alaska waterski ctr|
+61.6141|-149.457|61.6141|-149.457|alaska weld|
+61.5801|-149.461|61.5801|-149.461|alaska well & pump|
+61.9071|-150.067|61.9071|-150.067|alaska winter excursions|
+61.5928|-149.392|61.5928|-149.392|alaska woodworks|
+61.6141|-149.457|61.6141|-149.457|alaska wool products|
+61.5792|-149.36|61.5792|-149.36|alaska's best satellite|
+61.6049|-149.463|61.6049|-149.463|alaska's cabin fever relief|
+61.6099|-149.328|61.6099|-149.328|alaska's nautical training|
+61.5531|-149.651|61.5531|-149.651|alaska's trails & tails|
+61.6141|-149.457|61.6141|-149.457|alaskamls.com|
+61.6141|-149.457|61.6141|-149.457|alaskan bail bonds|
+61.5531|-149.651|61.5531|-149.651|alaskan colors|
+61.6141|-149.457|61.6141|-149.457|alaskan distributors|
+61.7321|-150.12|61.7321|-150.12|alaskan dream espresso|
+61.6141|-149.457|61.6141|-149.457|alaskan electrical svc|
+61.582|-149.441|61.582|-149.441|alaskan family dental ctr|
+61.5818|-149.44|61.5818|-149.44|alaskan gold rush jewelers|
+61.6141|-149.457|61.6141|-149.457|alaskan hospitality baskets|
+61.7321|-150.12|61.7321|-150.12|alaskan host bed & breakfast|
+61.6308|-149.415|61.6308|-149.415|alaskan industries|
+61.5801|-149.461|61.5801|-149.461|alaskan marine documentation|
+61.5811|-149.444|61.5811|-149.444|alaskan musher|
+61.6521|-149.92|61.6521|-149.92|alaskan sled dogs|
+61.6141|-149.307|61.6141|-149.307|alaskan splendor b & b limo|
+61.6168|-149.328|61.6168|-149.328|alaskan tnt excavation|
+61.5714|-149.381|61.5714|-149.381|alaskan view motel|
+61.6521|-149.92|61.6521|-149.92|alaskian custom expeditions|
+61.5858|-149.376|61.5858|-149.376|alcan electric inc|
+61.5822|-149.463|61.5822|-149.463|all about herbs|
+61.5861|-149.303|61.5861|-149.303|all creatures veterinary clnc|
+61.5821|-149.438|61.5821|-149.438|all i saw cookware|
+61.6281|-149.338|61.6281|-149.338|all phase roofing|
+61.5771|-149.335|61.5771|-149.335|all star child care|
+61.5917|-149.464|61.5917|-149.464|all star construction|
+61.1927|-149.86|61.1927|-149.86|first christian church|
+61.1879|-149.85|61.1879|-149.85|first christian meth episc chr|
+61.1814|-149.849|61.1814|-149.849|first church of god|
+61.2104|-149.892|61.2104|-149.892|first church of the nazarene|
+61.2093|-149.903|61.2093|-149.903|first church-christ scientist|
+61.1481|-149.829|61.1481|-149.829|first class auto body|
+61.2161|-149.876|61.2161|-149.876|first class painting|
+61.1972|-149.75|61.1972|-149.75|first cme church|
+61.2066|-149.887|61.2066|-149.887|first command financial plan|
+61.2161|-149.876|61.2161|-149.876|first commodity traders/maxxis|
+61.195|-149.834|61.195|-149.834|first congregational church|
+61.2038|-149.808|61.2038|-149.808|first health svc corp|
+61.1228|-149.862|61.1228|-149.862|first interstate bank-alaska|
+61.2005|-149.785|61.2005|-149.785|first korean baptist church|
+61.181|-149.825|61.181|-149.825|first lms samoan church|
+61.1867|-149.919|61.1867|-149.919|first maintenance co|
+61.1955|-149.911|61.1955|-149.911|first maintenance inc|
+61.1089|-149.858|61.1089|-149.858|first medical ctr|
+61.1805|-149.889|61.1805|-149.889|first mental health|
+61.1534|-149.985|61.1534|-149.985|first missionary baptist chr|
+61.1901|-149.911|61.1901|-149.911|first mortgage inc|
+61.2122|-149.734|61.2122|-149.734|first national bank|
+61.1951|-149.906|61.1951|-149.906|first national bank|
+61.2043|-149.869|61.2043|-149.869|first national bank|
+61.2036|-149.869|61.2036|-149.869|first national bank|
+61.1883|-149.886|61.1883|-149.886|first national bank|
+61.2141|-149.864|61.2141|-149.864|first national bank|
+61.1955|-149.782|61.1955|-149.782|first national bank|
+61.2183|-149.894|61.2183|-149.894|first national bank|
+61.1417|-149.864|61.1417|-149.864|first national bank|
+61.1883|-149.883|61.1883|-149.883|first national bank alaska|
+61.2161|-149.876|61.2161|-149.876|first national bank jobline|
+61.2193|-149.869|61.2193|-149.869|first native baptist church|
+61.2191|-149.888|61.2191|-149.888|seward phoenix log|
+61.2191|-149.888|61.2191|-149.888|greatland graphics|
+61.2191|-149.888|61.2191|-149.888|conocophillips alaska inc|
+61.2191|-149.888|61.2191|-149.888|tonys enterprises|
+61.2191|-149.888|61.2191|-149.888|counter tops by rejio|
+61.2191|-149.888|61.2191|-149.888|fletchers masonry|
+61.2191|-149.888|61.2191|-149.888|anchor roofing construction|
+61.2191|-149.888|61.2191|-149.888|seamless flooring systems|
+61.2191|-149.888|61.2191|-149.888|edt security service|
+61.2191|-149.888|61.2191|-149.888|rock creek mining company|
+61.2191|-149.888|61.2191|-149.888|fairweather incorporated|
+61.2191|-149.888|61.2191|-149.888|swalling construction co ofc|
+61.1891|-149.906|61.1891|-149.906|posh house|
+61.2191|-149.888|61.2191|-149.888|freespan system inc|
+61.2191|-149.888|61.2191|-149.888|swank construction|
+61.1101|-149.857|61.1101|-149.857|guitreaus technical|
+61.1101|-149.857|61.1101|-149.857|casa llc|
+61.1101|-149.857|61.1101|-149.857|b & a mobile mix concrete|
+61.1101|-149.857|61.1101|-149.857|glacier chain supplies inc|
+61.1101|-149.857|61.1101|-149.857|jennies workshop inc|
+61.1101|-149.857|61.1101|-149.857|aaa american sign and lighting|
+61.1101|-149.857|61.1101|-149.857|patrick faherty|
+61.1101|-149.857|61.1101|-149.857|tom mortensen & assoc|
+61.1101|-149.857|61.1101|-149.857|bethel services inc|
+61.1101|-149.857|61.1101|-149.857|denali general contractors|
+61.1101|-149.857|61.1101|-149.857|h watt & scott inc|
+61.1101|-149.857|61.1101|-149.857|premier cnstr surveys llc|
+61.1101|-149.857|61.1101|-149.857|johnson construction|
+61.1101|-149.857|61.1101|-149.857|thomas development inc|
+61.1101|-149.857|61.1101|-149.857|t & m construction|
+61.1101|-149.857|61.1101|-149.857|rockford corporation|
+61.1101|-149.857|61.1101|-149.857|tam construction inc|
+61.1101|-149.857|61.1101|-149.857|crown pointe inc|
+61.1101|-149.857|61.1101|-149.857|arctic residential res corp|
+64.8591|-147.917|64.8591|-147.917|van wyhe rogers|
+64.8273|-147.715|64.8273|-147.715|variety motors|
+64.8281|-147.715|64.8281|-147.715|vector marketing corp|
+64.8552|-147.763|64.8552|-147.763|vend-alaska|
+64.8481|-147.684|64.8481|-147.684|verizon information svc|
+64.8522|-147.773|64.8522|-147.773|vertex insulation|
+64.8467|-147.703|64.8467|-147.703|veterans of foreign wars|
+64.8963|-147.662|64.8963|-147.662|vicki rayburn music|
+64.8372|-147.796|64.8372|-147.796|victorian parlor antiques|
+64.8312|-147.716|64.8312|-147.716|victory christian faith ctr|
+64.811|-147.71|64.811|-147.71|video machine inc|
+64.8971|-147.663|64.8971|-147.663|village mobile home park|
+64.85|-147.699|64.85|-147.699|vip dry cleaners & lndrmt|
+64.8389|-147.743|64.8389|-147.743|virgie's sari-sari|
+64.781|-148|64.781|-148|vision quest|
+64.8377|-147.718|64.8377|-147.718|vista travel inc|
+64.8248|-147.886|64.8248|-147.886|vital signs|
+64.818|-147.679|64.818|-147.679|vocational rehabilitation dept|
+64.8271|-147.79|64.8271|-147.79|voluntary taxes|
+64.8451|-147.812|64.8451|-147.812|volunteer action ctr|
+64.8311|-147.729|64.8311|-147.729|volunteers in policing|
+64.8454|-147.855|64.8454|-147.855|voorhees concrete cutting|
+64.8302|-147.744|64.8302|-147.744|george r vrablik md|
+64.8113|-147.91|64.8113|-147.91|w a inc|
+64.8271|-147.789|64.8271|-147.789|wagner excavating|
+64.8451|-147.698|64.8451|-147.698|wakefield builders|
+64.8586|-147.69|64.8586|-147.69|wal-mart supercenter|
+64.8507|-147.702|64.8507|-147.702|waldenbooks|
+64.8371|-147.716|64.8371|-147.716|wales tec inc|
+64.8449|-147.743|64.8449|-147.743|walkada apartments|
+64.8475|-147.706|64.8475|-147.706|wallace wallace & wakefield|
+64.8452|-147.714|64.8452|-147.714|walleri law offices|
+64.8125|-147.787|64.8125|-147.787|wallner excavating inc|
+55.3801|-131.682|55.3801|-131.682|usa today|
+55.3801|-131.682|55.3801|-131.682|sun glass designs|
+55.3801|-131.682|55.3801|-131.682|austin powder company|
+55.3801|-131.682|55.3801|-131.682|tongass substance screening|
+55.3801|-131.682|55.3801|-131.682|royalty co|
+55.3801|-131.682|55.3801|-131.682|rons plumbing & heating|
+55.3599|-131.687|55.3599|-131.687|candle lady|
+55.4381|-131.803|55.4381|-131.803|fluke signs north|
+55.3751|-131.718|55.3751|-131.718|sign pro of juneau|
+55.3421|-131.641|55.3421|-131.641|blue heron designs|
+55.3408|-131.64|55.3408|-131.64|gateway games|
+55.2978|-131.534|55.2978|-131.534|nathan jackson|
+55.3801|-131.682|55.3801|-131.682|alaska ship & drydock inc|
+55.3801|-131.682|55.3801|-131.682|don cunning|
+55.3421|-131.622|55.3421|-131.622|aero services|
+55.3801|-131.682|55.3801|-131.682|hanger|
+55.3801|-131.682|55.3801|-131.682|columbia helicopters inc|
+55.3801|-131.682|55.3801|-131.682|homestead skiffs llc|
+55.3267|-131.523|55.3267|-131.523|n picific tecn inc|
+55.3522|-131.685|55.3522|-131.685|ketchikan ranger district|
+55.5351|-133.014|55.5351|-133.014|b-3 contractors inc|
+55.5351|-133.014|55.5351|-133.014|phoenix logging company|
+55.5351|-133.014|55.5351|-133.014|prince wales electric and r|
+55.5351|-133.014|55.5351|-133.014|toms burner service|
+55.5351|-133.014|55.5351|-133.014|p & h construction|
+55.4691|-132.855|55.4691|-132.855|ziegler construction|
+55.5511|-133.081|55.5511|-133.081|rainbird drilling inc|
+55.5351|-133.014|55.5351|-133.014|larry lee trumble|
+55.5531|-133.097|55.5531|-133.097|maria elena f/v|
+55.5351|-133.014|55.5351|-133.014|wildfish co|
+55.4726|-131.793|55.4726|-131.793|carson marine charters inc|
+55.3801|-131.682|55.3801|-131.682|alaska general seafood|
+55.3801|-131.682|55.3801|-131.682|norquest seafoods inc|
+55.3801|-131.682|55.3801|-131.682|ocean point fisheries|
+61.5745|-149.562|61.5745|-149.562|all things wild taxidermy|
+61.7321|-150.12|61.7321|-150.12|all valley svc|
+61.5421|-149.419|61.5421|-149.419|all ways storage & rental co|
+61.5722|-149.702|61.5722|-149.702|all-n-1 svc|
+61.5743|-149.405|61.5743|-149.405|allen & petersen appliance ctr|
+61.578|-149.441|61.578|-149.441|allied communications|
+61.5826|-149.427|61.5826|-149.427|aloha dental care|
+61.5586|-149.351|61.5586|-149.351|alpenview medical svc|
+61.5844|-149.442|61.5844|-149.442|alpha counseling & education|
+61.5817|-149.472|61.5817|-149.472|alpine chiropractic ctr|
+61.6141|-149.457|61.6141|-149.457|alpine pure air & water prdcts|
+61.5761|-149.602|61.5761|-149.602|alpine septic pumping inc|
+61.6141|-149.457|61.6141|-149.457|alpine technologies|
+61.58|-149.434|61.58|-149.434|aluminum works|
+61.6002|-149.429|61.6002|-149.429|alyeska technologies a tech|
+61.569|-149.347|61.569|-149.347|ambassador window cleaning|
+61.5812|-149.448|61.5812|-149.448|america's lending group|
+61.6141|-149.457|61.6141|-149.457|american dream construction|
+61.6141|-149.457|61.6141|-149.457|american legion|
+61.6141|-149.457|61.6141|-149.457|american legion bingo|
+61.5969|-149.367|61.5969|-149.367|american marine hyperbarics|
+61.58|-149.4|61.58|-149.4|american park & sell|
+61.5848|-149.445|61.5848|-149.445|american red cross|
+61.5811|-149.444|61.5811|-149.444|american satellite|
+61.5733|-149.389|61.5733|-149.389|american tattoo|
+61.6141|-149.457|61.6141|-149.457|amigalaska productions|
+61.5952|-149.436|61.5952|-149.436|amvets post|
+61.5421|-149.419|61.5421|-149.419|amway distributors|
+61.5783|-149.362|61.5783|-149.362|amy henry's heated storage|
+61.7321|-150.12|61.7321|-150.12|anchor chiropractic healing|
+61.5691|-149.328|61.5691|-149.328|anchorage daily news|
+61.6141|-149.457|61.6141|-149.457|anchorage drywall|
+61.5819|-149.3|61.5819|-149.3|anchorage handyman svc|
+61.6431|-149.289|61.6431|-149.289|anchorage tank & welding|
+61.6431|-149.292|61.6431|-149.292|anchorage tank & welding inc|
+61.6228|-149.313|61.6228|-149.313|anchors away cruise outlet|
+61.2125|-149.894|61.2125|-149.894|first presbyterian church|
+61.1879|-149.886|61.1879|-149.886|first priority mortgage|
+61.1594|-149.835|61.1594|-149.835|first samoan church|
+61.2123|-149.854|61.2123|-149.854|first samoan stand by faith|
+61.1951|-149.945|61.1951|-149.945|first samoan united methodist|
+61.2138|-149.856|61.2138|-149.856|first spanish assemblies-god|
+61.1255|-149.864|61.1255|-149.864|first student|
+61.2066|-149.808|61.2066|-149.808|first tabernacle|
+61.2138|-149.896|61.2138|-149.896|first united methodist church|
+61.2161|-149.876|61.2161|-149.876|fish|
+61.1594|-149.888|61.1594|-149.888|fish & game dept|
+61.1806|-149.775|61.1806|-149.775|fish & wildlife protection|
+61.1101|-149.857|61.1101|-149.857|fish alaska magazine|
+61.1541|-149.958|61.1541|-149.958|fish site|
+61.1268|-149.947|61.1268|-149.947|fish talk consulting|
+61.0931|-149.785|61.0931|-149.785|fish wish charters|
+61.1901|-149.892|61.1901|-149.892|fishboy outfitters|
+61.2183|-149.889|61.2183|-149.889|fisherman's express|
+61.2164|-149.882|61.2164|-149.882|fishing lodge inc|
+61.2161|-149.876|61.2161|-149.876|fit for health|
+61.219|-149.792|61.219|-149.792|fitzgerald photography|
+61.2188|-149.892|61.2188|-149.892|five fifteen club|
+61.2143|-149.837|61.2143|-149.837|five one victor|
+61.1608|-149.835|61.1608|-149.835|five star automotive repair|
+61.1886|-149.944|61.1886|-149.944|five star entertainment|
+61.1201|-149.89|61.1201|-149.89|five star insultators inc|
+61.1201|-149.89|61.1201|-149.89|five star roofing|
+61.1585|-149.872|61.1585|-149.872|fivestarappliance & electronic|
+61.195|-149.892|61.195|-149.892|flash tan|
+61.0895|-149.694|61.0895|-149.694|flattop technical svc|
+61.2201|-149.831|61.2201|-149.831|fleenor paper co|
+61.1663|-149.867|61.1663|-149.867|fleet liquidators|
+61.2138|-149.906|61.2138|-149.906|hugh w fleischer|
+61.2193|-149.902|61.2193|-149.902|hugh w fleischer|
+61.1201|-149.89|61.1201|-149.89|fletcher's masonry|
+61.1601|-149.984|61.1601|-149.984|flight alaska inc|
+61.1101|-149.857|61.1101|-149.857|bn contracting inc|
+61.1101|-149.857|61.1101|-149.857|twa home repair service llc|
+61.1101|-149.857|61.1101|-149.857|faltz deck & patio builders|
+61.1101|-149.857|61.1101|-149.857|four seasons|
+61.1101|-149.857|61.1101|-149.857|timberline homes inc|
+61.1101|-149.857|61.1101|-149.857|janigo construction|
+61.1101|-149.857|61.1101|-149.857|kopitch construction|
+61.1101|-149.857|61.1101|-149.857|north slopes inspection dist|
+61.1101|-149.857|61.1101|-149.857|tuboscoope|
+61.1101|-149.857|61.1101|-149.857|parker drilling company|
+61.1101|-149.857|61.1101|-149.857|record center|
+61.1101|-149.857|61.1101|-149.857|julian creek mining|
+61.1101|-149.857|61.1101|-149.857|jon|
+61.1101|-149.857|61.1101|-149.857|salmon express|
+61.1101|-149.857|61.1101|-149.857|interceptor owners fv mu|
+61.1101|-149.857|61.1101|-149.857|alaska deep sea adventure|
+61.1101|-149.857|61.1101|-149.857|northern greens|
+61.1101|-149.857|61.1101|-149.857|arctic green llc|
+61.1101|-149.857|61.1101|-149.857|alpine tree & brush cutng svcs|
+61.1101|-149.857|61.1101|-149.857|landscape resources corp|
+61.1101|-149.857|61.1101|-149.857|smith cable systems inc|
+61.1101|-149.857|61.1101|-149.857|t a b electric inc|
+61.1101|-149.857|61.1101|-149.857|bomax inc|
+61.1101|-149.857|61.1101|-149.857|arctic lights electric inc|
+61.1101|-149.857|61.1101|-149.857|rams horn electric inc|
+61.1101|-149.857|61.1101|-149.857|toklat electric inc|
+61.1101|-149.857|61.1101|-149.857|cassidys plumbing & htg llc|
+61.1101|-149.857|61.1101|-149.857|aarow pump & well service|
+61.1101|-149.857|61.1101|-149.857|aurora refrigeration inc|
+61.1101|-149.857|61.1101|-149.857|denali fire protection|
+61.1101|-149.857|61.1101|-149.857|noble mechanical|
+61.1101|-149.857|61.1101|-149.857|ancroge roofing|
+61.1101|-149.857|61.1101|-149.857|premier roofing co|
+61.1101|-149.857|61.1101|-149.857|first choice roofing|
+61.1101|-149.857|61.1101|-149.857|twin peaks roofing|
+64.8459|-147.759|64.8459|-147.759|wallpaper warehouse|
+64.8426|-147.725|64.8426|-147.725|walsh kelliher & sharp|
+64.9401|-147.402|64.9401|-147.402|laurie walton|
+64.9401|-147.402|64.9401|-147.402|lonnie ward|
+64.8331|-147.647|64.8331|-147.647|wareforce inc|
+64.8371|-147.716|64.8371|-147.716|sheree warner|
+64.8574|-147.759|64.8574|-147.759|wartes floor covering|
+64.836|-147.727|64.836|-147.727|warwick & schikora|
+64.8132|-147.76|64.8132|-147.76|waste management-star|
+64.8451|-147.96|64.8451|-147.96|water wagon llc|
+64.8891|-147.851|64.8891|-147.851|watercolors by nikki kinne|
+64.8151|-147.707|64.8151|-147.707|waterman|
+64.8363|-147.803|64.8363|-147.803|wayland baptist university|
+64.8298|-147.611|64.8298|-147.611|wayland baptist university|
+64.8989|-147.701|64.8989|-147.701|wayne's air supply|
+64.8371|-147.716|64.8371|-147.716|wdtm|
+64.8147|-147.706|64.8147|-147.706|weaver brothers inc|
+64.8451|-147.812|64.8451|-147.812|web weavers|
+64.8386|-147.788|64.8386|-147.788|weber stump grinding|
+64.8372|-147.768|64.8372|-147.768|mark weber|
+64.8151|-147.707|64.8151|-147.707|webmasters|
+64.843|-147.722|64.843|-147.722|pamela w webster|
+64.8426|-147.725|64.8426|-147.725|wedbush morgan securities|
+64.8615|-147.723|64.8615|-147.723|wedgewood resort|
+64.8694|-147.067|64.8694|-147.067|weidner electric rebuilders|
+64.8404|-147.724|64.8404|-147.724|weights & measures dept|
+64.9686|-147.577|64.9686|-147.577|welding shop|
+64.8497|-147.732|64.8497|-147.732|well street art co|
+64.8861|-147.587|64.8861|-147.587|weller elementary school|
+64.8508|-147.703|64.8508|-147.703|wells fargo bank|
+64.841|-147.72|64.841|-147.72|wells fargo bank|
+64.8375|-147.721|64.8375|-147.721|wells fargo bank|
+64.849|-147.813|64.849|-147.813|wells fargo bank|
+55.3801|-131.682|55.3801|-131.682|rainbird drilling inc|
+55.3801|-131.682|55.3801|-131.682|trident seafoods corporation|
+55.3603|-131.702|55.3603|-131.702|hals equipment & supplies|
+55.7511|-132.865|55.7511|-132.865|southern se reg aqucltre assn|
+55.7511|-132.865|55.7511|-132.865|miguel n marin|
+60.3311|-151.284|60.3311|-151.284|heath r duncan|
+60.3311|-151.284|60.3311|-151.284|coho partnership|
+60.3311|-151.284|60.3311|-151.284|tarma grooming|
+60.4341|-151.283|60.4341|-151.283|whisper wind farm & stables|
+60.3311|-151.284|60.3311|-151.284|coopers wunded bear farms kenl|
+60.3311|-151.284|60.3311|-151.284|webb fish co|
+60.3311|-151.284|60.3311|-151.284|moerliens general contractor|
+60.3311|-151.284|60.3311|-151.284|rozak excavating and cnstr|
+60.3311|-151.284|60.3311|-151.284|sundance construction company|
+60.4311|-151.286|60.4311|-151.286|online systems|
+60.3311|-151.284|60.3311|-151.284|matlock ltd|
+60.3311|-151.284|60.3311|-151.284|silver fox slippers|
+60.3311|-151.284|60.3311|-151.284|salamander pads incorporated|
+60.3311|-151.284|60.3311|-151.284|gates construction inc|
+60.3191|-151.296|60.3191|-151.296|smileys custom contracting|
+60.3311|-151.284|60.3311|-151.284|kasilof construction company|
+60.3311|-151.284|60.3311|-151.284|earth works|
+60.3311|-151.284|60.3311|-151.284|salamander exhaust wraps inc|
+60.5563|-151.241|60.5563|-151.241|olgas jewelry|
+60.6331|-151.163|60.6331|-151.163|bj services company|
+60.6331|-151.163|60.6331|-151.163|national oilwell|
+60.6331|-151.163|60.6331|-151.163|industrial water treatment|
+60.6331|-151.163|60.6331|-151.163|h p parts & machines|
+60.5551|-151.245|60.5551|-151.245|satech|
+60.6331|-151.163|60.6331|-151.163|artic instilation & coating|
+60.5506|-151.141|60.5506|-151.141|beaver creek docks inc|
+60.5681|-151.281|60.5681|-151.281|porta blast and industrial|
+60.5465|-151.147|60.5465|-151.147|nicks ironworks|
+60.6331|-151.163|60.6331|-151.163|metal magic|
+60.5578|-151.116|60.5578|-151.116|cook inlet stone products|
+61.6182|-149.385|61.6182|-149.385|anderson door|
+61.6141|-149.457|61.6141|-149.457|angel haven lodge|
+61.5765|-149.407|61.5765|-149.407|angel nails|
+61.6091|-149.77|61.6091|-149.77|animal food warehouse|
+61.5821|-149.438|61.5821|-149.438|annabells bargain books|
+61.6183|-149.373|61.6183|-149.373|antonovich contracting|
+61.6131|-149.403|61.6131|-149.403|apd enterprise|
+61.6352|-149.265|61.6352|-149.265|apex surveying & consulting|
+61.5751|-149.645|61.5751|-149.645|apostolic worship ctr|
+61.6168|-149.374|61.6168|-149.374|appraisal co of mat-su|
+61.5939|-149.43|61.5939|-149.43|aqua vac|
+61.5792|-149.495|61.5792|-149.495|arby's|
+61.6141|-149.457|61.6141|-149.457|archibald drilling svc|
+61.5829|-149.448|61.5829|-149.448|architects alaska|
+61.5938|-149.387|61.5938|-149.387|arctic builders source inc|
+61.5849|-149.38|61.5849|-149.38|arctic circle club of n amer|
+61.5729|-149.389|61.5729|-149.389|arctic custom guns|
+61.5823|-149.462|61.5823|-149.462|arctic flame|
+61.57|-149.331|61.57|-149.331|arctic fox taxidermy studio|
+61.5821|-149.438|61.5821|-149.438|arctic rose fine fashions|
+61.6141|-149.457|61.6141|-149.457|arctic siding & supply|
+61.6115|-149.331|61.6115|-149.331|arctic sun distributors|
+61.6091|-149.77|61.6091|-149.77|arctic transmissions|
+61.6141|-149.457|61.6141|-149.457|walter r armstrong dds|
+61.5826|-149.427|61.5826|-149.427|armured usa inc|
+61.5976|-149.366|61.5976|-149.366|army national guard|
+61.5976|-149.366|61.5976|-149.366|army national guard recruiting|
+61.5531|-149.651|61.5531|-149.651|arnold gagnon contracting|
+61.5531|-149.651|61.5531|-149.651|arrowhead environmental svc|
+61.5883|-149.456|61.5883|-149.456|artistry of movement|
+61.6249|-149.435|61.6249|-149.435|ask educational computer|
+61.6141|-149.457|61.6141|-149.457|aspen construction|
+61.5709|-149.452|61.5709|-149.452|assembly of god-wasilla|
+61.6651|-149.465|61.6651|-149.465|attic antiques & collectibles|
+61.5841|-149.441|61.5841|-149.441|attorney's process svc|
+61.1571|-149.883|61.1571|-149.883|flight deck pizza|
+61.2198|-149.733|61.2198|-149.733|flo's pancake house|
+61.1863|-149.976|61.1863|-149.976|floats alaska|
+61.2161|-149.876|61.2161|-149.876|floor max|
+61.2031|-149.749|61.2031|-149.749|floor seasons inc|
+61.1644|-149.897|61.1644|-149.897|floor supply|
+61.1834|-149.866|61.1834|-149.866|flooring designs|
+61.1731|-149.889|61.1731|-149.889|floral expressions|
+61.1089|-149.854|61.1089|-149.854|floral expressions|
+61.1951|-149.916|61.1951|-149.916|floral expressions|
+61.2157|-149.821|61.2157|-149.821|floral expressions|
+61.1372|-149.954|61.1372|-149.954|floral expressions|
+61.1955|-149.737|61.1955|-149.737|floral expressions|
+61.1444|-149.867|61.1444|-149.867|florales|
+61.2178|-149.882|61.2178|-149.882|florcraft carpet one|
+61.1824|-149.849|61.1824|-149.849|flores d'columbia|
+61.2161|-149.876|61.2161|-149.876|florio engineering science|
+61.2022|-149.84|61.2022|-149.84|flowerama|
+61.2099|-149.762|61.2099|-149.762|flowers by june|
+61.1951|-149.84|61.1951|-149.84|flowers for the moment|
+61.1069|-149.859|61.1069|-149.859|floyd's garage|
+61.1635|-149.881|61.1635|-149.881|fluid machinery|
+61.1201|-149.89|61.1201|-149.89|flutissimo|
+61.1902|-149.908|61.1902|-149.908|fly by night club|
+61.2104|-149.857|61.2104|-149.857|fly guys|
+61.1771|-149.97|61.1771|-149.97|fly in restaurant|
+61.1859|-149.976|61.1859|-149.976|fly north air charter|
+61.2171|-149.9|61.2171|-149.9|flying colors|
+61.1162|-149.755|61.1162|-149.755|flying colors inc|
+61.1381|-149.844|61.1381|-149.844|flying dutchman european pstry|
+61.1775|-149.941|61.1775|-149.941|flying machine restaurant|
+61.1938|-149.878|61.1938|-149.878|flypaper|
+61.1571|-149.883|61.1571|-149.883|fmc energy systems|
+61.1541|-149.958|61.1541|-149.958|fnaws|
+61.135|-149.88|61.135|-149.88|fnw/ferguson|
+61.1101|-149.857|61.1101|-149.857|all weather inc|
+61.1101|-149.857|61.1101|-149.857|alaska standard roofing|
+61.1101|-149.857|61.1101|-149.857|meehleis steel of north inc|
+61.1101|-149.857|61.1101|-149.857|m w drilling inc|
+61.1101|-149.857|61.1101|-149.857|alpine drilling & enterprises|
+61.1101|-149.857|61.1101|-149.857|ak sealco|
+61.1101|-149.857|61.1101|-149.857|yukon pumping service inc|
+61.1101|-149.857|61.1101|-149.857|parker masonry & tile|
+61.1101|-149.857|61.1101|-149.857|interior wall systems inc|
+61.1101|-149.857|61.1101|-149.857|far north builders llc|
+61.1101|-149.857|61.1101|-149.857|insulate alaska|
+61.1101|-149.857|61.1101|-149.857|california closet co|
+61.1101|-149.857|61.1101|-149.857|absolute environmental svcs|
+61.1101|-149.857|61.1101|-149.857|lawson roofing & remodeling in|
+61.1101|-149.857|61.1101|-149.857|earths bounty foods llc|
+61.1101|-149.857|61.1101|-149.857|alaska canine cookies inc|
+61.1101|-149.857|61.1101|-149.857|fishermans wild alskan seafood|
+61.1101|-149.857|61.1101|-149.857|alaska glacier refreshments|
+61.2141|-149.864|61.2141|-149.864|northern management services|
+61.2171|-149.9|61.2171|-149.9|mc lin contractors inc|
+61.2171|-149.9|61.2171|-149.9|northern services|
+61.2171|-149.9|61.2171|-149.9|dar-con corporation|
+61.2171|-149.9|61.2171|-149.9|alaska tree doctor|
+61.2171|-149.9|61.2171|-149.9|williwaw publishing co|
+61.2171|-149.9|61.2171|-149.9|anchorage daily news inc|
+61.2171|-149.9|61.2171|-149.9|mcclathchy newspapers inc|
+61.2171|-149.9|61.2171|-149.9|p s publications|
+61.2171|-149.9|61.2171|-149.9|alaska fiberglass solutions|
+61.2171|-149.9|61.2171|-149.9|polaris insulation ltd|
+61.2171|-149.9|61.2171|-149.9|urethane alaska|
+61.2171|-149.9|61.2171|-149.9|dls supply|
+61.2171|-149.9|61.2171|-149.9|stewart construction co|
+61.2171|-149.9|61.2171|-149.9|wruck wade crpting instlltions|
+61.2171|-149.9|61.2171|-149.9|service one heating & cooling|
+64.8487|-147.704|64.8487|-147.704|wells fargo financial|
+64.8486|-147.705|64.8486|-147.705|wells fargo home mortgage inc|
+64.8087|-147.71|64.8087|-147.71|wells repair|
+64.8363|-147.758|64.8363|-147.758|wendy's|
+64.8476|-147.704|64.8476|-147.704|wendy's|
+64.8302|-147.744|64.8302|-147.744|william w wennen md|
+64.8476|-147.812|64.8476|-147.812|todd z wentz dds|
+64.8144|-147.756|64.8144|-147.756|pamela wescott|
+64.8183|-147.778|64.8183|-147.778|west coast distr|
+64.8494|-147.818|64.8494|-147.818|west valley high school|
+64.849|-147.822|64.849|-147.822|west valley vision ctr inc|
+64.8367|-147.716|64.8367|-147.716|west wind construction|
+64.8127|-147.772|64.8127|-147.772|western mechanical inc|
+64.8143|-147.751|64.8143|-147.751|western power & equipment corp|
+64.842|-147.721|64.842|-147.721|western travel|
+64.8403|-147.714|64.8403|-147.714|westmark fairbanks hotel|
+64.8371|-147.881|64.8371|-147.881|westside video|
+64.8151|-147.707|64.8151|-147.707|white birch ent inc|
+64.8151|-147.707|64.8151|-147.707|white environmental consultant|
+64.8541|-147.81|64.8541|-147.81|whole earth grocery & deli|
+64.8878|-147.496|64.8878|-147.496|wholesome touch|
+64.8299|-147.728|64.8299|-147.728|wic food program|
+64.8132|-147.762|64.8132|-147.762|wick constructors inc|
+64.8372|-147.713|64.8372|-147.713|wilbur brothers sheet metal|
+64.7927|-148.036|64.7927|-148.036|wild alaska-ktm-husaberg|
+64.8717|-147.819|64.8717|-147.819|wild pond therapeutic massage|
+64.8527|-147.686|64.8527|-147.686|wild rose performance horse|
+64.8371|-147.811|64.8371|-147.811|wilderness cache ceramics|
+64.846|-147.705|64.846|-147.705|wilderness canoe adventures|
+64.9064|-147.726|64.9064|-147.726|wilderness fishing inc|
+64.9347|-147.56|64.9347|-147.56|wildview cabin vacation home|
+64.8861|-147.677|64.8861|-147.677|wildwood mobile home court|
+64.8302|-147.744|64.8302|-147.744|william h montano inc|
+60.6673|-151.311|60.6673|-151.311|sign works|
+60.6997|-151.38|60.6997|-151.38|kenai neon sign company|
+60.5658|-151.244|60.5658|-151.244|everts air fuel inc|
+60.6331|-151.163|60.6331|-151.163|stans drywall painting|
+60.6331|-151.163|60.6331|-151.163|leuenhagens drywall & paint|
+60.6331|-151.163|60.6331|-151.163|independent concrete entrprs|
+60.6201|-151.332|60.6201|-151.332|spectrum services inc|
+60.5004|-151.276|60.5004|-151.276|kelly electric inc|
+60.6331|-151.163|60.6331|-151.163|kachemak electric co inc|
+60.6331|-151.163|60.6331|-151.163|mount spurr cabinets & mllwk|
+60.6901|-151.321|60.6901|-151.321|northland drilling|
+60.6676|-151.29|60.6676|-151.29|water systems & service|
+60.6331|-151.163|60.6331|-151.163|peninsula drilling|
+60.5632|-151.266|60.5632|-151.266|hansons roofing|
+60.6331|-151.163|60.6331|-151.163|duct or sheetmetal inc|
+60.6331|-151.163|60.6331|-151.163|miller sheet metal & heating|
+60.6509|-151.342|60.6509|-151.342|rezins concrete|
+60.5601|-151.107|60.5601|-151.107|russs construction co|
+60.5123|-151.275|60.5123|-151.275|rutherford floor covering|
+60.6076|-151.325|60.6076|-151.325|grace painting|
+60.6331|-151.163|60.6331|-151.163|k i m c o inc|
+60.5175|-151.235|60.5175|-151.235|mikes plumbing & heating|
+60.5535|-151.108|60.5535|-151.108|whites plumbing & heating|
+60.5614|-151.275|60.5614|-151.275|struempler plumbing|
+60.5647|-151.195|60.5647|-151.195|everything electric|
+60.6331|-151.163|60.6331|-151.163|brooks electric|
+60.6331|-151.163|60.6331|-151.163|cook inlet sign & lighting|
+60.6331|-151.163|60.6331|-151.163|pacific star seafoods inc|
+60.6331|-151.163|60.6331|-151.163|inlet salmon|
+60.6331|-151.163|60.6331|-151.163|salamatof seafoods inc|
+60.6678|-151.31|60.6678|-151.31|alaska metal|
+60.5003|-151.276|60.5003|-151.276|wjr ltd|
+60.6331|-151.163|60.6331|-151.163|efta net hanging|
+61.5855|-149.326|61.5855|-149.326|audio services corp|
+61.5979|-149.437|61.5979|-149.437|aunty cheryl's child care|
+61.6141|-149.457|61.6141|-149.457|aurora academy|
+61.5799|-149.461|61.5799|-149.461|aurora cleaning svc|
+61.5845|-149.337|61.5845|-149.337|aurora dental ctr|
+61.5351|-149.558|61.5351|-149.558|aurora enterprises|
+61.5811|-149.45|61.5811|-149.45|aurora flooring|
+61.5793|-149.442|61.5793|-149.442|aurora imports|
+61.5661|-149.313|61.5661|-149.313|aurora portable toilets|
+61.6141|-149.457|61.6141|-149.457|auto solutions|
+61.5786|-149.332|61.5786|-149.332|autodidactic press|
+61.5811|-149.45|61.5811|-149.45|avant gardens|
+61.5825|-149.429|61.5825|-149.429|avanti corp|
+61.6141|-149.457|61.6141|-149.457|avon independent sales rep|
+61.5531|-149.651|61.5531|-149.651|avon products|
+61.5531|-149.651|61.5531|-149.651|avp distributors|
+61.5698|-149.62|61.5698|-149.62|axberg builders|
+61.6141|-149.457|61.6141|-149.457|b & b farms|
+61.5474|-149.458|61.5474|-149.458|b & e landscaping & excavation|
+61.5825|-149.429|61.5825|-149.429|b & k daniel enterprises inc|
+61.5955|-149.423|61.5955|-149.423|b & r communications|
+61.5801|-149.461|61.5801|-149.461|b d builders|
+61.5785|-149.415|61.5785|-149.415|b howard & assoc|
+61.6402|-149.34|61.6402|-149.34|b original signs|
+61.583|-149.457|61.583|-149.457|back & neck pain relief ctr|
+61.5907|-149.295|61.5907|-149.295|bagels alaska|
+61.6141|-149.457|61.6141|-149.457|bailey construction management|
+61.5933|-149.397|61.5933|-149.397|bailey's backhoe|
+61.6091|-149.77|61.6091|-149.77|bailey's furniture outlet|
+61.577|-149.411|61.577|-149.411|bailey's sleep gallery|
+61.6078|-149.322|61.6078|-149.322|bald mountain landscape co|
+61.6131|-149.397|61.6131|-149.397|bald mountain lumber|
+61.6648|-149.372|61.6648|-149.372|baldy mountain rental|
+61.5531|-149.651|61.5531|-149.651|bales construction|
+61.5811|-149.45|61.5811|-149.45|banana pepper espresso|
+61.583|-149.457|61.583|-149.457|bandwagon skate & snowboard|
+61.1955|-149.9|61.1955|-149.9|focus co|
+61.1844|-149.897|61.1844|-149.897|focus hair salon|
+61.1901|-149.892|61.1901|-149.892|fof communications|
+61.1444|-149.867|61.1444|-149.867|foley & foley|
+61.1955|-149.9|61.1955|-149.9|follett & assoc|
+61.1893|-149.887|61.1893|-149.887|fonte' coffee roaster|
+61.2174|-149.888|61.2174|-149.888|fonte' coffee roaster|
+61.2227|-149.842|61.2227|-149.842|food bank of alaska|
+61.1263|-149.872|61.1263|-149.872|food services of america|
+61.1138|-149.866|61.1138|-149.866|food transportation svc|
+61.2157|-149.821|61.2157|-149.821|foot locker|
+61.2174|-149.888|61.2174|-149.888|foot locker|
+61.1855|-149.868|61.1855|-149.868|foot locker|
+61.1951|-149.873|61.1951|-149.873|foot locker|
+61.1444|-149.867|61.1444|-149.867|foot locker|
+61.1883|-149.735|61.1883|-149.735|foothills self storage|
+61.2161|-149.876|61.2161|-149.876|footprint productions|
+61.2161|-149.876|61.2161|-149.876|for sale by owner alaska|
+61.1893|-149.888|61.1893|-149.888|for sale by owner assistance|
+61.2174|-149.888|61.2174|-149.888|for your cell only|
+61.1914|-149.886|61.1914|-149.886|ford motor credit co|
+61.1541|-149.958|61.1541|-149.958|kurt ford|
+61.1259|-149.717|61.1259|-149.717|forest & land management inc|
+61.2193|-149.902|61.2193|-149.902|forest oil corp|
+61.1879|-149.886|61.1879|-149.886|forestry div|
+61.1372|-149.912|61.1372|-149.912|forget me not assisted living|
+61.1101|-149.857|61.1101|-149.857|forget me not demos|
+61.1791|-149.94|61.1791|-149.94|forget me not hair & nail sln|
+61.2031|-149.749|61.2031|-149.749|forget-me-not business|
+61.1914|-149.877|61.1914|-149.877|forget-me-not rubber stamps|
+61.1944|-149.883|61.1944|-149.883|fortier & mikko|
+61.1923|-149.886|61.1923|-149.886|forty niner transportation inc|
+61.2123|-149.854|61.2123|-149.854|forward amusement co|
+61.2161|-149.876|61.2161|-149.876|fosler law group|
+61.2171|-149.9|61.2171|-149.9|accel fire systems inc|
+61.1125|-149.861|61.1125|-149.861|mr rooter|
+61.1419|-149.896|61.1419|-149.896|picture perfect pntg & drywall|
+61.145|-149.878|61.145|-149.878|power electric & general contg|
+61.1044|-149.865|61.1044|-149.865|alaska refinishers|
+61.1444|-149.876|61.1444|-149.876|ats alaska inc|
+61.1|-149.85|61.1|-149.85|alaska contrs & engineers llc|
+61.1105|-149.861|61.1105|-149.861|alaska dream kitchens|
+61.1286|-149.957|61.1286|-149.957|arctic enterprises|
+61.1201|-149.89|61.1201|-149.89|integrity framing|
+61.112|-149.871|61.112|-149.871|hammer roofing|
+61.1427|-149.864|61.1427|-149.864|gallos|
+61.1212|-149.947|61.1212|-149.947|novakovichs enterprises inc|
+61.1228|-149.939|61.1228|-149.939|blackfrog specialties llp|
+61.1093|-149.871|61.1093|-149.871|firstmark homes corp|
+61.145|-149.878|61.145|-149.878|grose brothers|
+61.1191|-149.871|61.1191|-149.871|swanson general contractors|
+61.1003|-149.856|61.1003|-149.856|sheehan drywall inc|
+61.1113|-149.872|61.1113|-149.872|quality northern drywall|
+61.1084|-149.861|61.1084|-149.861|foam & coating statewide|
+61.144|-149.878|61.144|-149.878|cornerstone tile|
+61.1426|-149.877|61.1426|-149.877|rinos tile & stone|
+61.1173|-149.861|61.1173|-149.861|cm toms carpentry|
+61.1347|-149.914|61.1347|-149.914|gregs carpentry plus|
+61.1291|-149.951|61.1291|-149.951|jelles bent nail|
+61.1116|-149.862|61.1116|-149.862|dreyers of alaska distributor|
+61.144|-149.893|61.144|-149.893|creative kitchen designs inc|
+61.1148|-149.867|61.1148|-149.867|pacific drilling ltd|
+61.1178|-149.88|61.1178|-149.88|digger dans backhoe|
+61.2191|-149.888|61.2191|-149.888|ebco|
+61.2191|-149.888|61.2191|-149.888|anchorage glacier pilots inc|
+61.2191|-149.888|61.2191|-149.888|mini-brute service inc|
+64.8403|-147.784|64.8403|-147.784|william pike consulting|
+64.843|-147.722|64.843|-147.722|william r fairbanks investment|
+64.8421|-147.725|64.8421|-147.725|william r satterberg jr law|
+64.8631|-147.758|64.8631|-147.758|williams express|
+64.8476|-147.704|64.8476|-147.704|williams express|
+64.826|-147.714|64.826|-147.714|williams express|
+64.9401|-147.402|64.9401|-147.402|susan williamson|
+64.8436|-147.722|64.8436|-147.722|willis of alaska inc|
+64.8375|-147.812|64.8375|-147.812|willow creek clothing llc|
+64.8302|-147.744|64.8302|-147.744|willow physical therapy|
+64.8615|-147.722|64.8615|-147.722|willow woods apartments|
+64.8496|-147.718|64.8496|-147.718|wilson & wilson|
+64.8414|-147.713|64.8414|-147.713|wilton adjustment svc|
+64.8426|-147.72|64.8426|-147.72|winfree law office|
+64.8371|-147.716|64.8371|-147.716|mary c wing|
+64.811|-147.71|64.811|-147.71|wingfoot commercial tire systs|
+64.8151|-147.707|64.8151|-147.707|wings|
+64.8098|-147.764|64.8098|-147.764|wire communications inc|
+64.8515|-147.706|64.8515|-147.706|wireless retail inc|
+64.856|-147.809|64.856|-147.809|wok n roll express|
+64.856|-147.809|64.856|-147.809|wok n' roll express|
+64.8488|-147.811|64.8488|-147.811|wolf run restaurant|
+64.856|-147.809|64.856|-147.809|timothy j woller dds|
+64.8331|-147.647|64.8331|-147.647|wolverine supply|
+64.8547|-147.754|64.8547|-147.754|women & children ctr|
+64.8151|-147.707|64.8151|-147.707|women's center|
+64.8516|-147.709|64.8516|-147.709|women's health midwifery svc|
+64.8411|-147.718|64.8411|-147.718|brett m wood|
+64.8818|-147.638|64.8818|-147.638|woodcraft unlimited|
+64.8389|-147.87|64.8389|-147.87|woodriver elementary school|
+64.8596|-147.73|64.8596|-147.73|woodway|
+64.9234|-147.744|64.9234|-147.744|work in progress|
+64.9271|-147.716|64.9271|-147.716|work in progress|
+64.8725|-147.59|64.8725|-147.59|work man|
+60.6331|-151.163|60.6331|-151.163|gamas designs|
+60.5601|-151.186|60.5601|-151.186|nordic log homes|
+60.6331|-151.163|60.6331|-151.163|hall quality builders inc|
+60.5751|-151.311|60.5751|-151.311|agrium us inc|
+60.5681|-151.27|60.5681|-151.27|online systems|
+60.5585|-151.252|60.5585|-151.252|j c penny catalog|
+60.6331|-151.163|60.6331|-151.163|deans peninsula printing|
+60.6331|-151.163|60.6331|-151.163|arctic printing|
+60.6331|-151.163|60.6331|-151.163|peninsula clarion|
+60.5602|-151.244|60.5602|-151.244|printers ink|
+60.6331|-151.163|60.6331|-151.163|lowestein construction|
+60.6331|-151.163|60.6331|-151.163|redoubt/bering pcf joint ventr|
+60.5091|-151.146|60.5091|-151.146|quality asphalt|
+60.6331|-151.163|60.6331|-151.163|commercial auto repr eqp svcs|
+60.5571|-151.062|60.5571|-151.062|peninsula construction inc|
+60.7016|-151.318|60.7016|-151.318|troy built construction|
+60.6331|-151.163|60.6331|-151.163|ace|
+60.6331|-151.163|60.6331|-151.163|brown construction company|
+60.5677|-151.204|60.5677|-151.204|scotts construction|
+60.6331|-151.163|60.6331|-151.163|kenneth r puch construction|
+60.6671|-151.33|60.6671|-151.33|veal construction|
+60.6331|-151.163|60.6331|-151.163|tng builders|
+60.5007|-151.276|60.5007|-151.276|dan sterchi construction|
+60.5579|-151.058|60.5579|-151.058|c & o builders|
+60.6331|-151.163|60.6331|-151.163|alaska family salmon llc|
+60.6331|-151.163|60.6331|-151.163|p a s inc|
+60.6331|-151.163|60.6331|-151.163|unocal corporation|
+60.5552|-151.25|60.5552|-151.25|2go|
+60.5601|-151.287|60.5601|-151.287|2go|
+60.6379|-151.351|60.6379|-151.351|2go|
+60.6331|-151.163|60.6331|-151.163|m a p crude petroleum & natura|
+60.7411|-151.302|60.7411|-151.302|m a p crude petroleum & naturl|
+60.6331|-151.163|60.6331|-151.163|shell|
+60.6331|-151.163|60.6331|-151.163|tesoro|
+60.5011|-151.275|60.5011|-151.275|trail lakes hatchery|
+61.5724|-149.445|61.5724|-149.445|kathleen c barron|
+61.6141|-149.457|61.6141|-149.457|barton electric|
+61.5641|-149.352|61.5641|-149.352|baxter inc|
+61.6041|-149.641|61.6041|-149.641|bear|
+61.5701|-149.497|61.5701|-149.497|bear air|
+61.6253|-149.432|61.6253|-149.432|bear paw masonry|
+61.5821|-149.438|61.5821|-149.438|bears den restaurant|
+61.7321|-150.12|61.7321|-150.12|beautiful homes by jeremy|
+61.5531|-149.651|61.5531|-149.651|becky's kettle korn|
+61.5368|-149.457|61.5368|-149.457|bee teddybear ranch|
+61.5846|-149.352|61.5846|-149.352|beehive beauty shop|
+61.5841|-149.466|61.5841|-149.466|bench transmission & gear|
+61.5812|-149.448|61.5812|-149.448|benefits consulting svc|
+61.6202|-149.381|61.6202|-149.381|berg development inc|
+61.5595|-149.514|61.5595|-149.514|berg masonry|
+61.5858|-149.493|61.5858|-149.493|berg roofing|
+61.7321|-150.12|61.7321|-150.12|beryozava elementary school|
+61.5257|-149.496|61.5257|-149.496|besse engineering|
+61.5811|-149.433|61.5811|-149.433|best in the land realty & ins|
+61.5775|-149.483|61.5775|-149.483|best western inn|
+61.5531|-149.651|61.5531|-149.651|better building concepts|
+61.5895|-149.406|61.5895|-149.406|natalie beyeler do|
+61.6141|-149.457|61.6141|-149.457|big bad wolf custom builders|
+61.5811|-149.45|61.5811|-149.45|big boys toys storage|
+61.5811|-149.45|61.5811|-149.45|big lake baptist church|
+61.6141|-149.457|61.6141|-149.457|big lake lions club|
+61.5671|-149.314|61.5671|-149.314|big lake polaris|
+61.6081|-149.3|61.6081|-149.3|big valley trucking|
+61.5411|-149.588|61.5411|-149.588|birch grove studios|
+61.3981|-149.843|61.3981|-149.843|birch harbor baptist church|
+61.5901|-149.444|61.5901|-149.444|birches|
+61.6141|-149.457|61.6141|-149.457|bit o lab kennels|
+61.5855|-149.327|61.5855|-149.327|blaine's picture framing|
+61.5952|-149.377|61.5952|-149.377|blind store|
+61.6091|-149.77|61.6091|-149.77|blizzard plows of alaska|
+61.5777|-149.412|61.5777|-149.412|blockbuster video|
+61.1991|-149.903|61.1991|-149.903|foster grandparent programs|
+61.2174|-149.904|61.2174|-149.904|foster pepper rubini & reeves|
+61.1878|-149.914|61.1878|-149.914|fountain chevron|
+61.2158|-149.881|61.2158|-149.881|fountains condominium|
+61.1991|-149.903|61.1991|-149.903|four a's|
+61.1811|-149.896|61.1811|-149.896|four dam pool power agency|
+61.2171|-149.771|61.2171|-149.771|four seasons|
+61.0893|-149.811|61.0893|-149.811|four seasons masonry|
+61.1261|-149.948|61.1261|-149.948|four seasons roofing|
+61.1088|-149.84|61.1088|-149.84|four seasons sunrooms|
+61.2031|-149.749|61.2031|-149.749|four seasons travel|
+61.1282|-149.847|61.1282|-149.847|four sons construction|
+61.1201|-149.89|61.1201|-149.89|four waters aquatics|
+61.2001|-149.867|61.2001|-149.867|fourth & feather product|
+61.2188|-149.896|61.2188|-149.896|fourth avenue barber shop|
+61.2183|-149.894|61.2183|-149.894|fourth avenue trolley tours|
+61.1836|-149.796|61.1836|-149.796|fowler & assoc|
+61.2141|-149.888|61.2141|-149.888|fowler agency|
+61.1088|-149.783|61.1088|-149.783|fowler gun & machine shop|
+61.1901|-149.892|61.1901|-149.892|michael fowler|
+61.2031|-149.749|61.2031|-149.749|foxie roxies|
+61.1536|-149.884|61.1536|-149.884|foxwood condominiums|
+61.1381|-149.844|61.1381|-149.844|frame cache|
+61.1938|-149.878|61.1938|-149.878|frame of mind|
+61.1883|-149.896|61.1883|-149.896|frame workshop & gallery|
+61.0939|-149.818|61.0939|-149.818|framemaker|
+61.1955|-149.878|61.1955|-149.878|frames etc|
+61.1883|-149.894|61.1883|-149.894|frameworks|
+61.199|-149.9|61.199|-149.9|framewright|
+61.1851|-149.934|61.1851|-149.934|fran's place bed & breakfast|
+61.1973|-149.748|61.1973|-149.748|francis gallela & assoc|
+61.1715|-149.9|61.1715|-149.9|frank flavin photography|
+61.2201|-149.895|61.2201|-149.895|frank s kozoil law offices|
+61.1101|-149.857|61.1101|-149.857|a & g enterprises inc|
+61.1101|-149.857|61.1101|-149.857|c & v backhoe service|
+61.1101|-149.857|61.1101|-149.857|s & a enterprises|
+61.1101|-149.857|61.1101|-149.857|x alaska inc|
+61.1101|-149.857|61.1101|-149.857|mc kinley landscaping inc|
+61.1101|-149.857|61.1101|-149.857|cats eye excavating inc|
+61.1101|-149.857|61.1101|-149.857|kincaid & son construction co|
+61.1101|-149.857|61.1101|-149.857|wood & beek contracting inc|
+61.1101|-149.857|61.1101|-149.857|fish alaska publication llc|
+61.1101|-149.857|61.1101|-149.857|instructional resources co|
+61.1101|-149.857|61.1101|-149.857|alpha fur dressing inc|
+61.1101|-149.857|61.1101|-149.857|alaskan quality log homes|
+61.1045|-149.859|61.1045|-149.859|titan enterprises|
+61.131|-149.878|61.131|-149.878|speedy auto glass|
+61.1024|-149.853|61.1024|-149.853|kenny withrow|
+61.1097|-149.881|61.1097|-149.881|alaskan paving & cnstr co|
+61.1314|-149.862|61.1314|-149.862|advanced industries|
+61.117|-149.879|61.117|-149.879|c cohn fur processors|
+61.145|-149.878|61.145|-149.878|alaskamen magazine inc|
+61.1215|-149.926|61.1215|-149.926|wood n things|
+61.1426|-149.877|61.1426|-149.877|tweedie douglas marketing|
+61.1377|-149.864|61.1377|-149.864|grizzly advertising spc|
+61.1444|-149.867|61.1444|-149.867|lees embroidery|
+61.126|-149.934|61.126|-149.934|labau frest rsurces consulting|
+61.1407|-149.887|61.1407|-149.887|m&l landscaping|
+61.1444|-149.876|61.1444|-149.876|bridgettes dog grooming|
+61.1074|-149.862|61.1074|-149.862|alpine animalhospital|
+61.107|-149.862|61.107|-149.862|evergreen landscaping inc|
+61.1053|-149.86|61.1053|-149.86|great alaska lawn and ldscpg|
+61.1124|-149.862|61.1124|-149.862|karin e schmidt dvm|
+61.1377|-149.864|61.1377|-149.864|pet xpress/the dog wash|
+61.1293|-149.862|61.1293|-149.862|amd enterprises|
+61.1426|-149.897|61.1426|-149.897|chaluka corp|
+64.8421|-147.733|64.8421|-147.733|workers' compensation conslnt|
+64.8579|-147.77|64.8579|-147.77|works creative catering|
+64.8411|-147.718|64.8411|-147.718|world eskimo-indian olympics|
+64.8429|-147.716|64.8429|-147.716|world plus inc|
+64.8523|-147.769|64.8523|-147.769|world wide movers inc|
+64.8081|-147.851|64.8081|-147.851|wright air svc|
+64.9401|-147.402|64.9401|-147.402|wsa alaska|
+64.9039|-147.623|64.9039|-147.623|wsi certified web solutions|
+64.8132|-147.7|64.8132|-147.7|wtw trucking|
+64.8452|-147.714|64.8452|-147.714|wyatt enterprises|
+64.8916|-147.563|64.8916|-147.563|wynfromere farms|
+64.8132|-147.731|64.8132|-147.731|x-ray motors|
+64.8495|-147.716|64.8495|-147.716|xavier hall|
+64.8371|-147.716|64.8371|-147.716|xentrix dezinz|
+64.8471|-147.706|64.8471|-147.706|xerox corp|
+64.8169|-147.779|64.8169|-147.779|xral laboratories|
+64.8438|-147.901|64.8438|-147.901|yak estates apartments|
+64.843|-147.722|64.843|-147.722|leslie yamamoto|
+64.8421|-147.686|64.8421|-147.686|dale yoder|
+64.8372|-147.809|64.8372|-147.809|you're special flowers & gifts|
+64.8465|-147.74|64.8465|-147.74|young learners preschool|
+64.8199|-147.737|64.8199|-147.737|young life|
+64.8191|-147.696|64.8191|-147.696|young's cleaning svc|
+64.8127|-147.745|64.8127|-147.745|young's gear inc|
+64.8344|-147.762|64.8344|-147.762|youth facility juvenile prbtn|
+64.8419|-147.722|64.8419|-147.722|youth sports bingo|
+64.8926|-147.465|64.8926|-147.465|youth with a mission|
+64.824|-147.899|64.824|-147.899|yukon air svc|
+64.8296|-147.848|64.8296|-147.848|yukon koyukuk school district|
+64.842|-147.721|64.842|-147.721|yukon quest cache|
+64.8455|-147.696|64.8455|-147.696|yukon quest intl|
+64.8448|-147.714|64.8448|-147.714|yukon river intl tribal wtrshd|
+64.8331|-147.812|64.8331|-147.812|yukon services|
+60.5011|-151.275|60.5011|-151.275|tutka hatchery|
+60.6331|-151.163|60.6331|-151.163|eklutna salmon hatchery|
+60.5555|-151.249|60.5555|-151.249|unocal corporation|
+60.6331|-151.163|60.6331|-151.163|industrial refuse|
+60.564|-151.242|60.564|-151.242|industrial instrument service|
+60.6331|-151.163|60.6331|-151.163|alaska pipe rcvery specialists|
+60.6331|-151.163|60.6331|-151.163|arc tech services|
+60.5643|-151.195|60.5643|-151.195|cornerstone construction|
+60.6331|-151.163|60.6331|-151.163|holt construction|
+60.6742|-151.213|60.6742|-151.213|alaskan new home builders|
+60.6331|-151.163|60.6331|-151.163|jc bookey excavating|
+60.6331|-151.163|60.6331|-151.163|lalasa kennels|
+60.5619|-151.277|60.5619|-151.277|herb fireweed garden & gifts|
+60.5559|-151.262|60.5559|-151.262|groomingdales|
+60.6331|-151.163|60.6331|-151.163|moores landscaping|
+60.5569|-151.059|60.5569|-151.059|d&n landscaping|
+60.6331|-151.163|60.6331|-151.163|fv cape spencer|
+60.6331|-151.163|60.6331|-151.163|efta commercial fishing|
+60.6331|-151.163|60.6331|-151.163|evergreen alaska inc|
+54.9801|-162.099|54.9801|-162.099|peter pan seafoods inc|
+54.9801|-162.099|54.9801|-162.099|dream girl owners fv mac|
+58.7051|-156.633|58.7051|-156.633|king salmon ground service|
+58.7051|-156.633|58.7051|-156.633|odw & son construction|
+58.7051|-156.633|58.7051|-156.633|badger electric|
+58.7051|-156.633|58.7051|-156.633|harris electric inc|
+58.7051|-156.633|58.7051|-156.633|ram rentals|
+58.7051|-156.633|58.7051|-156.633|national park svcs dept intr|
+58.7051|-156.633|58.7051|-156.633|diane woods greenhouse|
+58.7051|-156.633|58.7051|-156.633|lone wolf construction|
+58.7051|-156.633|58.7051|-156.633|iliamna lake contractors llc|
+57.8591|-152.679|57.8591|-152.679|custom builders|
+57.7891|-152.397|57.7891|-152.397|kiewit pacific co|
+57.8591|-152.679|57.8591|-152.679|l g schneider & sons inc|
+57.8591|-152.679|57.8591|-152.679|f & r inc|
+57.8591|-152.679|57.8591|-152.679|majdic & son inc|
+61.5812|-149.436|61.5812|-149.436|blockbuster video|
+61.5825|-149.429|61.5825|-149.429|blood bank of alaska inc|
+61.6104|-149.425|61.6104|-149.425|bluestreak enterprises|
+61.6106|-149.392|61.6106|-149.392|bob mann appraisal svc|
+61.5803|-149.534|61.5803|-149.534|bob'sleds of alaska|
+61.5856|-149.316|61.5856|-149.316|body's in motion dance apparel|
+61.5887|-149.407|61.5887|-149.407|bogard dental|
+61.6141|-149.449|61.6141|-149.449|bogard mail svc|
+61.6144|-149.326|61.6144|-149.326|bogard mail svc|
+61.6141|-149.457|61.6141|-149.457|bogard road baptist|
+61.6141|-149.457|61.6141|-149.457|jack bohnert|
+61.6141|-149.457|61.6141|-149.457|bolinder excavating|
+61.6141|-149.457|61.6141|-149.457|bonny masonry|
+61.5824|-149.46|61.5824|-149.46|books inc|
+61.5531|-149.651|61.5531|-149.651|bootleg electric|
+61.6091|-149.77|61.6091|-149.77|borealis beach club|
+61.6141|-149.457|61.6141|-149.457|borealis property svc|
+61.7321|-150.12|61.7321|-150.12|borough transfer site|
+61.6118|-149.444|61.6118|-149.444|bowker mechanical|
+61.5825|-149.429|61.5825|-149.429|boyer bowers & tegeler|
+61.5811|-149.43|61.5811|-149.43|boyer bowers & tegeler|
+61.6006|-149.357|61.6006|-149.357|boys & girls clubs|
+61.7321|-150.12|61.7321|-150.12|brain garden|
+61.6141|-149.457|61.6141|-149.457|branching out|
+61.5867|-149.43|61.5867|-149.43|brett memorial ice arena|
+61.5869|-149.428|61.5869|-149.428|brett memorial ice arena|
+61.5776|-149.411|61.5776|-149.411|brew bakers espresso|
+61.6141|-149.457|61.6141|-149.457|bridgestone bookkeeping svc|
+61.6141|-149.457|61.6141|-149.457|brite learning materials|
+61.5822|-149.463|61.5822|-149.463|brown jug inc|
+61.5816|-149.452|61.5816|-149.452|brown's electrical supply|
+61.6141|-149.457|61.6141|-149.457|brown's plumbing|
+61.6141|-149.457|61.6141|-149.457|browngoetz consulting|
+61.5765|-149.407|61.5765|-149.407|bruce's street & skate|
+61.5788|-149.483|61.5788|-149.483|bruno's concrete|
+61.5801|-149.461|61.5801|-149.461|bruns concrete & construction|
+61.1901|-149.892|61.1901|-149.892|franke enterprises|
+61.1983|-149.88|61.1983|-149.88|franklin & assoc|
+61.2161|-149.876|61.2161|-149.876|franks concrete & masonry|
+61.2174|-149.888|61.2174|-149.888|fraternal order of ak troopers|
+61.1662|-149.845|61.1662|-149.845|fraternal order of eagles|
+61.1879|-149.886|61.1879|-149.886|fraud control unit|
+61.223|-149.872|61.223|-149.872|fraud control unit|
+61.1901|-149.892|61.1901|-149.892|frawner corp|
+61.159|-149.858|61.159|-149.858|fred astaire dance studio|
+61.1377|-149.864|61.1377|-149.864|fred astaire dance studio|
+61.1935|-149.804|61.1935|-149.804|fred barbee & assoc|
+61.2174|-149.888|61.2174|-149.888|fred meyer jewelers|
+61.1444|-149.867|61.1444|-149.867|fred meyer jewelers|
+61.195|-149.864|61.195|-149.864|fred meyer one stop shopping|
+61.1375|-149.916|61.1375|-149.916|fred meyer one stop shopping|
+61.1373|-149.839|61.1373|-149.839|fred meyer one stop shopping|
+61.2099|-149.737|61.2099|-149.737|fred meyer one stop shopping|
+61.1946|-149.941|61.1946|-149.941|fred walatka & assoc|
+61.1973|-149.877|61.1973|-149.877|fred's bail bonding|
+61.1541|-149.958|61.1541|-149.958|fred's towing & recovery|
+61.2188|-149.896|61.2188|-149.896|frederick h hahn law offices|
+61.2171|-149.795|61.2171|-149.795|free methodist church|
+61.1541|-149.958|61.1541|-149.958|freedom refuse|
+61.1973|-149.877|61.1973|-149.877|freedom ventures trust|
+61.2148|-149.9|61.2148|-149.9|freelance legal secretary|
+61.2099|-149.762|61.2099|-149.762|freight management svc|
+61.163|-149.859|61.163|-149.859|freightliner of alaska|
+61.2239|-149.823|61.2239|-149.823|freightliner of alaska|
+61.1896|-149.91|61.1896|-149.91|fremont transfer hair est|
+61.1923|-149.886|61.1923|-149.886|french bean|
+61.1541|-149.958|61.1541|-149.958|french consulate|
+61.1935|-149.905|61.1935|-149.905|french oven|
+61.1854|-149.928|61.1854|-149.928|french's construction|
+61.1152|-149.914|61.1152|-149.914|fresh & clean janitorial svc|
+61.1387|-149.915|61.1387|-149.915|wilson riley k dvm vet|
+61.1387|-149.915|61.1387|-149.915|james e gaarder dvm dacvo|
+61.1145|-149.876|61.1145|-149.876|d&t enterprises|
+61.1421|-149.9|61.1421|-149.9|dimond greenhouses inc|
+61.1053|-149.859|61.1053|-149.859|alaska winter gardens|
+61.1124|-149.862|61.1124|-149.862|handler corp|
+61.1441|-149.878|61.1441|-149.878|kitchels alaska guide service|
+61.1243|-149.927|61.1243|-149.927|romo equipment co|
+61.1337|-149.878|61.1337|-149.878|brooks range supply inc|
+61.1209|-149.884|61.1209|-149.884|roger hickel contracting|
+61.1084|-149.861|61.1084|-149.861|f & f construction|
+61.1426|-149.878|61.1426|-149.878|acme fence co inc|
\ No newline at end of file
diff --git a/hyracks-examples/hyracks-integration-tests/pom.xml b/hyracks-examples/hyracks-integration-tests/pom.xml
index 8ef1706..e5c2c51 100644
--- a/hyracks-examples/hyracks-integration-tests/pom.xml
+++ b/hyracks-examples/hyracks-integration-tests/pom.xml
@@ -76,6 +76,13 @@
   	</dependency>
   	<dependency>
   		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-storage-am-rtree</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
   		<artifactId>hyracks-test-support</artifactId>
   		<version>0.1.7-SNAPSHOT</version>
   		<type>jar</type>
diff --git a/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/btree/BTreeOperatorsTest.java b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/btree/BTreeOperatorsTest.java
index 3109c33..b4a1d60 100644
--- a/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/btree/BTreeOperatorsTest.java
+++ b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/btree/BTreeOperatorsTest.java
@@ -47,34 +47,38 @@
 import edu.uci.ics.hyracks.dataflow.std.misc.NullSinkOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.misc.PrinterOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.sort.ExternalSortOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeBulkLoadOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeInsertUpdateDeleteOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeOpHelperFactory;
 import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeSearchOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.IBTreeRegistryProvider;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexBulkLoadOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexInsertUpdateDeleteOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexStatsOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
-import edu.uci.ics.hyracks.test.support.TestBTreeRegistryProvider;
 import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
 import edu.uci.ics.hyracks.test.support.TestStorageManagerInterface;
+import edu.uci.ics.hyracks.test.support.TestTreeIndexRegistryProvider;
 import edu.uci.ics.hyracks.tests.integration.AbstractIntegrationTest;
 
 public class BTreeOperatorsTest extends AbstractIntegrationTest {
 	static {
-		TestStorageManagerComponentHolder.init(8192, 20);
+		TestStorageManagerComponentHolder.init(8192, 20, 20);
 	}
 
 	private IStorageManagerInterface storageManager = new TestStorageManagerInterface();
-	private IBTreeRegistryProvider btreeRegistryProvider = new TestBTreeRegistryProvider();
+	private IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider = new TestTreeIndexRegistryProvider();
+	private ITreeIndexOpHelperFactory opHelperFactory = new BTreeOpHelperFactory();
 
 	private final static SimpleDateFormat simpleDateFormat = new SimpleDateFormat(
 			"ddMMyy-hhmmssSS");
 	private final static String sep = System.getProperty("file.separator");
-	
+
 	// field, type and key declarations for primary index
 	private int primaryFieldCount = 6;
 	private ITypeTrait[] primaryTypeTraits = new ITypeTrait[primaryFieldCount];
@@ -82,16 +86,15 @@
 	private IBinaryComparatorFactory[] primaryComparatorFactories = new IBinaryComparatorFactory[primaryKeyFieldCount];
 	private TypeAwareTupleWriterFactory primaryTupleWriterFactory = new TypeAwareTupleWriterFactory(
 			primaryTypeTraits);
-	private IBTreeInteriorFrameFactory primaryInteriorFrameFactory = new NSMInteriorFrameFactory(
+	private ITreeIndexFrameFactory primaryInteriorFrameFactory = new BTreeNSMInteriorFrameFactory(
 			primaryTupleWriterFactory);
-	private IBTreeLeafFrameFactory primaryLeafFrameFactory = new NSMLeafFrameFactory(
+	private ITreeIndexFrameFactory primaryLeafFrameFactory = new BTreeNSMLeafFrameFactory(
 			primaryTupleWriterFactory);
 
 	private static String primaryBtreeName = "primary"
 			+ simpleDateFormat.format(new Date());
 	private static String primaryFileName = System
-			.getProperty("java.io.tmpdir")
-			+ sep + "nc1" + sep + primaryBtreeName;
+			.getProperty("java.io.tmpdir") + sep + primaryBtreeName;
 
 	private IFileSplitProvider primaryBtreeSplitProvider = new ConstantFileSplitProvider(
 			new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(
@@ -113,16 +116,15 @@
 	private IBinaryComparatorFactory[] secondaryComparatorFactories = new IBinaryComparatorFactory[secondaryKeyFieldCount];
 	private TypeAwareTupleWriterFactory secondaryTupleWriterFactory = new TypeAwareTupleWriterFactory(
 			secondaryTypeTraits);
-	private IBTreeInteriorFrameFactory secondaryInteriorFrameFactory = new NSMInteriorFrameFactory(
+	private ITreeIndexFrameFactory secondaryInteriorFrameFactory = new BTreeNSMInteriorFrameFactory(
 			secondaryTupleWriterFactory);
-	private IBTreeLeafFrameFactory secondaryLeafFrameFactory = new NSMLeafFrameFactory(
+	private ITreeIndexFrameFactory secondaryLeafFrameFactory = new BTreeNSMLeafFrameFactory(
 			secondaryTupleWriterFactory);
 
 	private static String secondaryBtreeName = "secondary"
 			+ simpleDateFormat.format(new Date());
 	private static String secondaryFileName = System
-			.getProperty("java.io.tmpdir")
-			+ sep + "nc1" + sep + secondaryBtreeName;
+			.getProperty("java.io.tmpdir") + sep + secondaryBtreeName;
 
 	private IFileSplitProvider secondaryBtreeSplitProvider = new ConstantFileSplitProvider(
 			new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(
@@ -197,11 +199,12 @@
 				NC1_ID);
 
 		int[] fieldPermutation = { 0, 1, 2, 4, 5, 7 };
-		BTreeBulkLoadOperatorDescriptor primaryBtreeBulkLoad = new BTreeBulkLoadOperatorDescriptor(
-				spec, storageManager, btreeRegistryProvider,
+		TreeIndexBulkLoadOperatorDescriptor primaryBtreeBulkLoad = new TreeIndexBulkLoadOperatorDescriptor(
+				spec, storageManager, treeIndexRegistryProvider,
 				primaryBtreeSplitProvider, primaryInteriorFrameFactory,
 				primaryLeafFrameFactory, primaryTypeTraits,
-				primaryComparatorFactories, fieldPermutation, 0.7f);
+				primaryComparatorFactories, fieldPermutation, 0.7f,
+				opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				primaryBtreeBulkLoad, NC1_ID);
 
@@ -216,6 +219,22 @@
 	}
 
 	@Test
+	public void showPrimaryIndexStats() throws Exception {
+		JobSpecification spec = new JobSpecification();
+
+		TreeIndexStatsOperatorDescriptor primaryStatsOp = new TreeIndexStatsOperatorDescriptor(
+				spec, storageManager, treeIndexRegistryProvider,
+				primaryBtreeSplitProvider, primaryInteriorFrameFactory,
+				primaryLeafFrameFactory, primaryTypeTraits,
+				primaryComparatorFactories, opHelperFactory);
+		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
+				primaryStatsOp, NC1_ID);
+
+		spec.addRoot(primaryStatsOp);
+		runTest(spec);
+	}
+
+	@Test
 	public void scanPrimaryIndexTest() throws Exception {
 		JobSpecification spec = new JobSpecification();
 
@@ -242,11 +261,11 @@
 		int[] highKeyFields = null; // + infinity
 
 		BTreeSearchOperatorDescriptor primaryBtreeSearchOp = new BTreeSearchOperatorDescriptor(
-				spec, primaryRecDesc, storageManager, btreeRegistryProvider,
-				primaryBtreeSplitProvider, primaryInteriorFrameFactory,
-				primaryLeafFrameFactory, primaryTypeTraits,
-				primaryComparatorFactories, true, lowKeyFields, highKeyFields,
-				true, true);
+				spec, primaryRecDesc, storageManager,
+				treeIndexRegistryProvider, primaryBtreeSplitProvider,
+				primaryInteriorFrameFactory, primaryLeafFrameFactory,
+				primaryTypeTraits, primaryComparatorFactories, true,
+				lowKeyFields, highKeyFields, true, true, opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				primaryBtreeSearchOp, NC1_ID);
 
@@ -295,11 +314,11 @@
 		int[] highKeyFields = { 1 };
 
 		BTreeSearchOperatorDescriptor primaryBtreeSearchOp = new BTreeSearchOperatorDescriptor(
-				spec, primaryRecDesc, storageManager, btreeRegistryProvider,
-				primaryBtreeSplitProvider, primaryInteriorFrameFactory,
-				primaryLeafFrameFactory, primaryTypeTraits,
-				primaryComparatorFactories, true, lowKeyFields, highKeyFields,
-				true, true);
+				spec, primaryRecDesc, storageManager,
+				treeIndexRegistryProvider, primaryBtreeSplitProvider,
+				primaryInteriorFrameFactory, primaryLeafFrameFactory,
+				primaryTypeTraits, primaryComparatorFactories, true,
+				lowKeyFields, highKeyFields, true, true, opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				primaryBtreeSearchOp, NC1_ID);
 
@@ -344,11 +363,11 @@
 
 		// scan primary index
 		BTreeSearchOperatorDescriptor primaryBtreeSearchOp = new BTreeSearchOperatorDescriptor(
-				spec, primaryRecDesc, storageManager, btreeRegistryProvider,
-				primaryBtreeSplitProvider, primaryInteriorFrameFactory,
-				primaryLeafFrameFactory, primaryTypeTraits,
-				primaryComparatorFactories, true, lowKeyFields, highKeyFields,
-				true, true);
+				spec, primaryRecDesc, storageManager,
+				treeIndexRegistryProvider, primaryBtreeSplitProvider,
+				primaryInteriorFrameFactory, primaryLeafFrameFactory,
+				primaryTypeTraits, primaryComparatorFactories, true,
+				lowKeyFields, highKeyFields, true, true, opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				primaryBtreeSearchOp, NC1_ID);
 
@@ -364,11 +383,12 @@
 
 		// load secondary index
 		int[] fieldPermutation = { 3, 0 };
-		BTreeBulkLoadOperatorDescriptor secondaryBtreeBulkLoad = new BTreeBulkLoadOperatorDescriptor(
-				spec, storageManager, btreeRegistryProvider,
+		TreeIndexBulkLoadOperatorDescriptor secondaryBtreeBulkLoad = new TreeIndexBulkLoadOperatorDescriptor(
+				spec, storageManager, treeIndexRegistryProvider,
 				secondaryBtreeSplitProvider, secondaryInteriorFrameFactory,
 				secondaryLeafFrameFactory, secondaryTypeTraits,
-				secondaryComparatorFactories, fieldPermutation, 0.7f);
+				secondaryComparatorFactories, fieldPermutation, 0.7f,
+				opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				secondaryBtreeBulkLoad, NC1_ID);
 
@@ -416,11 +436,12 @@
 
 		// search secondary index
 		BTreeSearchOperatorDescriptor secondaryBtreeSearchOp = new BTreeSearchOperatorDescriptor(
-				spec, secondaryRecDesc, storageManager, btreeRegistryProvider,
-				secondaryBtreeSplitProvider, secondaryInteriorFrameFactory,
-				secondaryLeafFrameFactory, secondaryTypeTraits,
-				secondaryComparatorFactories, true, secondaryLowKeyFields,
-				secondaryHighKeyFields, true, true);
+				spec, secondaryRecDesc, storageManager,
+				treeIndexRegistryProvider, secondaryBtreeSplitProvider,
+				secondaryInteriorFrameFactory, secondaryLeafFrameFactory,
+				secondaryTypeTraits, secondaryComparatorFactories, true,
+				secondaryLowKeyFields, secondaryHighKeyFields, true, true,
+				opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				secondaryBtreeSearchOp, NC1_ID);
 
@@ -431,11 +452,12 @@
 
 		// search primary index
 		BTreeSearchOperatorDescriptor primaryBtreeSearchOp = new BTreeSearchOperatorDescriptor(
-				spec, primaryRecDesc, storageManager, btreeRegistryProvider,
-				primaryBtreeSplitProvider, primaryInteriorFrameFactory,
-				primaryLeafFrameFactory, primaryTypeTraits,
-				primaryComparatorFactories, true, primaryLowKeyFields,
-				primaryHighKeyFields, true, true);
+				spec, primaryRecDesc, storageManager,
+				treeIndexRegistryProvider, primaryBtreeSplitProvider,
+				primaryInteriorFrameFactory, primaryLeafFrameFactory,
+				primaryTypeTraits, primaryComparatorFactories, true,
+				primaryLowKeyFields, primaryHighKeyFields, true, true,
+				opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				primaryBtreeSearchOp, NC1_ID);
 
@@ -493,23 +515,23 @@
 
 		// insert into primary index
 		int[] primaryFieldPermutation = { 0, 1, 2, 4, 5, 7 };
-		BTreeInsertUpdateDeleteOperatorDescriptor primaryBtreeInsertOp = new BTreeInsertUpdateDeleteOperatorDescriptor(
-				spec, ordersDesc, storageManager, btreeRegistryProvider,
+		TreeIndexInsertUpdateDeleteOperatorDescriptor primaryBtreeInsertOp = new TreeIndexInsertUpdateDeleteOperatorDescriptor(
+				spec, ordersDesc, storageManager, treeIndexRegistryProvider,
 				primaryBtreeSplitProvider, primaryInteriorFrameFactory,
 				primaryLeafFrameFactory, primaryTypeTraits,
 				primaryComparatorFactories, primaryFieldPermutation,
-				BTreeOp.BTO_INSERT);
+				IndexOp.INSERT, opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				primaryBtreeInsertOp, NC1_ID);
 
 		// first secondary index
 		int[] fieldPermutationB = { 4, 0 };
-		BTreeInsertUpdateDeleteOperatorDescriptor secondaryInsertOp = new BTreeInsertUpdateDeleteOperatorDescriptor(
-				spec, ordersDesc, storageManager, btreeRegistryProvider,
+		TreeIndexInsertUpdateDeleteOperatorDescriptor secondaryInsertOp = new TreeIndexInsertUpdateDeleteOperatorDescriptor(
+				spec, ordersDesc, storageManager, treeIndexRegistryProvider,
 				secondaryBtreeSplitProvider, secondaryInteriorFrameFactory,
 				secondaryLeafFrameFactory, secondaryTypeTraits,
 				secondaryComparatorFactories, fieldPermutationB,
-				BTreeOp.BTO_INSERT);
+				IndexOp.INSERT, opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				secondaryInsertOp, NC1_ID);
 
@@ -564,11 +586,12 @@
 
 		// search secondary index
 		BTreeSearchOperatorDescriptor secondaryBtreeSearchOp = new BTreeSearchOperatorDescriptor(
-				spec, secondaryRecDesc, storageManager, btreeRegistryProvider,
-				secondaryBtreeSplitProvider, secondaryInteriorFrameFactory,
-				secondaryLeafFrameFactory, secondaryTypeTraits,
-				secondaryComparatorFactories, true, secondaryLowKeyFields,
-				secondaryHighKeyFields, true, true);
+				spec, secondaryRecDesc, storageManager,
+				treeIndexRegistryProvider, secondaryBtreeSplitProvider,
+				secondaryInteriorFrameFactory, secondaryLeafFrameFactory,
+				secondaryTypeTraits, secondaryComparatorFactories, true,
+				secondaryLowKeyFields, secondaryHighKeyFields, true, true,
+				opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				secondaryBtreeSearchOp, NC1_ID);
 
@@ -579,11 +602,12 @@
 
 		// search primary index
 		BTreeSearchOperatorDescriptor primaryBtreeSearchOp = new BTreeSearchOperatorDescriptor(
-				spec, primaryRecDesc, storageManager, btreeRegistryProvider,
-				primaryBtreeSplitProvider, primaryInteriorFrameFactory,
-				primaryLeafFrameFactory, primaryTypeTraits,
-				primaryComparatorFactories, true, primaryLowKeyFields,
-				primaryHighKeyFields, true, true);
+				spec, primaryRecDesc, storageManager,
+				treeIndexRegistryProvider, primaryBtreeSplitProvider,
+				primaryInteriorFrameFactory, primaryLeafFrameFactory,
+				primaryTypeTraits, primaryComparatorFactories, true,
+				primaryLowKeyFields, primaryHighKeyFields, true, true,
+				opHelperFactory);
 		PartitionConstraintHelper.addAbsoluteLocationConstraint(spec,
 				primaryBtreeSearchOp, NC1_ID);
 
diff --git a/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/integration/TPCHCustomerOrderHashJoinTest.java b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/integration/TPCHCustomerOrderHashJoinTest.java
index db5985d..a8db325 100644
--- a/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/integration/TPCHCustomerOrderHashJoinTest.java
+++ b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/integration/TPCHCustomerOrderHashJoinTest.java
@@ -80,7 +80,15 @@
     }
 
     /*
-     * TPCH Customer table: CREATE TABLE CUSTOMER ( C_CUSTKEY INTEGER NOT NULL, C_NAME VARCHAR(25) NOT NULL, C_ADDRESS VARCHAR(40) NOT NULL, C_NATIONKEY INTEGER NOT NULL, C_PHONE CHAR(15) NOT NULL, C_ACCTBAL DECIMAL(15,2) NOT NULL, C_MKTSEGMENT CHAR(10) NOT NULL, C_COMMENT VARCHAR(117) NOT NULL ); TPCH Orders table: CREATE TABLE ORDERS ( O_ORDERKEY INTEGER NOT NULL, O_CUSTKEY INTEGER NOT NULL, O_ORDERSTATUS CHAR(1) NOT NULL, O_TOTALPRICE DECIMAL(15,2) NOT NULL, O_ORDERDATE DATE NOT NULL, O_ORDERPRIORITY CHAR(15) NOT NULL, O_CLERK CHAR(15) NOT NULL, O_SHIPPRIORITY INTEGER NOT NULL, O_COMMENT VARCHAR(79) NOT NULL );
+     * TPCH Customer table: CREATE TABLE CUSTOMER ( C_CUSTKEY INTEGER NOT NULL,
+     * C_NAME VARCHAR(25) NOT NULL, C_ADDRESS VARCHAR(40) NOT NULL, C_NATIONKEY
+     * INTEGER NOT NULL, C_PHONE CHAR(15) NOT NULL, C_ACCTBAL DECIMAL(15,2) NOT
+     * NULL, C_MKTSEGMENT CHAR(10) NOT NULL, C_COMMENT VARCHAR(117) NOT NULL );
+     * TPCH Orders table: CREATE TABLE ORDERS ( O_ORDERKEY INTEGER NOT NULL,
+     * O_CUSTKEY INTEGER NOT NULL, O_ORDERSTATUS CHAR(1) NOT NULL, O_TOTALPRICE
+     * DECIMAL(15,2) NOT NULL, O_ORDERDATE DATE NOT NULL, O_ORDERPRIORITY
+     * CHAR(15) NOT NULL, O_CLERK CHAR(15) NOT NULL, O_SHIPPRIORITY INTEGER NOT
+     * NULL, O_COMMENT VARCHAR(79) NOT NULL );
      */
 
     @Test
@@ -364,9 +372,11 @@
 
         IOperatorDescriptor printer = DEBUG ? new PrinterOperatorDescriptor(spec)
                 : new NullSinkOperatorDescriptor(spec);
-        // FileSplit[] custOrdersJoinSplits = new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(
-        //     "data/tpch0.001/custOrdersLeftOuterJoin.csv"))) };
-        // LineFileWriteOperatorDescriptor printer = new LineFileWriteOperatorDescriptor(spec, custOrdersJoinSplits);
+        // FileSplit[] custOrdersJoinSplits = new FileSplit[] { new
+        // FileSplit(NC1_ID, new FileReference(new File(
+        // "data/tpch0.001/custOrdersLeftOuterJoin.csv"))) };
+        // LineFileWriteOperatorDescriptor printer = new
+        // LineFileWriteOperatorDescriptor(spec, custOrdersJoinSplits);
         PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC1_ID);
 
         IConnectorDescriptor ordJoinConn = new OneToOneConnectorDescriptor(spec);
@@ -446,9 +456,11 @@
 
         IOperatorDescriptor printer = DEBUG ? new PrinterOperatorDescriptor(spec)
                 : new NullSinkOperatorDescriptor(spec);
-        // FileSplit[] custOrdersJoinSplits = new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(
-        //     "data/tpch0.001/custOrdersLeftOuterJoin.csv"))) };
-        // LineFileWriteOperatorDescriptor printer = new LineFileWriteOperatorDescriptor(spec, custOrdersJoinSplits);
+        // FileSplit[] custOrdersJoinSplits = new FileSplit[] { new
+        // FileSplit(NC1_ID, new FileReference(new File(
+        // "data/tpch0.001/custOrdersLeftOuterJoin.csv"))) };
+        // LineFileWriteOperatorDescriptor printer = new
+        // LineFileWriteOperatorDescriptor(spec, custOrdersJoinSplits);
         PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC1_ID);
 
         IConnectorDescriptor ordJoinConn = new OneToOneConnectorDescriptor(spec);
@@ -528,9 +540,11 @@
 
         IOperatorDescriptor printer = DEBUG ? new PrinterOperatorDescriptor(spec)
                 : new NullSinkOperatorDescriptor(spec);
-        // FileSplit[] custOrdersJoinSplits = new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(
-        //     "data/tpch0.001/custOrdersLeftOuterJoin.csv"))) };
-        // LineFileWriteOperatorDescriptor printer = new LineFileWriteOperatorDescriptor(spec, custOrdersJoinSplits);
+        // FileSplit[] custOrdersJoinSplits = new FileSplit[] { new
+        // FileSplit(NC1_ID, new FileReference(new File(
+        // "data/tpch0.001/custOrdersLeftOuterJoin.csv"))) };
+        // LineFileWriteOperatorDescriptor printer = new
+        // LineFileWriteOperatorDescriptor(spec, custOrdersJoinSplits);
         PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC1_ID);
 
         IConnectorDescriptor ordJoinConn = new OneToOneConnectorDescriptor(spec);
diff --git a/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/invertedindex/InvertedIndexOperatorsTest.java b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/invertedindex/InvertedIndexOperatorsTest.java
index 2cfe438..c84ef74 100644
--- a/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/invertedindex/InvertedIndexOperatorsTest.java
+++ b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/invertedindex/InvertedIndexOperatorsTest.java
@@ -21,9 +21,11 @@
 import edu.uci.ics.hyracks.dataflow.std.file.FileSplit;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
 import edu.uci.ics.hyracks.dataflow.std.misc.PrinterOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizerFactory;
 import edu.uci.ics.hyracks.storage.am.invertedindex.dataflow.BinaryTokenizerOperatorDescriptor;
 import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.DelimitedUTF8StringBinaryTokenizerFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizerFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.ITokenFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.UTF8WordTokenFactory;
 import edu.uci.ics.hyracks.tests.integration.AbstractIntegrationTest;
 
 public class InvertedIndexOperatorsTest extends AbstractIntegrationTest {
@@ -45,7 +47,10 @@
 
         RecordDescriptor tokenizerRecDesc = new RecordDescriptor(new ISerializerDeserializer[] {
                 UTF8StringSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE });
-        IBinaryTokenizerFactory tokenizerFactory = new DelimitedUTF8StringBinaryTokenizerFactory(' ');
+
+        ITokenFactory tokenFactory = new UTF8WordTokenFactory();
+        IBinaryTokenizerFactory tokenizerFactory = new DelimitedUTF8StringBinaryTokenizerFactory(true, false,
+                tokenFactory);
         int[] tokenFields = { 1 };
         int[] projFields = { 0 };
         BinaryTokenizerOperatorDescriptor binaryTokenizer = new BinaryTokenizerOperatorDescriptor(spec,
diff --git a/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/rtree/RTreeOperatorsTest.java b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/rtree/RTreeOperatorsTest.java
new file mode 100644
index 0000000..5f6eb3a
--- /dev/null
+++ b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/rtree/RTreeOperatorsTest.java
@@ -0,0 +1,431 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.tests.rtree;
+
+import java.io.DataOutput;
+import java.io.File;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.api.constraints.PartitionConstraintHelper;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.dataflow.value.TypeTrait;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.api.job.JobSpecification;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.DoubleBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.UTF8StringBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.DoubleSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.parsers.DoubleParserFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.parsers.IValueParserFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.parsers.UTF8StringParserFactory;
+import edu.uci.ics.hyracks.dataflow.std.connectors.OneToOneConnectorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.file.ConstantFileSplitProvider;
+import edu.uci.ics.hyracks.dataflow.std.file.DelimitedDataTupleParserFactory;
+import edu.uci.ics.hyracks.dataflow.std.file.FileScanOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.file.FileSplit;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.dataflow.std.misc.ConstantTupleSourceOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.misc.PrinterOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.sort.ExternalSortOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeSearchOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexBulkLoadOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexStatsOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.dataflow.RTreeOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.dataflow.RTreeSearchOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.tuples.RTreeTypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
+import edu.uci.ics.hyracks.test.support.TestStorageManagerInterface;
+import edu.uci.ics.hyracks.test.support.TestTreeIndexRegistryProvider;
+import edu.uci.ics.hyracks.tests.integration.AbstractIntegrationTest;
+
+public class RTreeOperatorsTest extends AbstractIntegrationTest {
+    static {
+        TestStorageManagerComponentHolder.init(8192, 20, 20);
+    }
+
+    private IStorageManagerInterface storageManager = new TestStorageManagerInterface();
+    private IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider = new TestTreeIndexRegistryProvider();
+    private ITreeIndexOpHelperFactory opHelperFactory = new RTreeOpHelperFactory();
+    private ITreeIndexOpHelperFactory bTreeopHelperFactory = new BTreeOpHelperFactory();
+
+    private final static SimpleDateFormat simpleDateFormat = new SimpleDateFormat("ddMMyy-hhmmssSS");
+    private final static String sep = System.getProperty("file.separator");
+
+    // field, type and key declarations for primary R-tree index
+    private int primaryFieldCount = 5;
+    private int primaryKeyFieldCount = 4;
+    private ITypeTrait[] primaryTypeTraits = new ITypeTrait[primaryFieldCount];
+    private IBinaryComparatorFactory[] primaryComparatorFactories = new IBinaryComparatorFactory[primaryKeyFieldCount];
+
+    private RTreeTypeAwareTupleWriterFactory primaryTupleWriterFactory = new RTreeTypeAwareTupleWriterFactory(
+            primaryTypeTraits);
+    private ITreeIndexFrameFactory primaryInteriorFrameFactory = new RTreeNSMInteriorFrameFactory(
+            primaryTupleWriterFactory, primaryKeyFieldCount);
+    private ITreeIndexFrameFactory primaryLeafFrameFactory = new RTreeNSMLeafFrameFactory(primaryTupleWriterFactory,
+            primaryKeyFieldCount);
+
+    private static String primaryRTreeName = "primary" + simpleDateFormat.format(new Date());
+    private static String primaryFileName = System.getProperty("java.io.tmpdir") + sep + primaryRTreeName;
+
+    private IFileSplitProvider primaryRTreeSplitProvider = new ConstantFileSplitProvider(
+            new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(primaryFileName))) });
+
+    private RecordDescriptor primaryRecDesc = new RecordDescriptor(new ISerializerDeserializer[] {
+            DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+            DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+            UTF8StringSerializerDeserializer.INSTANCE });
+
+    // field, type and key declarations for primary B-tree index
+    private int primaryBTreeFieldCount = 10;
+    private ITypeTrait[] primaryBTreeTypeTraits = new ITypeTrait[primaryBTreeFieldCount];
+    private int primaryBTreeKeyFieldCount = 1;
+    private IBinaryComparatorFactory[] primaryBTreeComparatorFactories = new IBinaryComparatorFactory[primaryBTreeKeyFieldCount];
+    private TypeAwareTupleWriterFactory primaryBTreeTupleWriterFactory = new TypeAwareTupleWriterFactory(
+            primaryBTreeTypeTraits);
+    private ITreeIndexFrameFactory primaryBTreeInteriorFrameFactory = new BTreeNSMInteriorFrameFactory(
+            primaryBTreeTupleWriterFactory);
+    private ITreeIndexFrameFactory primaryBTreeLeafFrameFactory = new BTreeNSMLeafFrameFactory(
+            primaryBTreeTupleWriterFactory);
+
+    private static String primaryBTreeName = "primaryBTree" + simpleDateFormat.format(new Date());
+    private static String primaryBTreeFileName = System.getProperty("java.io.tmpdir") + sep + primaryBTreeName;
+
+    private IFileSplitProvider primaryBTreeSplitProvider = new ConstantFileSplitProvider(
+            new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(primaryBTreeFileName))) });
+
+    private RecordDescriptor primaryBTreeRecDesc = new RecordDescriptor(new ISerializerDeserializer[] {
+            UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+            UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+            UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+            DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+            DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE, });
+
+    // field, type and key declarations for secondary indexes
+    private int secondaryFieldCount = 5;
+    private ITypeTrait[] secondaryTypeTraits = new ITypeTrait[secondaryFieldCount];
+    private int secondaryKeyFieldCount = 4;
+    private IBinaryComparatorFactory[] secondaryComparatorFactories = new IBinaryComparatorFactory[secondaryKeyFieldCount];
+    private RTreeTypeAwareTupleWriterFactory secondaryTupleWriterFactory = new RTreeTypeAwareTupleWriterFactory(
+            secondaryTypeTraits);
+    private ITreeIndexFrameFactory secondaryInteriorFrameFactory = new RTreeNSMInteriorFrameFactory(
+            secondaryTupleWriterFactory, secondaryKeyFieldCount);
+    private ITreeIndexFrameFactory secondaryLeafFrameFactory = new RTreeNSMLeafFrameFactory(
+            secondaryTupleWriterFactory, secondaryKeyFieldCount);
+
+    private static String secondaryRTreeName = "secondary" + simpleDateFormat.format(new Date());
+    private static String secondaryFileName = System.getProperty("java.io.tmpdir") + sep + secondaryRTreeName;
+
+    private IFileSplitProvider secondaryRTreeSplitProvider = new ConstantFileSplitProvider(
+            new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(secondaryFileName))) });
+
+    private RecordDescriptor secondaryRecDesc = new RecordDescriptor(new ISerializerDeserializer[] {
+            DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+            DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+            UTF8StringSerializerDeserializer.INSTANCE });
+
+    @Before
+    public void setup() {
+        // field, type and key declarations for primary R-tree index
+        primaryTypeTraits[0] = new TypeTrait(8);
+        primaryTypeTraits[1] = new TypeTrait(8);
+        primaryTypeTraits[2] = new TypeTrait(8);
+        primaryTypeTraits[3] = new TypeTrait(8);
+        primaryTypeTraits[4] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        primaryComparatorFactories[0] = DoubleBinaryComparatorFactory.INSTANCE;
+        primaryComparatorFactories[1] = primaryComparatorFactories[0];
+        primaryComparatorFactories[2] = primaryComparatorFactories[0];
+        primaryComparatorFactories[3] = primaryComparatorFactories[0];
+
+        // field, type and key declarations for primary B-tree index
+        primaryBTreeTypeTraits[0] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        primaryBTreeTypeTraits[1] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        primaryBTreeTypeTraits[2] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        primaryBTreeTypeTraits[3] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        primaryBTreeTypeTraits[4] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        primaryBTreeTypeTraits[5] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        primaryBTreeTypeTraits[6] = new TypeTrait(8);
+        primaryBTreeTypeTraits[7] = new TypeTrait(8);
+        primaryBTreeTypeTraits[8] = new TypeTrait(8);
+        primaryBTreeTypeTraits[9] = new TypeTrait(8);
+        primaryBTreeComparatorFactories[0] = UTF8StringBinaryComparatorFactory.INSTANCE;
+
+        // field, type and key declarations for secondary indexes
+        secondaryTypeTraits[0] = new TypeTrait(8);
+        secondaryTypeTraits[1] = new TypeTrait(8);
+        secondaryTypeTraits[2] = new TypeTrait(8);
+        secondaryTypeTraits[3] = new TypeTrait(8);
+        secondaryTypeTraits[4] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        secondaryComparatorFactories[0] = DoubleBinaryComparatorFactory.INSTANCE;
+        secondaryComparatorFactories[1] = secondaryComparatorFactories[0];
+        secondaryComparatorFactories[2] = secondaryComparatorFactories[0];
+        secondaryComparatorFactories[3] = secondaryComparatorFactories[0];
+    }
+
+    @Test
+    public void loadPrimaryBTreeIndexTest() throws Exception {
+        JobSpecification spec = new JobSpecification();
+
+        FileSplit[] ordersSplits = new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(
+                "data/orders-with-locations.txt"))) };
+        IFileSplitProvider ordersSplitProvider = new ConstantFileSplitProvider(ordersSplits);
+        RecordDescriptor ordersDesc = new RecordDescriptor(new ISerializerDeserializer[] {
+                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+                UTF8StringSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE });
+
+        FileScanOperatorDescriptor ordScanner = new FileScanOperatorDescriptor(spec, ordersSplitProvider,
+                new DelimitedDataTupleParserFactory(new IValueParserFactory[] { UTF8StringParserFactory.INSTANCE,
+                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
+                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
+                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
+                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
+                        DoubleParserFactory.INSTANCE, DoubleParserFactory.INSTANCE, DoubleParserFactory.INSTANCE,
+                        DoubleParserFactory.INSTANCE }, '|'), ordersDesc);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, ordScanner, NC1_ID);
+
+        ExternalSortOperatorDescriptor sorter = new ExternalSortOperatorDescriptor(spec, 1000, new int[] { 0 },
+                new IBinaryComparatorFactory[] { UTF8StringBinaryComparatorFactory.INSTANCE }, ordersDesc);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, sorter, NC1_ID);
+
+        int[] fieldPermutation = { 0, 1, 2, 4, 5, 7, 9, 10, 11, 12 };
+        TreeIndexBulkLoadOperatorDescriptor primaryBTreeBulkLoad = new TreeIndexBulkLoadOperatorDescriptor(spec,
+                storageManager, treeIndexRegistryProvider, primaryBTreeSplitProvider, primaryBTreeInteriorFrameFactory,
+                primaryBTreeLeafFrameFactory, primaryBTreeTypeTraits, primaryBTreeComparatorFactories,
+                fieldPermutation, 0.7f, bTreeopHelperFactory);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, primaryBTreeBulkLoad, NC1_ID);
+
+        spec.connect(new OneToOneConnectorDescriptor(spec), ordScanner, 0, sorter, 0);
+
+        spec.connect(new OneToOneConnectorDescriptor(spec), sorter, 0, primaryBTreeBulkLoad, 0);
+
+        spec.addRoot(primaryBTreeBulkLoad);
+        runTest(spec);
+    }
+
+    @Test
+    public void loadPrimaryIndexTest() throws Exception {
+        JobSpecification spec = new JobSpecification();
+
+        FileSplit[] objectsSplits = new FileSplit[] { new FileSplit(NC1_ID, new FileReference(new File(
+                "data/spatial.txt"))) };
+        IFileSplitProvider objectsSplitProvider = new ConstantFileSplitProvider(objectsSplits);
+        RecordDescriptor objectsDesc = new RecordDescriptor(new ISerializerDeserializer[] {
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                UTF8StringSerializerDeserializer.INSTANCE });
+
+        FileScanOperatorDescriptor objScanner = new FileScanOperatorDescriptor(spec, objectsSplitProvider,
+                new DelimitedDataTupleParserFactory(new IValueParserFactory[] { DoubleParserFactory.INSTANCE,
+                        DoubleParserFactory.INSTANCE, DoubleParserFactory.INSTANCE, DoubleParserFactory.INSTANCE,
+                        UTF8StringParserFactory.INSTANCE }, '|'), objectsDesc);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, objScanner, NC1_ID);
+
+        int[] fieldPermutation = { 0, 1, 2, 3, 4 };
+        TreeIndexBulkLoadOperatorDescriptor primaryRTreeBulkLoad = new TreeIndexBulkLoadOperatorDescriptor(spec,
+                storageManager, treeIndexRegistryProvider, primaryRTreeSplitProvider, primaryInteriorFrameFactory,
+                primaryLeafFrameFactory, primaryTypeTraits, primaryComparatorFactories, fieldPermutation, 0.7f,
+                opHelperFactory);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, primaryRTreeBulkLoad, NC1_ID);
+
+        spec.connect(new OneToOneConnectorDescriptor(spec), objScanner, 0, primaryRTreeBulkLoad, 0);
+
+        spec.addRoot(primaryRTreeBulkLoad);
+        runTest(spec);
+    }
+
+    @Test
+    public void loadSecondaryIndexTest() throws Exception {
+        JobSpecification spec = new JobSpecification();
+
+        // build dummy tuple containing nothing
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(primaryKeyFieldCount * 2);
+        DataOutput dos = tb.getDataOutput();
+
+        tb.reset();
+        UTF8StringSerializerDeserializer.INSTANCE.serialize("0", dos);
+        tb.addFieldEndOffset();
+
+        ISerializerDeserializer[] keyRecDescSers = { UTF8StringSerializerDeserializer.INSTANCE,
+                UTF8StringSerializerDeserializer.INSTANCE };
+        RecordDescriptor keyRecDesc = new RecordDescriptor(keyRecDescSers);
+
+        ConstantTupleSourceOperatorDescriptor keyProviderOp = new ConstantTupleSourceOperatorDescriptor(spec,
+                keyRecDesc, tb.getFieldEndOffsets(), tb.getByteArray(), tb.getSize());
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, keyProviderOp, NC1_ID);
+
+        int[] lowKeyFields = null; // - infinity
+        int[] highKeyFields = null; // + infinity
+
+        // scan primary index
+        BTreeSearchOperatorDescriptor primaryBTreeSearchOp = new BTreeSearchOperatorDescriptor(spec,
+                primaryBTreeRecDesc, storageManager, treeIndexRegistryProvider, primaryBTreeSplitProvider,
+                primaryBTreeInteriorFrameFactory, primaryBTreeLeafFrameFactory, primaryBTreeTypeTraits,
+                primaryBTreeComparatorFactories, true, lowKeyFields, highKeyFields, true, true, opHelperFactory);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, primaryBTreeSearchOp, NC1_ID);
+
+        // load secondary index
+        int[] fieldPermutation = { 6, 7, 8, 9, 0 };
+        TreeIndexBulkLoadOperatorDescriptor secondaryRTreeBulkLoad = new TreeIndexBulkLoadOperatorDescriptor(spec,
+                storageManager, treeIndexRegistryProvider, secondaryRTreeSplitProvider, secondaryInteriorFrameFactory,
+                secondaryLeafFrameFactory, secondaryTypeTraits, secondaryComparatorFactories, fieldPermutation, 0.7f,
+                opHelperFactory);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, secondaryRTreeBulkLoad, NC1_ID);
+
+        spec.connect(new OneToOneConnectorDescriptor(spec), keyProviderOp, 0, primaryBTreeSearchOp, 0);
+        spec.connect(new OneToOneConnectorDescriptor(spec), primaryBTreeSearchOp, 0, secondaryRTreeBulkLoad, 0);
+
+        spec.addRoot(secondaryRTreeBulkLoad);
+        runTest(spec);
+    }
+
+    @Test
+    public void showPrimaryIndexStats() throws Exception {
+        JobSpecification spec = new JobSpecification();
+
+        TreeIndexStatsOperatorDescriptor primaryStatsOp = new TreeIndexStatsOperatorDescriptor(spec, storageManager,
+                treeIndexRegistryProvider, primaryRTreeSplitProvider, primaryInteriorFrameFactory,
+                primaryLeafFrameFactory, primaryTypeTraits, primaryComparatorFactories, opHelperFactory);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, primaryStatsOp, NC1_ID);
+
+        spec.addRoot(primaryStatsOp);
+        runTest(spec);
+    }
+
+    @Test
+    public void searchPrimaryIndexTest() throws Exception {
+        JobSpecification spec = new JobSpecification();
+
+        // build tuple
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(primaryKeyFieldCount);
+        DataOutput dos = tb.getDataOutput();
+
+        tb.reset();
+        DoubleSerializerDeserializer.INSTANCE.serialize(61.2894, dos);
+        tb.addFieldEndOffset();
+        DoubleSerializerDeserializer.INSTANCE.serialize(-149.624, dos);
+        tb.addFieldEndOffset();
+        DoubleSerializerDeserializer.INSTANCE.serialize(61.8894, dos);
+        tb.addFieldEndOffset();
+        DoubleSerializerDeserializer.INSTANCE.serialize(-149.024, dos);
+        tb.addFieldEndOffset();
+
+        ISerializerDeserializer[] keyRecDescSers = { DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE };
+        RecordDescriptor keyRecDesc = new RecordDescriptor(keyRecDescSers);
+
+        ConstantTupleSourceOperatorDescriptor keyProviderOp = new ConstantTupleSourceOperatorDescriptor(spec,
+                keyRecDesc, tb.getFieldEndOffsets(), tb.getByteArray(), tb.getSize());
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, keyProviderOp, NC1_ID);
+
+        int[] keyFields = { 0, 1, 2, 3 };
+
+        RTreeSearchOperatorDescriptor primaryRTreeSearchOp = new RTreeSearchOperatorDescriptor(spec, primaryRecDesc,
+                storageManager, treeIndexRegistryProvider, primaryRTreeSplitProvider, primaryInteriorFrameFactory,
+                primaryLeafFrameFactory, primaryTypeTraits, primaryComparatorFactories, keyFields, opHelperFactory);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, primaryRTreeSearchOp, NC1_ID);
+
+        PrinterOperatorDescriptor printer = new PrinterOperatorDescriptor(spec);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC1_ID);
+
+        spec.connect(new OneToOneConnectorDescriptor(spec), keyProviderOp, 0, primaryRTreeSearchOp, 0);
+        spec.connect(new OneToOneConnectorDescriptor(spec), primaryRTreeSearchOp, 0, printer, 0);
+
+        spec.addRoot(printer);
+        runTest(spec);
+    }
+
+    @Test
+    public void searchSecondaryIndexTest() throws Exception {
+        JobSpecification spec = new JobSpecification();
+
+        // build tuple
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(secondaryKeyFieldCount);
+        DataOutput dos = tb.getDataOutput();
+
+        tb.reset();
+        DoubleSerializerDeserializer.INSTANCE.serialize(61.2894, dos);
+        tb.addFieldEndOffset();
+        DoubleSerializerDeserializer.INSTANCE.serialize(-149.624, dos);
+        tb.addFieldEndOffset();
+        DoubleSerializerDeserializer.INSTANCE.serialize(61.8894, dos);
+        tb.addFieldEndOffset();
+        DoubleSerializerDeserializer.INSTANCE.serialize(-149.024, dos);
+        tb.addFieldEndOffset();
+
+        ISerializerDeserializer[] keyRecDescSers = { DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE };
+        RecordDescriptor keyRecDesc = new RecordDescriptor(keyRecDescSers);
+
+        ConstantTupleSourceOperatorDescriptor keyProviderOp = new ConstantTupleSourceOperatorDescriptor(spec,
+                keyRecDesc, tb.getFieldEndOffsets(), tb.getByteArray(), tb.getSize());
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, keyProviderOp, NC1_ID);
+
+        int[] keyFields = { 0, 1, 2, 3 };
+
+        RTreeSearchOperatorDescriptor secondaryRTreeSearchOp = new RTreeSearchOperatorDescriptor(spec,
+                secondaryRecDesc, storageManager, treeIndexRegistryProvider, secondaryRTreeSplitProvider,
+                secondaryInteriorFrameFactory, secondaryLeafFrameFactory, secondaryTypeTraits,
+                secondaryComparatorFactories, keyFields, opHelperFactory);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, secondaryRTreeSearchOp, NC1_ID);
+
+        PrinterOperatorDescriptor printer = new PrinterOperatorDescriptor(spec);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC1_ID);
+
+        spec.connect(new OneToOneConnectorDescriptor(spec), keyProviderOp, 0, secondaryRTreeSearchOp, 0);
+        spec.connect(new OneToOneConnectorDescriptor(spec), secondaryRTreeSearchOp, 0, printer, 0);
+
+        spec.addRoot(printer);
+        runTest(spec);
+    }
+
+    @AfterClass
+    public static void cleanup() throws Exception {
+        File primary = new File(primaryFileName);
+        primary.deleteOnExit();
+
+        File primaryBTree = new File(primaryBTreeFileName);
+        primaryBTree.deleteOnExit();
+
+        File secondary = new File(secondaryFileName);
+        secondary.deleteOnExit();
+    }
+}
\ No newline at end of file
diff --git a/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/spillable/ExternalAggregateTest.java b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/spillable/ExternalAggregateTest.java
index 694f183..b107282 100644
--- a/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/spillable/ExternalAggregateTest.java
+++ b/hyracks-examples/hyracks-integration-tests/src/test/java/edu/uci/ics/hyracks/tests/spillable/ExternalAggregateTest.java
@@ -26,23 +26,24 @@
 import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
 import edu.uci.ics.hyracks.api.io.FileReference;
 import edu.uci.ics.hyracks.api.job.JobSpecification;
-import edu.uci.ics.hyracks.dataflow.common.data.comparators.IntegerBinaryComparatorFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.comparators.UTF8StringBinaryComparatorFactory;
-import edu.uci.ics.hyracks.dataflow.common.data.hash.IntegerBinaryHashFunctionFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.hash.UTF8StringBinaryHashFunctionFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.FloatSerializerDeserializer;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.normalizers.UTF8StringNormalizedKeyComputerFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.parsers.FloatParserFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.parsers.IValueParserFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.parsers.IntegerParserFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.parsers.UTF8StringParserFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.partition.FieldHashPartitionComputerFactory;
-import edu.uci.ics.hyracks.dataflow.std.aggregators.CountAggregatorFactory;
-import edu.uci.ics.hyracks.dataflow.std.aggregators.IFieldValueResultingAggregatorFactory;
-import edu.uci.ics.hyracks.dataflow.std.aggregators.MinMaxAggregatorFactory;
-import edu.uci.ics.hyracks.dataflow.std.aggregators.MultiAggregatorFactory;
-import edu.uci.ics.hyracks.dataflow.std.aggregators.SumAggregatorFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.AvgAggregatorDescriptorFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.ConcatAggregatorDescriptorFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.CountAggregatorDescriptorFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.IAggregatorDescriptorFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.IntSumAggregatorDescriptorFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.MultiAggregatorDescriptorFactory;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.connectors.MToNHashPartitioningConnectorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.connectors.OneToOneConnectorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.file.ConstantFileSplitProvider;
@@ -50,74 +51,107 @@
 import edu.uci.ics.hyracks.dataflow.std.file.FileScanOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.file.FileSplit;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.dataflow.std.group.ExternalHashGroupOperatorDescriptor;
-import edu.uci.ics.hyracks.dataflow.std.group.HashGroupOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.file.ITupleParserFactory;
+import edu.uci.ics.hyracks.dataflow.std.file.PlainFileWriterOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.group.ExternalGroupOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.group.HashSpillableGroupingTableFactory;
 import edu.uci.ics.hyracks.dataflow.std.misc.PrinterOperatorDescriptor;
 import edu.uci.ics.hyracks.tests.integration.AbstractIntegrationTest;
 
 /**
- * Test cases for external hash group operator.
+ * @author jarodwen
  */
 public class ExternalAggregateTest extends AbstractIntegrationTest {
 
-    /**
-     * Test 01: aggregate (count) on single field, on a simple data set.
-     * 
-     * @throws Exception
-     */
+    final IFileSplitProvider splitProvider = new ConstantFileSplitProvider(new FileSplit[] { new FileSplit(NC2_ID,
+            new FileReference(new File("data/tpch0.001/lineitem.tbl"))) });
+
+    static final String outSplitsPrefix = System.getProperty("java.io.tmpdir");
+
+    static final String outSplits1 = "nc1:" + outSplitsPrefix + "/aggregation_";
+    static final String outSplits2 = "nc2:" + outSplitsPrefix + "/aggregation_";
+
+    static final boolean isOutputFile = true;
+
+    final RecordDescriptor desc = new RecordDescriptor(new ISerializerDeserializer[] {
+            UTF8StringSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
+            IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
+            IntegerSerializerDeserializer.INSTANCE, FloatSerializerDeserializer.INSTANCE,
+            FloatSerializerDeserializer.INSTANCE, FloatSerializerDeserializer.INSTANCE,
+            UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+            UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+            UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+            UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE });
+
+    final ITupleParserFactory tupleParserFactory = new DelimitedDataTupleParserFactory(new IValueParserFactory[] {
+            UTF8StringParserFactory.INSTANCE, IntegerParserFactory.INSTANCE, IntegerParserFactory.INSTANCE,
+            IntegerParserFactory.INSTANCE, IntegerParserFactory.INSTANCE, FloatParserFactory.INSTANCE,
+            FloatParserFactory.INSTANCE, FloatParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
+            UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
+            UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
+            UTF8StringParserFactory.INSTANCE, }, '|');
+
+    private static FileSplit[] parseFileSplits(String fileSplits) {
+        String[] splits = fileSplits.split(",");
+        FileSplit[] fSplits = new FileSplit[splits.length];
+        for (int i = 0; i < splits.length; ++i) {
+            String s = splits[i].trim();
+            int idx = s.indexOf(':');
+            if (idx < 0) {
+                throw new IllegalArgumentException("File split " + s + " not well formed");
+            }
+            fSplits[i] = new FileSplit(s.substring(0, idx), new FileReference(new File(s.substring(idx + 1))));
+        }
+        return fSplits;
+    }
+
+    private static AbstractSingleActivityOperatorDescriptor getPrinter(JobSpecification spec, boolean isFile,
+            String prefix) {
+        AbstractSingleActivityOperatorDescriptor printer;
+
+        if (!isOutputFile)
+            printer = new PrinterOperatorDescriptor(spec);
+        else
+            printer = new PlainFileWriterOperatorDescriptor(spec, new ConstantFileSplitProvider(
+                    parseFileSplits(outSplits1 + prefix + ".nc1, " + outSplits2 + prefix + ".nc2")), "\t");
+
+        return printer;
+    }
+
     @Test
-    public void externalAggregateTestSingleFieldSimpleData() throws Exception {
+    public void hashSingleKeyScalarGroupTest() throws Exception {
         JobSpecification spec = new JobSpecification();
 
-        IFileSplitProvider splitProvider = new ConstantFileSplitProvider(new FileSplit[] {
-                new FileSplit(NC2_ID, new FileReference(new File("data/wordcount.tsv"))),
-                new FileSplit(NC1_ID, new FileReference(new File("data/wordcount.tsv"))) });
+        FileScanOperatorDescriptor csvScanner = new FileScanOperatorDescriptor(spec, splitProvider, tupleParserFactory,
+                desc);
 
-        // Input format: a string field as the key
-        RecordDescriptor desc = new RecordDescriptor(
-                new ISerializerDeserializer[] { UTF8StringSerializerDeserializer.INSTANCE });
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, csvScanner, NC2_ID);
 
-        // Output format: a string field as the key, and an integer field as the
-        // count
         RecordDescriptor outputRec = new RecordDescriptor(new ISerializerDeserializer[] {
                 UTF8StringSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE });
 
-        // Data set format: word(string),count(int)
-        FileScanOperatorDescriptor csvScanner = new FileScanOperatorDescriptor(
-                spec,
-                splitProvider,
-                new DelimitedDataTupleParserFactory(new IValueParserFactory[] { UTF8StringParserFactory.INSTANCE }, ','),
-                desc);
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, csvScanner, NC2_ID, NC1_ID);
-
-        int[] keys = new int[] { 0 };
+        int[] keyFields = new int[] { 0 };
+        int frameLimits = 3;
         int tableSize = 8;
 
-        ExternalHashGroupOperatorDescriptor grouper = new ExternalHashGroupOperatorDescriptor(
-                spec, // Job conf
-                keys, // Group key
-                3, // Number of frames
-                false, // Whether to sort the output
-                // Hash partitioner
-                new FieldHashPartitionComputerFactory(keys,
-                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }),
-                // Key comparator
+        ExternalGroupOperatorDescriptor grouper = new ExternalGroupOperatorDescriptor(spec, keyFields, frameLimits,
                 new IBinaryComparatorFactory[] { UTF8StringBinaryComparatorFactory.INSTANCE },
-                // Aggregator factory
-                new MultiAggregatorFactory(new IFieldValueResultingAggregatorFactory[] { new CountAggregatorFactory() }),
-                outputRec, // Output format
-                tableSize // Size of the hashing table, which is used to control
-        // the partition when hashing
-        );
+                new UTF8StringNormalizedKeyComputerFactory(), new CountAggregatorDescriptorFactory(),
+                new IntSumAggregatorDescriptorFactory(keyFields.length), outputRec,
+                new HashSpillableGroupingTableFactory(new FieldHashPartitionComputerFactory(keyFields,
+                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }), tableSize),
+                true);
 
         PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC2_ID, NC1_ID);
 
         IConnectorDescriptor conn1 = new MToNHashPartitioningConnectorDescriptor(spec,
-                new FieldHashPartitionComputerFactory(keys,
+                new FieldHashPartitionComputerFactory(keyFields,
                         new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }));
         spec.connect(conn1, csvScanner, 0, grouper, 0);
 
-        PrinterOperatorDescriptor printer = new PrinterOperatorDescriptor(spec);
+        AbstractSingleActivityOperatorDescriptor printer = getPrinter(spec, isOutputFile,
+                "hashSingleKeyScalarGroupTest");
+
         PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC2_ID, NC1_ID);
 
         IConnectorDescriptor conn2 = new OneToOneConnectorDescriptor(spec);
@@ -127,186 +161,41 @@
         runTest(spec);
     }
 
-    /**
-     * Test 02: Control experiment using in-memory aggregator, on the same data
-     * set of {@link #externalAggregateTest01()}
-     * 
-     * @throws Exception
-     */
     @Test
-    public void externalAggregateTestSingleFieldSimpleDataInMemControl() throws Exception {
+    public void hashMultipleKeyScalarGroupTest() throws Exception {
         JobSpecification spec = new JobSpecification();
 
-        IFileSplitProvider splitProvider = new ConstantFileSplitProvider(new FileSplit[] {
-                new FileSplit(NC2_ID, new FileReference(new File("data/wordcount.tsv"))),
-                new FileSplit(NC1_ID, new FileReference(new File("data/wordcount.tsv"))) });
-
-        RecordDescriptor desc = new RecordDescriptor(
-                new ISerializerDeserializer[] { UTF8StringSerializerDeserializer.INSTANCE });
-
-        RecordDescriptor outputRec = new RecordDescriptor(new ISerializerDeserializer[] {
-                UTF8StringSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE });
-
-        FileScanOperatorDescriptor csvScanner = new FileScanOperatorDescriptor(
-                spec,
-                splitProvider,
-                new DelimitedDataTupleParserFactory(new IValueParserFactory[] { UTF8StringParserFactory.INSTANCE }, ','),
+        FileScanOperatorDescriptor csvScanner = new FileScanOperatorDescriptor(spec, splitProvider, tupleParserFactory,
                 desc);
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, csvScanner, NC2_ID, NC1_ID);
 
-        int[] keys = new int[] { 0 };
-        int tableSize = 8;
-
-        HashGroupOperatorDescriptor grouper = new HashGroupOperatorDescriptor(
-                spec,
-                keys,
-                new FieldHashPartitionComputerFactory(keys,
-                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }),
-                new IBinaryComparatorFactory[] { UTF8StringBinaryComparatorFactory.INSTANCE },
-                new MultiAggregatorFactory(new IFieldValueResultingAggregatorFactory[] { new CountAggregatorFactory() }),
-                outputRec, tableSize);
-
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC2_ID, NC1_ID);
-
-        IConnectorDescriptor conn1 = new MToNHashPartitioningConnectorDescriptor(spec,
-                new FieldHashPartitionComputerFactory(keys,
-                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }));
-        spec.connect(conn1, csvScanner, 0, grouper, 0);
-
-        PrinterOperatorDescriptor printer = new PrinterOperatorDescriptor(spec);
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC2_ID, NC1_ID);
-
-        IConnectorDescriptor conn2 = new OneToOneConnectorDescriptor(spec);
-        spec.connect(conn2, grouper, 0, printer, 0);
-
-        spec.addRoot(printer);
-        runTest(spec);
-    }
-
-    /**
-     * Test 03: aggregates on multiple fields
-     * 
-     * @throws Exception
-     */
-    @Test
-    public void externalAggregateTestMultiAggFields() throws Exception {
-        JobSpecification spec = new JobSpecification();
-
-        FileSplit[] ordersSplits = new FileSplit[] { new FileSplit(NC2_ID, new FileReference(new File(
-                "data/tpch0.001/lineitem.tbl"))) };
-        IFileSplitProvider ordersSplitsProvider = new ConstantFileSplitProvider(ordersSplits);
-        RecordDescriptor ordersDesc = new RecordDescriptor(new ISerializerDeserializer[] {
-                UTF8StringSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE, FloatSerializerDeserializer.INSTANCE,
-                FloatSerializerDeserializer.INSTANCE, FloatSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE });
-
-        FileScanOperatorDescriptor ordScanner = new FileScanOperatorDescriptor(spec, ordersSplitsProvider,
-                new DelimitedDataTupleParserFactory(new IValueParserFactory[] { UTF8StringParserFactory.INSTANCE,
-                        IntegerParserFactory.INSTANCE, IntegerParserFactory.INSTANCE, IntegerParserFactory.INSTANCE,
-                        IntegerParserFactory.INSTANCE, FloatParserFactory.INSTANCE, FloatParserFactory.INSTANCE,
-                        FloatParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, }, '|'), ordersDesc);
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, ordScanner, NC1_ID);
-
-        RecordDescriptor outputRec = new RecordDescriptor(new ISerializerDeserializer[] {
-                UTF8StringSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE, FloatSerializerDeserializer.INSTANCE });
-
-        int[] keys = new int[] { 0 };
-        int tableSize = 8;
-
-        ExternalHashGroupOperatorDescriptor grouper = new ExternalHashGroupOperatorDescriptor(spec, keys, 3, false,
-                new FieldHashPartitionComputerFactory(keys,
-                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }),
-                new IBinaryComparatorFactory[] { UTF8StringBinaryComparatorFactory.INSTANCE },
-                new MultiAggregatorFactory(new IFieldValueResultingAggregatorFactory[] { new CountAggregatorFactory(),
-                        new SumAggregatorFactory(4), new MinMaxAggregatorFactory(true, 5) }), outputRec, tableSize);
-
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC1_ID);
-
-        IConnectorDescriptor conn1 = new MToNHashPartitioningConnectorDescriptor(spec,
-                new FieldHashPartitionComputerFactory(keys,
-                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }));
-        spec.connect(conn1, ordScanner, 0, grouper, 0);
-
-        PrinterOperatorDescriptor printer = new PrinterOperatorDescriptor(spec);
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC1_ID);
-
-        IConnectorDescriptor conn2 = new OneToOneConnectorDescriptor(spec);
-        spec.connect(conn2, grouper, 0, printer, 0);
-
-        spec.addRoot(printer);
-        runTest(spec);
-    }
-
-    /**
-     * Test 05: aggregate on multiple key fields
-     * 
-     * @throws Exception
-     */
-    @Test
-    public void externalAggregateTestMultiKeys() throws Exception {
-        JobSpecification spec = new JobSpecification();
-
-        FileSplit[] ordersSplits = new FileSplit[] { new FileSplit(NC2_ID, new FileReference(new File(
-                "data/tpch0.001/lineitem.tbl"))) };
-        IFileSplitProvider ordersSplitsProvider = new ConstantFileSplitProvider(ordersSplits);
-        RecordDescriptor ordersDesc = new RecordDescriptor(new ISerializerDeserializer[] {
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE, FloatSerializerDeserializer.INSTANCE,
-                FloatSerializerDeserializer.INSTANCE, FloatSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE });
-
-        FileScanOperatorDescriptor ordScanner = new FileScanOperatorDescriptor(spec, ordersSplitsProvider,
-                new DelimitedDataTupleParserFactory(new IValueParserFactory[] { UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, IntegerParserFactory.INSTANCE, IntegerParserFactory.INSTANCE,
-                        IntegerParserFactory.INSTANCE, FloatParserFactory.INSTANCE, FloatParserFactory.INSTANCE,
-                        FloatParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, }, '|'), ordersDesc);
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, ordScanner, NC1_ID);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, csvScanner, NC2_ID);
 
         RecordDescriptor outputRec = new RecordDescriptor(new ISerializerDeserializer[] {
                 UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
-                FloatSerializerDeserializer.INSTANCE });
+                IntegerSerializerDeserializer.INSTANCE, });
 
-        // Group on two fields
-        int[] keys = new int[] { 0, 1 };
+        int[] keyFields = new int[] { 0, 9 };
+        int frameLimits = 3;
         int tableSize = 8;
 
-        ExternalHashGroupOperatorDescriptor grouper = new ExternalHashGroupOperatorDescriptor(spec, keys, 3, false,
-                new FieldHashPartitionComputerFactory(keys, new IBinaryHashFunctionFactory[] {
-                        UTF8StringBinaryHashFunctionFactory.INSTANCE, UTF8StringBinaryHashFunctionFactory.INSTANCE }),
+        ExternalGroupOperatorDescriptor grouper = new ExternalGroupOperatorDescriptor(spec, keyFields, frameLimits,
                 new IBinaryComparatorFactory[] { UTF8StringBinaryComparatorFactory.INSTANCE,
-                        UTF8StringBinaryComparatorFactory.INSTANCE }, new MultiAggregatorFactory(
-                        new IFieldValueResultingAggregatorFactory[] { new CountAggregatorFactory(),
-                                new SumAggregatorFactory(4), new MinMaxAggregatorFactory(true, 5) }), outputRec,
-                tableSize);
+                        UTF8StringBinaryComparatorFactory.INSTANCE }, new UTF8StringNormalizedKeyComputerFactory(),
+                new IntSumAggregatorDescriptorFactory(1), new IntSumAggregatorDescriptorFactory(keyFields.length),
+                outputRec, new HashSpillableGroupingTableFactory(new FieldHashPartitionComputerFactory(keyFields,
+                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE,
+                                UTF8StringBinaryHashFunctionFactory.INSTANCE }), tableSize), true);
 
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC1_ID);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC2_ID, NC1_ID);
 
         IConnectorDescriptor conn1 = new MToNHashPartitioningConnectorDescriptor(spec,
-                new FieldHashPartitionComputerFactory(keys, new IBinaryHashFunctionFactory[] {
-                        UTF8StringBinaryHashFunctionFactory.INSTANCE, UTF8StringBinaryHashFunctionFactory.INSTANCE }));
-        spec.connect(conn1, ordScanner, 0, grouper, 0);
+                new FieldHashPartitionComputerFactory(keyFields, new IBinaryHashFunctionFactory[] {
+                        UTF8StringBinaryHashFunctionFactory.INSTANCE, UTF8StringBinaryHashFunctionFactory.INSTANCE, }));
+        spec.connect(conn1, csvScanner, 0, grouper, 0);
 
-        PrinterOperatorDescriptor printer = new PrinterOperatorDescriptor(spec);
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC1_ID);
+        AbstractSingleActivityOperatorDescriptor printer = getPrinter(spec, isOutputFile,
+                "hashMultipleKeyScalarGroupTest");
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC2_ID, NC1_ID);
 
         IConnectorDescriptor conn2 = new OneToOneConnectorDescriptor(spec);
         spec.connect(conn2, grouper, 0, printer, 0);
@@ -315,66 +204,44 @@
         runTest(spec);
     }
 
-    /**
-     * Test 06: tests on non-string key field
-     * 
-     * @throws Exception
-     */
     @Test
-    public void externalAggregateTestNonStringKey() throws Exception {
+    public void hashMultipleKeyMultipleScalarGroupTest() throws Exception {
         JobSpecification spec = new JobSpecification();
 
-        FileSplit[] ordersSplits = new FileSplit[] { new FileSplit(NC2_ID, new FileReference(new File(
-                "data/tpch0.001/lineitem.tbl"))) };
-        IFileSplitProvider ordersSplitsProvider = new ConstantFileSplitProvider(ordersSplits);
-        RecordDescriptor ordersDesc = new RecordDescriptor(new ISerializerDeserializer[] {
-                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE, FloatSerializerDeserializer.INSTANCE,
-                FloatSerializerDeserializer.INSTANCE, FloatSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
-                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE });
+        FileScanOperatorDescriptor csvScanner = new FileScanOperatorDescriptor(spec, splitProvider, tupleParserFactory,
+                desc);
 
-        FileScanOperatorDescriptor ordScanner = new FileScanOperatorDescriptor(spec, ordersSplitsProvider,
-                new DelimitedDataTupleParserFactory(new IValueParserFactory[] { IntegerParserFactory.INSTANCE,
-                        IntegerParserFactory.INSTANCE, IntegerParserFactory.INSTANCE, IntegerParserFactory.INSTANCE,
-                        IntegerParserFactory.INSTANCE, FloatParserFactory.INSTANCE, FloatParserFactory.INSTANCE,
-                        FloatParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, UTF8StringParserFactory.INSTANCE,
-                        UTF8StringParserFactory.INSTANCE, }, '|'), ordersDesc);
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, ordScanner, NC1_ID);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, csvScanner, NC2_ID);
 
         RecordDescriptor outputRec = new RecordDescriptor(new ISerializerDeserializer[] {
-                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
-                FloatSerializerDeserializer.INSTANCE });
+                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE, });
 
-        // Group on two fields
-        int[] keys = new int[] { 0, 1 };
+        int[] keyFields = new int[] { 0, 9 };
+        int frameLimits = 3;
         int tableSize = 8;
 
-        ExternalHashGroupOperatorDescriptor grouper = new ExternalHashGroupOperatorDescriptor(spec, keys, 3000, true,
-                new FieldHashPartitionComputerFactory(keys, new IBinaryHashFunctionFactory[] {
-                        IntegerBinaryHashFunctionFactory.INSTANCE, IntegerBinaryHashFunctionFactory.INSTANCE }),
-                new IBinaryComparatorFactory[] { IntegerBinaryComparatorFactory.INSTANCE,
-                        IntegerBinaryComparatorFactory.INSTANCE }, new MultiAggregatorFactory(
-                        new IFieldValueResultingAggregatorFactory[] { new CountAggregatorFactory(),
-                                new SumAggregatorFactory(4), new MinMaxAggregatorFactory(true, 5) }), outputRec,
-                tableSize);
+        ExternalGroupOperatorDescriptor grouper = new ExternalGroupOperatorDescriptor(spec, keyFields, frameLimits,
+                new IBinaryComparatorFactory[] { UTF8StringBinaryComparatorFactory.INSTANCE,
+                        UTF8StringBinaryComparatorFactory.INSTANCE }, new UTF8StringNormalizedKeyComputerFactory(),
+                new MultiAggregatorDescriptorFactory(new IAggregatorDescriptorFactory[] {
+                        new IntSumAggregatorDescriptorFactory(1, 2), new IntSumAggregatorDescriptorFactory(2, 3) }),
+                new MultiAggregatorDescriptorFactory(new IAggregatorDescriptorFactory[] {
+                        new IntSumAggregatorDescriptorFactory(2, 2), new IntSumAggregatorDescriptorFactory(3, 3) }),
+                outputRec, new HashSpillableGroupingTableFactory(new FieldHashPartitionComputerFactory(keyFields,
+                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE,
+                                UTF8StringBinaryHashFunctionFactory.INSTANCE }), tableSize), true);
 
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC1_ID);
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC2_ID, NC1_ID);
 
         IConnectorDescriptor conn1 = new MToNHashPartitioningConnectorDescriptor(spec,
-                new FieldHashPartitionComputerFactory(keys, new IBinaryHashFunctionFactory[] {
-                        IntegerBinaryHashFunctionFactory.INSTANCE, IntegerBinaryHashFunctionFactory.INSTANCE }));
-        spec.connect(conn1, ordScanner, 0, grouper, 0);
+                new FieldHashPartitionComputerFactory(keyFields, new IBinaryHashFunctionFactory[] {
+                        UTF8StringBinaryHashFunctionFactory.INSTANCE, UTF8StringBinaryHashFunctionFactory.INSTANCE, }));
+        spec.connect(conn1, csvScanner, 0, grouper, 0);
 
-        PrinterOperatorDescriptor printer = new PrinterOperatorDescriptor(spec);
-        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC1_ID);
+        AbstractSingleActivityOperatorDescriptor printer = getPrinter(spec, isOutputFile,
+                "hashMultipleKeyMultipleScalarGroupTest");
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC2_ID, NC1_ID);
 
         IConnectorDescriptor conn2 = new OneToOneConnectorDescriptor(spec);
         spec.connect(conn2, grouper, 0, printer, 0);
@@ -382,4 +249,138 @@
         spec.addRoot(printer);
         runTest(spec);
     }
-}
\ No newline at end of file
+
+    @Test
+    public void hashMultipleKeyNonScalarGroupTest() throws Exception {
+        JobSpecification spec = new JobSpecification();
+
+        FileScanOperatorDescriptor csvScanner = new FileScanOperatorDescriptor(spec, splitProvider, tupleParserFactory,
+                desc);
+
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, csvScanner, NC2_ID);
+
+        RecordDescriptor outputRec = new RecordDescriptor(new ISerializerDeserializer[] {
+                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE });
+
+        int[] keyFields = new int[] { 0 };
+        int frameLimits = 3;
+        int tableSize = 8;
+
+        ExternalGroupOperatorDescriptor grouper = new ExternalGroupOperatorDescriptor(spec, keyFields, frameLimits,
+                new IBinaryComparatorFactory[] { UTF8StringBinaryComparatorFactory.INSTANCE },
+                new UTF8StringNormalizedKeyComputerFactory(), new ConcatAggregatorDescriptorFactory(9),
+                new ConcatAggregatorDescriptorFactory(keyFields.length), outputRec,
+                new HashSpillableGroupingTableFactory(new FieldHashPartitionComputerFactory(keyFields,
+                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }), tableSize),
+                true);
+
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC2_ID, NC1_ID);
+
+        IConnectorDescriptor conn1 = new MToNHashPartitioningConnectorDescriptor(spec,
+                new FieldHashPartitionComputerFactory(keyFields,
+                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }));
+        spec.connect(conn1, csvScanner, 0, grouper, 0);
+
+        AbstractSingleActivityOperatorDescriptor printer = getPrinter(spec, isOutputFile,
+                "hashMultipleKeyNonScalarGroupTest");
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC2_ID, NC1_ID);
+
+        IConnectorDescriptor conn2 = new OneToOneConnectorDescriptor(spec);
+        spec.connect(conn2, grouper, 0, printer, 0);
+
+        spec.addRoot(printer);
+        runTest(spec);
+    }
+
+    @Test
+    public void hashMultipleKeyMultipleFieldsGroupTest() throws Exception {
+        JobSpecification spec = new JobSpecification();
+
+        FileScanOperatorDescriptor csvScanner = new FileScanOperatorDescriptor(spec, splitProvider, tupleParserFactory,
+                desc);
+
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, csvScanner, NC2_ID);
+
+        RecordDescriptor outputRec = new RecordDescriptor(new ISerializerDeserializer[] {
+                UTF8StringSerializerDeserializer.INSTANCE, UTF8StringSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
+                UTF8StringSerializerDeserializer.INSTANCE });
+
+        int[] keyFields = new int[] { 0, 9 };
+        int frameLimits = 3;
+        int tableSize = 8;
+
+        ExternalGroupOperatorDescriptor grouper = new ExternalGroupOperatorDescriptor(spec, keyFields, frameLimits,
+                new IBinaryComparatorFactory[] { UTF8StringBinaryComparatorFactory.INSTANCE,
+                        UTF8StringBinaryComparatorFactory.INSTANCE }, new UTF8StringNormalizedKeyComputerFactory(),
+                new MultiAggregatorDescriptorFactory(new IAggregatorDescriptorFactory[] {
+                        new IntSumAggregatorDescriptorFactory(1, 2), new IntSumAggregatorDescriptorFactory(2, 3),
+                        new ConcatAggregatorDescriptorFactory(9, 4) }), new MultiAggregatorDescriptorFactory(
+                        new IAggregatorDescriptorFactory[] { new IntSumAggregatorDescriptorFactory(2, 2),
+                                new IntSumAggregatorDescriptorFactory(3, 3),
+                                new ConcatAggregatorDescriptorFactory(4, 4) }), outputRec,
+                new HashSpillableGroupingTableFactory(new FieldHashPartitionComputerFactory(keyFields,
+                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE,
+                                UTF8StringBinaryHashFunctionFactory.INSTANCE }), tableSize), true);
+
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC2_ID, NC1_ID);
+
+        IConnectorDescriptor conn1 = new MToNHashPartitioningConnectorDescriptor(spec,
+                new FieldHashPartitionComputerFactory(keyFields, new IBinaryHashFunctionFactory[] {
+                        UTF8StringBinaryHashFunctionFactory.INSTANCE, UTF8StringBinaryHashFunctionFactory.INSTANCE, }));
+        spec.connect(conn1, csvScanner, 0, grouper, 0);
+
+        AbstractSingleActivityOperatorDescriptor printer = getPrinter(spec, isOutputFile,
+                "hashMultipleKeyMultipleFieldsGroupTest");
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC2_ID, NC1_ID);
+
+        IConnectorDescriptor conn2 = new OneToOneConnectorDescriptor(spec);
+        spec.connect(conn2, grouper, 0, printer, 0);
+
+        spec.addRoot(printer);
+        runTest(spec);
+    }
+
+    @Test
+    public void hashSingleKeyScalarAvgGroupTest() throws Exception {
+        JobSpecification spec = new JobSpecification();
+
+        FileScanOperatorDescriptor csvScanner = new FileScanOperatorDescriptor(spec, splitProvider, tupleParserFactory,
+                desc);
+
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, csvScanner, NC2_ID);
+
+        RecordDescriptor outputRec = new RecordDescriptor(new ISerializerDeserializer[] {
+                UTF8StringSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE });
+
+        int[] keyFields = new int[] { 0 };
+        int frameLimits = 3;
+        int tableSize = 8;
+
+        ExternalGroupOperatorDescriptor grouper = new ExternalGroupOperatorDescriptor(spec, keyFields, frameLimits,
+                new IBinaryComparatorFactory[] { UTF8StringBinaryComparatorFactory.INSTANCE },
+                new UTF8StringNormalizedKeyComputerFactory(), new AvgAggregatorDescriptorFactory(1),
+                new AvgAggregatorDescriptorFactory(keyFields.length), outputRec, new HashSpillableGroupingTableFactory(
+                        new FieldHashPartitionComputerFactory(keyFields,
+                                new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }),
+                        tableSize), true);
+
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, grouper, NC2_ID, NC1_ID);
+
+        IConnectorDescriptor conn1 = new MToNHashPartitioningConnectorDescriptor(spec,
+                new FieldHashPartitionComputerFactory(keyFields,
+                        new IBinaryHashFunctionFactory[] { UTF8StringBinaryHashFunctionFactory.INSTANCE }));
+        spec.connect(conn1, csvScanner, 0, grouper, 0);
+
+        AbstractSingleActivityOperatorDescriptor printer = getPrinter(spec, isOutputFile,
+                "hashSingleKeyScalarGroupTest");
+
+        PartitionConstraintHelper.addAbsoluteLocationConstraint(spec, printer, NC2_ID, NC1_ID);
+
+        IConnectorDescriptor conn2 = new OneToOneConnectorDescriptor(spec);
+        spec.connect(conn2, grouper, 0, printer, 0);
+
+        spec.addRoot(printer);
+        runTest(spec);
+    }
+}
diff --git a/hyracks-examples/text-example/textclient/.settings/org.eclipse.jdt.core.prefs b/hyracks-examples/text-example/textclient/.settings/org.eclipse.jdt.core.prefs
index 8599738..dfac000 100644
--- a/hyracks-examples/text-example/textclient/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-examples/text-example/textclient/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Tue Sep 28 14:37:42 PDT 2010
+#Fri May 20 19:34:05 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-examples/text-example/textclient/src/main/java/edu/uci/ics/hyracks/examples/text/client/ExternalGroupClient.java b/hyracks-examples/text-example/textclient/src/main/java/edu/uci/ics/hyracks/examples/text/client/ExternalGroupClient.java
index 8d22bca..b02b0ee 100644
--- a/hyracks-examples/text-example/textclient/src/main/java/edu/uci/ics/hyracks/examples/text/client/ExternalGroupClient.java
+++ b/hyracks-examples/text-example/textclient/src/main/java/edu/uci/ics/hyracks/examples/text/client/ExternalGroupClient.java
@@ -36,13 +36,18 @@
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.FloatSerializerDeserializer;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.normalizers.IntegerNormalizedKeyComputerFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.parsers.FloatParserFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.parsers.IValueParserFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.parsers.IntegerParserFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.parsers.UTF8StringParserFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.partition.FieldHashPartitionComputerFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.CountAggregatorDescriptorFactory;
 import edu.uci.ics.hyracks.dataflow.std.aggregators.CountAggregatorFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.IAggregatorDescriptorFactory;
 import edu.uci.ics.hyracks.dataflow.std.aggregators.IFieldValueResultingAggregatorFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.IntSumAggregatorDescriptorFactory;
+import edu.uci.ics.hyracks.dataflow.std.aggregators.MultiAggregatorDescriptorFactory;
 import edu.uci.ics.hyracks.dataflow.std.aggregators.MultiAggregatorFactory;
 import edu.uci.ics.hyracks.dataflow.std.base.AbstractOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor;
@@ -55,8 +60,9 @@
 import edu.uci.ics.hyracks.dataflow.std.file.FrameFileWriterOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
 import edu.uci.ics.hyracks.dataflow.std.file.PlainFileWriterOperatorDescriptor;
-import edu.uci.ics.hyracks.dataflow.std.group.ExternalHashGroupOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.group.ExternalGroupOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.group.HashGroupOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.group.HashSpillableGroupingTableFactory;
 import edu.uci.ics.hyracks.dataflow.std.group.PreclusteredGroupOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.sort.ExternalSortOperatorDescriptor;
 
@@ -112,7 +118,7 @@
         for (int i = 0; i < 3; i++) {
             long start = System.currentTimeMillis();
             job = createJob(parseFileSplits(options.inFileSplits), parseFileSplits(options.outFileSplits, i % 2),
-                    options.htSize, options.sbSize, options.framesLimit, options.sortOutput, i % 2, options.outPlain);
+                    options.htSize, options.sbSize, options.framesLimit, options.sortOutput, i % 3, options.outPlain);
 
             System.out.print(i + "\t" + (System.currentTimeMillis() - start));
             start = System.currentTimeMillis();
@@ -195,14 +201,22 @@
 
         switch (alg) {
             case 0: // External hash group
-                grouper = new ExternalHashGroupOperatorDescriptor(spec, keys, framesLimit, false,
-                        new FieldHashPartitionComputerFactory(keys, new IBinaryHashFunctionFactory[] {
-                        // IntegerBinaryHashFunctionFactory.INSTANCE,
-                                IntegerBinaryHashFunctionFactory.INSTANCE }), new IBinaryComparatorFactory[] {
+                grouper = new ExternalGroupOperatorDescriptor(
+                        spec,
+                        keys,
+                        framesLimit,
+                        new IBinaryComparatorFactory[] {
                         // IntegerBinaryComparatorFactory.INSTANCE,
-                        IntegerBinaryComparatorFactory.INSTANCE }, new MultiAggregatorFactory(
-                                new IFieldValueResultingAggregatorFactory[] { new CountAggregatorFactory() }), outDesc,
-                        htSize);
+                        IntegerBinaryComparatorFactory.INSTANCE },
+                        new IntegerNormalizedKeyComputerFactory(),
+                        new MultiAggregatorDescriptorFactory(
+                                new IAggregatorDescriptorFactory[] { new CountAggregatorDescriptorFactory() }),
+                        new MultiAggregatorDescriptorFactory(
+                                new IAggregatorDescriptorFactory[] { new IntSumAggregatorDescriptorFactory(keys.length) }),
+                        outDesc, new HashSpillableGroupingTableFactory(new FieldHashPartitionComputerFactory(keys,
+                                new IBinaryHashFunctionFactory[] {
+                                // IntegerBinaryHashFunctionFactory.INSTANCE,
+                                IntegerBinaryHashFunctionFactory.INSTANCE }), htSize), false);
 
                 createPartitionConstraint(spec, grouper, outSplits);
 
@@ -258,23 +272,31 @@
                 spec.connect(scanConn, fileScanner, 0, grouper, 0);
                 break;
             default:
-                grouper = new ExternalHashGroupOperatorDescriptor(spec, keys, framesLimit, false,
-                        new FieldHashPartitionComputerFactory(keys, new IBinaryHashFunctionFactory[] {
-                        // IntegerBinaryHashFunctionFactory.INSTANCE,
-                                IntegerBinaryHashFunctionFactory.INSTANCE }), new IBinaryComparatorFactory[] {
+                grouper = new ExternalGroupOperatorDescriptor(
+                        spec,
+                        keys,
+                        framesLimit,
+                        new IBinaryComparatorFactory[] {
                         // IntegerBinaryComparatorFactory.INSTANCE,
-                        IntegerBinaryComparatorFactory.INSTANCE }, new MultiAggregatorFactory(
-                                new IFieldValueResultingAggregatorFactory[] { new CountAggregatorFactory() }), outDesc,
-                        htSize);
+                        IntegerBinaryComparatorFactory.INSTANCE },
+                        new IntegerNormalizedKeyComputerFactory(),
+                        new MultiAggregatorDescriptorFactory(
+                                new IAggregatorDescriptorFactory[] { new CountAggregatorDescriptorFactory() }),
+                        new MultiAggregatorDescriptorFactory(
+                                new IAggregatorDescriptorFactory[] { new IntSumAggregatorDescriptorFactory(keys.length) }),
+                        outDesc, new HashSpillableGroupingTableFactory(new FieldHashPartitionComputerFactory(keys,
+                                new IBinaryHashFunctionFactory[] {
+                                // IntegerBinaryHashFunctionFactory.INSTANCE,
+                                IntegerBinaryHashFunctionFactory.INSTANCE }), htSize), false);
 
                 createPartitionConstraint(spec, grouper, outSplits);
 
                 // Connect scanner with the grouper
-                IConnectorDescriptor scanGroupConnDef = new MToNHashPartitioningConnectorDescriptor(spec,
+                IConnectorDescriptor defaultGroupConn = new MToNHashPartitioningConnectorDescriptor(spec,
                         new FieldHashPartitionComputerFactory(keys, new IBinaryHashFunctionFactory[] {
                         // IntegerBinaryHashFunctionFactory.INSTANCE,
                                 IntegerBinaryHashFunctionFactory.INSTANCE }));
-                spec.connect(scanGroupConnDef, fileScanner, 0, grouper, 0);
+                spec.connect(defaultGroupConn, fileScanner, 0, grouper, 0);
         }
 
         IFileSplitProvider outSplitProvider = new ConstantFileSplitProvider(outSplits);
diff --git a/hyracks-examples/text-example/texthelper/.settings/org.eclipse.jdt.core.prefs b/hyracks-examples/text-example/texthelper/.settings/org.eclipse.jdt.core.prefs
index 8599738..dfac000 100644
--- a/hyracks-examples/text-example/texthelper/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-examples/text-example/texthelper/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Tue Sep 28 14:37:42 PDT 2010
+#Fri May 20 19:34:05 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-examples/tpch-example/tpchapp/.classpath b/hyracks-examples/tpch-example/tpchapp/.classpath
index 3f62785..d0bec0f 100644
--- a/hyracks-examples/tpch-example/tpchapp/.classpath
+++ b/hyracks-examples/tpch-example/tpchapp/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.4"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.5"/>
 	<classpathentry kind="con" path="org.maven.ide.eclipse.MAVEN2_CLASSPATH_CONTAINER"/>
 	<classpathentry kind="output" path="target/classes"/>
 </classpath>
diff --git a/hyracks-examples/tpch-example/tpchapp/.settings/org.eclipse.jdt.core.prefs b/hyracks-examples/tpch-example/tpchapp/.settings/org.eclipse.jdt.core.prefs
index 14ece6a..b61b886 100644
--- a/hyracks-examples/tpch-example/tpchapp/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-examples/tpch-example/tpchapp/.settings/org.eclipse.jdt.core.prefs
@@ -1,6 +1,6 @@
-#Sun Aug 29 19:38:13 PDT 2010
+#Thu Aug 04 11:50:35 PDT 2011
 eclipse.preferences.version=1
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.4
-org.eclipse.jdt.core.compiler.compliance=1.4
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.5
+org.eclipse.jdt.core.compiler.compliance=1.5
 org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
-org.eclipse.jdt.core.compiler.source=1.4
+org.eclipse.jdt.core.compiler.source=1.5
diff --git a/hyracks-examples/tpch-example/tpchclient/.settings/org.eclipse.jdt.core.prefs b/hyracks-examples/tpch-example/tpchclient/.settings/org.eclipse.jdt.core.prefs
index 2f0f2e3..375e12e 100644
--- a/hyracks-examples/tpch-example/tpchclient/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-examples/tpch-example/tpchclient/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Wed Aug 11 19:09:15 PDT 2010
+#Fri May 20 19:34:07 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-hadoop-compat/.settings/org.eclipse.jdt.core.prefs b/hyracks-hadoop-compat/.settings/org.eclipse.jdt.core.prefs
index 0b1e408..dfac000 100644
--- a/hyracks-hadoop-compat/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-hadoop-compat/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Tue Nov 02 17:09:03 PDT 2010
+#Fri May 20 19:34:05 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-server/.classpath b/hyracks-server/.classpath
index 3f62785..d0bec0f 100644
--- a/hyracks-server/.classpath
+++ b/hyracks-server/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.4"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.5"/>
 	<classpathentry kind="con" path="org.maven.ide.eclipse.MAVEN2_CLASSPATH_CONTAINER"/>
 	<classpathentry kind="output" path="target/classes"/>
 </classpath>
diff --git a/hyracks-server/.settings/org.eclipse.jdt.core.prefs b/hyracks-server/.settings/org.eclipse.jdt.core.prefs
index 14ece6a..b61b886 100644
--- a/hyracks-server/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-server/.settings/org.eclipse.jdt.core.prefs
@@ -1,6 +1,6 @@
-#Sun Aug 29 19:38:13 PDT 2010
+#Thu Aug 04 11:50:35 PDT 2011
 eclipse.preferences.version=1
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.4
-org.eclipse.jdt.core.compiler.compliance=1.4
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.5
+org.eclipse.jdt.core.compiler.compliance=1.5
 org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
-org.eclipse.jdt.core.compiler.source=1.4
+org.eclipse.jdt.core.compiler.source=1.5
diff --git a/hyracks-storage-am-btree/.settings/org.eclipse.jdt.core.prefs b/hyracks-storage-am-btree/.settings/org.eclipse.jdt.core.prefs
index 0eb07fa..451c926 100644
--- a/hyracks-storage-am-btree/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-storage-am-btree/.settings/org.eclipse.jdt.core.prefs
@@ -1,6 +1,264 @@
-#Mon Aug 30 11:42:12 PDT 2010
+#Fri May 20 19:34:05 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
 org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
 org.eclipse.jdt.core.compiler.source=1.6
+org.eclipse.jdt.core.formatter.align_type_members_on_columns=false
+org.eclipse.jdt.core.formatter.alignment_for_arguments_in_allocation_expression=16
+org.eclipse.jdt.core.formatter.alignment_for_arguments_in_enum_constant=48
+org.eclipse.jdt.core.formatter.alignment_for_arguments_in_explicit_constructor_call=16
+org.eclipse.jdt.core.formatter.alignment_for_arguments_in_method_invocation=16
+org.eclipse.jdt.core.formatter.alignment_for_arguments_in_qualified_allocation_expression=16
+org.eclipse.jdt.core.formatter.alignment_for_assignment=0
+org.eclipse.jdt.core.formatter.alignment_for_binary_expression=16
+org.eclipse.jdt.core.formatter.alignment_for_compact_if=16
+org.eclipse.jdt.core.formatter.alignment_for_conditional_expression=80
+org.eclipse.jdt.core.formatter.alignment_for_enum_constants=48
+org.eclipse.jdt.core.formatter.alignment_for_expressions_in_array_initializer=16
+org.eclipse.jdt.core.formatter.alignment_for_multiple_fields=16
+org.eclipse.jdt.core.formatter.alignment_for_parameters_in_constructor_declaration=16
+org.eclipse.jdt.core.formatter.alignment_for_parameters_in_method_declaration=16
+org.eclipse.jdt.core.formatter.alignment_for_selector_in_method_invocation=16
+org.eclipse.jdt.core.formatter.alignment_for_superclass_in_type_declaration=16
+org.eclipse.jdt.core.formatter.alignment_for_superinterfaces_in_enum_declaration=16
+org.eclipse.jdt.core.formatter.alignment_for_superinterfaces_in_type_declaration=16
+org.eclipse.jdt.core.formatter.alignment_for_throws_clause_in_constructor_declaration=16
+org.eclipse.jdt.core.formatter.alignment_for_throws_clause_in_method_declaration=16
+org.eclipse.jdt.core.formatter.blank_lines_after_imports=1
+org.eclipse.jdt.core.formatter.blank_lines_after_package=1
+org.eclipse.jdt.core.formatter.blank_lines_before_field=0
+org.eclipse.jdt.core.formatter.blank_lines_before_first_class_body_declaration=0
+org.eclipse.jdt.core.formatter.blank_lines_before_imports=1
+org.eclipse.jdt.core.formatter.blank_lines_before_member_type=1
+org.eclipse.jdt.core.formatter.blank_lines_before_method=1
+org.eclipse.jdt.core.formatter.blank_lines_before_new_chunk=1
+org.eclipse.jdt.core.formatter.blank_lines_before_package=0
+org.eclipse.jdt.core.formatter.blank_lines_between_import_groups=1
+org.eclipse.jdt.core.formatter.blank_lines_between_type_declarations=1
+org.eclipse.jdt.core.formatter.brace_position_for_annotation_type_declaration=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_anonymous_type_declaration=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_array_initializer=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_block=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_block_in_case=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_constructor_declaration=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_enum_constant=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_enum_declaration=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_method_declaration=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_switch=end_of_line
+org.eclipse.jdt.core.formatter.brace_position_for_type_declaration=end_of_line
+org.eclipse.jdt.core.formatter.comment.clear_blank_lines_in_block_comment=false
+org.eclipse.jdt.core.formatter.comment.clear_blank_lines_in_javadoc_comment=false
+org.eclipse.jdt.core.formatter.comment.format_block_comments=true
+org.eclipse.jdt.core.formatter.comment.format_header=false
+org.eclipse.jdt.core.formatter.comment.format_html=true
+org.eclipse.jdt.core.formatter.comment.format_javadoc_comments=true
+org.eclipse.jdt.core.formatter.comment.format_line_comments=true
+org.eclipse.jdt.core.formatter.comment.format_source_code=true
+org.eclipse.jdt.core.formatter.comment.indent_parameter_description=true
+org.eclipse.jdt.core.formatter.comment.indent_root_tags=true
+org.eclipse.jdt.core.formatter.comment.insert_new_line_before_root_tags=insert
+org.eclipse.jdt.core.formatter.comment.insert_new_line_for_parameter=insert
+org.eclipse.jdt.core.formatter.comment.line_length=80
+org.eclipse.jdt.core.formatter.compact_else_if=true
+org.eclipse.jdt.core.formatter.continuation_indentation=2
+org.eclipse.jdt.core.formatter.continuation_indentation_for_array_initializer=2
+org.eclipse.jdt.core.formatter.format_guardian_clause_on_one_line=false
+org.eclipse.jdt.core.formatter.indent_body_declarations_compare_to_annotation_declaration_header=true
+org.eclipse.jdt.core.formatter.indent_body_declarations_compare_to_enum_constant_header=true
+org.eclipse.jdt.core.formatter.indent_body_declarations_compare_to_enum_declaration_header=true
+org.eclipse.jdt.core.formatter.indent_body_declarations_compare_to_type_header=true
+org.eclipse.jdt.core.formatter.indent_breaks_compare_to_cases=true
+org.eclipse.jdt.core.formatter.indent_empty_lines=false
+org.eclipse.jdt.core.formatter.indent_statements_compare_to_block=true
+org.eclipse.jdt.core.formatter.indent_statements_compare_to_body=true
+org.eclipse.jdt.core.formatter.indent_switchstatements_compare_to_cases=true
+org.eclipse.jdt.core.formatter.indent_switchstatements_compare_to_switch=true
+org.eclipse.jdt.core.formatter.indentation.size=4
+org.eclipse.jdt.core.formatter.insert_new_line_after_annotation_on_local_variable=insert
+org.eclipse.jdt.core.formatter.insert_new_line_after_annotation_on_member=insert
+org.eclipse.jdt.core.formatter.insert_new_line_after_annotation_on_parameter=do not insert
+org.eclipse.jdt.core.formatter.insert_new_line_after_opening_brace_in_array_initializer=do not insert
+org.eclipse.jdt.core.formatter.insert_new_line_at_end_of_file_if_missing=do not insert
+org.eclipse.jdt.core.formatter.insert_new_line_before_catch_in_try_statement=do not insert
+org.eclipse.jdt.core.formatter.insert_new_line_before_closing_brace_in_array_initializer=do not insert
+org.eclipse.jdt.core.formatter.insert_new_line_before_else_in_if_statement=do not insert
+org.eclipse.jdt.core.formatter.insert_new_line_before_finally_in_try_statement=do not insert
+org.eclipse.jdt.core.formatter.insert_new_line_before_while_in_do_statement=do not insert
+org.eclipse.jdt.core.formatter.insert_new_line_in_empty_annotation_declaration=insert
+org.eclipse.jdt.core.formatter.insert_new_line_in_empty_anonymous_type_declaration=insert
+org.eclipse.jdt.core.formatter.insert_new_line_in_empty_block=insert
+org.eclipse.jdt.core.formatter.insert_new_line_in_empty_enum_constant=insert
+org.eclipse.jdt.core.formatter.insert_new_line_in_empty_enum_declaration=insert
+org.eclipse.jdt.core.formatter.insert_new_line_in_empty_method_body=insert
+org.eclipse.jdt.core.formatter.insert_new_line_in_empty_type_declaration=insert
+org.eclipse.jdt.core.formatter.insert_space_after_and_in_type_parameter=insert
+org.eclipse.jdt.core.formatter.insert_space_after_assignment_operator=insert
+org.eclipse.jdt.core.formatter.insert_space_after_at_in_annotation=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_at_in_annotation_type_declaration=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_binary_operator=insert
+org.eclipse.jdt.core.formatter.insert_space_after_closing_angle_bracket_in_type_arguments=insert
+org.eclipse.jdt.core.formatter.insert_space_after_closing_angle_bracket_in_type_parameters=insert
+org.eclipse.jdt.core.formatter.insert_space_after_closing_brace_in_block=insert
+org.eclipse.jdt.core.formatter.insert_space_after_closing_paren_in_cast=insert
+org.eclipse.jdt.core.formatter.insert_space_after_colon_in_assert=insert
+org.eclipse.jdt.core.formatter.insert_space_after_colon_in_case=insert
+org.eclipse.jdt.core.formatter.insert_space_after_colon_in_conditional=insert
+org.eclipse.jdt.core.formatter.insert_space_after_colon_in_for=insert
+org.eclipse.jdt.core.formatter.insert_space_after_colon_in_labeled_statement=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_allocation_expression=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_annotation=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_array_initializer=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_constructor_declaration_parameters=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_constructor_declaration_throws=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_enum_constant_arguments=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_enum_declarations=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_explicitconstructorcall_arguments=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_for_increments=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_for_inits=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_method_declaration_parameters=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_method_declaration_throws=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_method_invocation_arguments=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_multiple_field_declarations=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_multiple_local_declarations=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_parameterized_type_reference=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_superinterfaces=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_type_arguments=insert
+org.eclipse.jdt.core.formatter.insert_space_after_comma_in_type_parameters=insert
+org.eclipse.jdt.core.formatter.insert_space_after_ellipsis=insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_angle_bracket_in_parameterized_type_reference=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_angle_bracket_in_type_arguments=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_angle_bracket_in_type_parameters=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_brace_in_array_initializer=insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_bracket_in_array_allocation_expression=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_bracket_in_array_reference=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_annotation=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_cast=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_constructor_declaration=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_enum_constant=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_for=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_if=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_parenthesized_expression=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_switch=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_synchronized=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_opening_paren_in_while=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_postfix_operator=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_prefix_operator=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_question_in_conditional=insert
+org.eclipse.jdt.core.formatter.insert_space_after_question_in_wildcard=do not insert
+org.eclipse.jdt.core.formatter.insert_space_after_semicolon_in_for=insert
+org.eclipse.jdt.core.formatter.insert_space_after_unary_operator=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_and_in_type_parameter=insert
+org.eclipse.jdt.core.formatter.insert_space_before_assignment_operator=insert
+org.eclipse.jdt.core.formatter.insert_space_before_at_in_annotation_type_declaration=insert
+org.eclipse.jdt.core.formatter.insert_space_before_binary_operator=insert
+org.eclipse.jdt.core.formatter.insert_space_before_closing_angle_bracket_in_parameterized_type_reference=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_before_closing_angle_bracket_in_type_parameters=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_closing_brace_in_array_initializer=insert
+org.eclipse.jdt.core.formatter.insert_space_before_closing_bracket_in_array_allocation_expression=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_closing_bracket_in_array_reference=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_closing_paren_in_annotation=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_closing_paren_in_cast=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_before_closing_paren_in_enum_constant=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_before_closing_paren_in_method_invocation=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_closing_paren_in_parenthesized_expression=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_before_closing_paren_in_synchronized=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_closing_paren_in_while=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_colon_in_assert=insert
+org.eclipse.jdt.core.formatter.insert_space_before_colon_in_case=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_colon_in_conditional=insert
+org.eclipse.jdt.core.formatter.insert_space_before_colon_in_default=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_colon_in_for=insert
+org.eclipse.jdt.core.formatter.insert_space_before_colon_in_labeled_statement=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_allocation_expression=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_annotation=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_constructor_declaration_throws=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_enum_constant_arguments=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_enum_declarations=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_explicitconstructorcall_arguments=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_for_increments=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_for_inits=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_method_declaration_parameters=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_method_invocation_arguments=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_multiple_field_declarations=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_multiple_local_declarations=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_parameterized_type_reference=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_superinterfaces=do not insert
+org.eclipse.jdt.core.formatter.insert_space_before_comma_in_type_arguments=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_before_opening_angle_bracket_in_parameterized_type_reference=do not insert
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+org.eclipse.jdt.core.formatter.insert_space_before_opening_brace_in_annotation_type_declaration=insert
+org.eclipse.jdt.core.formatter.insert_space_before_opening_brace_in_anonymous_type_declaration=insert
+org.eclipse.jdt.core.formatter.insert_space_before_opening_brace_in_array_initializer=insert
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+org.eclipse.jdt.core.formatter.insert_space_before_opening_paren_in_switch=insert
+org.eclipse.jdt.core.formatter.insert_space_before_opening_paren_in_synchronized=insert
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+org.eclipse.jdt.core.formatter.insert_space_between_empty_parens_in_method_declaration=do not insert
+org.eclipse.jdt.core.formatter.insert_space_between_empty_parens_in_method_invocation=do not insert
+org.eclipse.jdt.core.formatter.join_lines_in_comments=true
+org.eclipse.jdt.core.formatter.join_wrapped_lines=true
+org.eclipse.jdt.core.formatter.keep_else_statement_on_same_line=false
+org.eclipse.jdt.core.formatter.keep_empty_array_initializer_on_one_line=false
+org.eclipse.jdt.core.formatter.keep_imple_if_on_one_line=false
+org.eclipse.jdt.core.formatter.keep_then_statement_on_same_line=false
+org.eclipse.jdt.core.formatter.lineSplit=120
+org.eclipse.jdt.core.formatter.never_indent_block_comments_on_first_column=false
+org.eclipse.jdt.core.formatter.never_indent_line_comments_on_first_column=false
+org.eclipse.jdt.core.formatter.number_of_blank_lines_at_beginning_of_method_body=0
+org.eclipse.jdt.core.formatter.number_of_empty_lines_to_preserve=1
+org.eclipse.jdt.core.formatter.put_empty_statement_on_new_line=true
+org.eclipse.jdt.core.formatter.tabulation.char=space
+org.eclipse.jdt.core.formatter.tabulation.size=4
+org.eclipse.jdt.core.formatter.use_tabs_only_for_leading_indentations=false
+org.eclipse.jdt.core.formatter.wrap_before_binary_operator=true
diff --git a/hyracks-storage-am-btree/pom.xml b/hyracks-storage-am-btree/pom.xml
index c51ce70..0ef06c0 100644
--- a/hyracks-storage-am-btree/pom.xml
+++ b/hyracks-storage-am-btree/pom.xml
@@ -31,6 +31,13 @@
   		<type>jar</type>
   		<scope>compile</scope>
   	</dependency>  	
+        <dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-storage-am-common</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>  	
   	<dependency>
   		<groupId>edu.uci.ics.hyracks</groupId>
   		<artifactId>hyracks-dataflow-common</artifactId>
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeInteriorFrame.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeInteriorFrame.java
index 675bee3..25ab167 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeInteriorFrame.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeInteriorFrame.java
@@ -15,10 +15,15 @@
 
 package edu.uci.ics.hyracks.storage.am.btree.api;
 
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
-public interface IBTreeInteriorFrame extends IBTreeFrame {
+public interface IBTreeInteriorFrame extends ITreeIndexFrame {
+    public void insertSorted(ITupleReference tuple, MultiComparator cmp) throws HyracksDataException;
+    
     public int getChildPageId(RangePredicate pred, MultiComparator srcCmp);
 
     public int getLeftmostChildPageId(MultiComparator cmp);
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeInteriorFrameFactory.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeInteriorFrameFactory.java
deleted file mode 100644
index bddd636..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeInteriorFrameFactory.java
+++ /dev/null
@@ -1,22 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.btree.api;
-
-import java.io.Serializable;
-
-public interface IBTreeInteriorFrameFactory extends Serializable {
-    public IBTreeInteriorFrame getFrame();
-}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrame.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrame.java
index 9eb449c..53d892e 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrame.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrame.java
@@ -15,12 +15,17 @@
 
 package edu.uci.ics.hyracks.storage.am.btree.api;
 
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleMode;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleNoExactMatchPolicy;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
-public interface IBTreeLeafFrame extends IBTreeFrame {
+public interface IBTreeLeafFrame extends ITreeIndexFrame {
+    public void insertSorted(ITupleReference tuple, MultiComparator cmp) throws HyracksDataException;
+    
     public void setNextLeaf(int nextPage);
 
     public int getNextLeaf();
@@ -29,8 +34,8 @@
 
     public int getPrevLeaf();
 
-    public IBTreeTupleReference createTupleReference();
+    public ITreeIndexTupleReference createTupleReference();
 
-    public int findTupleIndex(ITupleReference searchKey, IBTreeTupleReference pageTuple, MultiComparator cmp,
+    public int findTupleIndex(ITupleReference searchKey, ITreeIndexTupleReference pageTuple, MultiComparator cmp,
             FindTupleMode ftm, FindTupleNoExactMatchPolicy ftp);
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleWriterFactory.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleWriterFactory.java
deleted file mode 100644
index 645c430..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleWriterFactory.java
+++ /dev/null
@@ -1,22 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.btree.api;
-
-import java.io.Serializable;
-
-public interface IBTreeTupleWriterFactory extends Serializable {
-    public IBTreeTupleWriter createTupleWriter();
-}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IFrameCompressor.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IFrameCompressor.java
index 51e67ca..8e1d0a2 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IFrameCompressor.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IFrameCompressor.java
@@ -15,9 +15,9 @@
 
 package edu.uci.ics.hyracks.storage.am.btree.api;
 
-import edu.uci.ics.hyracks.storage.am.btree.frames.FieldPrefixNSMLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
 public interface IFrameCompressor {
-    public boolean compress(FieldPrefixNSMLeafFrame frame, MultiComparator cmp) throws Exception;
+    public boolean compress(BTreeFieldPrefixNSMLeafFrame frame, MultiComparator cmp) throws Exception;
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IPrefixSlotManager.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IPrefixSlotManager.java
index f45406f..d01db11 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IPrefixSlotManager.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IPrefixSlotManager.java
@@ -16,10 +16,11 @@
 package edu.uci.ics.hyracks.storage.am.btree.api;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.frames.FieldPrefixNSMLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleMode;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleNoExactMatchPolicy;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
 // a slot consists of two fields:
 // first field is 1 byte, it indicates the slot number of a prefix tuple
@@ -42,7 +43,7 @@
 // all prefixes are recomputed during a reorg or compaction
 
 public interface IPrefixSlotManager {
-    public void setFrame(FieldPrefixNSMLeafFrame frame);
+    public void setFrame(BTreeFieldPrefixNSMLeafFrame frame);
 
     public int decodeFirstSlotField(int slot);
 
@@ -50,14 +51,14 @@
 
     public int encodeSlotFields(int firstField, int secondField);
 
-    public int findSlot(ITupleReference searchKey, IBTreeTupleReference frameTuple,
-            IBTreeTupleReference framePrefixTuple, MultiComparator multiCmp, FindTupleMode mode,
+    public int findSlot(ITupleReference searchKey, ITreeIndexTupleReference frameTuple,
+            ITreeIndexTupleReference framePrefixTuple, MultiComparator multiCmp, FindTupleMode mode,
             FindTupleNoExactMatchPolicy matchPolicy);
 
     public int insertSlot(int slot, int tupleOff);
 
     // returns prefix slot number, returns TUPLE_UNCOMPRESSED if none found
-    public int findPrefix(ITupleReference tuple, IBTreeTupleReference framePrefixTuple, MultiComparator multiCmp);
+    public int findPrefix(ITupleReference tuple, ITreeIndexTupleReference framePrefixTuple, MultiComparator multiCmp);
 
     public int getTupleSlotStartOff();
 
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/compressors/FieldPrefixCompressor.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/compressors/FieldPrefixCompressor.java
index eb6c0ab..1292ff2 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/compressors/FieldPrefixCompressor.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/compressors/FieldPrefixCompressor.java
@@ -24,11 +24,11 @@
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
 import edu.uci.ics.hyracks.storage.am.btree.api.IFrameCompressor;
 import edu.uci.ics.hyracks.storage.am.btree.api.IPrefixSlotManager;
-import edu.uci.ics.hyracks.storage.am.btree.frames.FieldPrefixNSMLeafFrame;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrame;
 import edu.uci.ics.hyracks.storage.am.btree.impls.FieldPrefixSlotManager;
 import edu.uci.ics.hyracks.storage.am.btree.impls.FieldPrefixTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriter;
 
 public class FieldPrefixCompressor implements IFrameCompressor {
 
@@ -49,7 +49,7 @@
     }
 
     @Override
-    public boolean compress(FieldPrefixNSMLeafFrame frame, MultiComparator cmp) throws Exception {
+    public boolean compress(BTreeFieldPrefixNSMLeafFrame frame, MultiComparator cmp) throws Exception {
         int tupleCount = frame.getTupleCount();
         if (tupleCount <= 0) {
             frame.setPrefixTupleCount(0);
@@ -365,7 +365,7 @@
     // the prefix length may be different for different keypartitions
     // the occurrenceThreshold determines the minimum number of tuples that must
     // share a common prefix in order for us to consider compressing them
-    private ArrayList<KeyPartition> getKeyPartitions(FieldPrefixNSMLeafFrame frame, MultiComparator cmp,
+    private ArrayList<KeyPartition> getKeyPartitions(BTreeFieldPrefixNSMLeafFrame frame, MultiComparator cmp,
             int occurrenceThreshold) {
         IBinaryComparator[] cmps = cmp.getComparators();
         int fieldCount = cmp.getKeyFieldCount();
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/AbstractBTreeOperatorDescriptor.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/AbstractBTreeOperatorDescriptor.java
deleted file mode 100644
index 35e6951..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/AbstractBTreeOperatorDescriptor.java
+++ /dev/null
@@ -1,92 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
-
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
-import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.job.JobSpecification;
-import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor;
-import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
-
-public abstract class AbstractBTreeOperatorDescriptor extends AbstractSingleActivityOperatorDescriptor {
-
-    private static final long serialVersionUID = 1L;
-
-    protected final IFileSplitProvider fileSplitProvider;
-
-    protected final IBinaryComparatorFactory[] comparatorFactories;
-
-    protected final IBTreeInteriorFrameFactory interiorFrameFactory;
-    protected final IBTreeLeafFrameFactory leafFrameFactory;
-
-    protected final IStorageManagerInterface storageManager;
-    protected final IBTreeRegistryProvider btreeRegistryProvider;
-
-    protected final ITypeTrait[] typeTraits;
-
-    public AbstractBTreeOperatorDescriptor(JobSpecification spec, int inputArity, int outputArity,
-            RecordDescriptor recDesc, IStorageManagerInterface storageManager,
-            IBTreeRegistryProvider btreeRegistryProvider, IFileSplitProvider fileSplitProvider,
-            IBTreeInteriorFrameFactory interiorFactory, IBTreeLeafFrameFactory leafFactory, ITypeTrait[] typeTraits,
-            IBinaryComparatorFactory[] comparatorFactories) {
-        super(spec, inputArity, outputArity);
-        this.fileSplitProvider = fileSplitProvider;
-        this.storageManager = storageManager;
-        this.btreeRegistryProvider = btreeRegistryProvider;
-        this.interiorFrameFactory = interiorFactory;
-        this.leafFrameFactory = leafFactory;
-        this.typeTraits = typeTraits;
-        this.comparatorFactories = comparatorFactories;
-        if (outputArity > 0)
-            recordDescriptors[0] = recDesc;
-    }
-
-    public IFileSplitProvider getFileSplitProvider() {
-        return fileSplitProvider;
-    }
-
-    public IBinaryComparatorFactory[] getComparatorFactories() {
-        return comparatorFactories;
-    }
-
-    public ITypeTrait[] getTypeTraits() {
-        return typeTraits;
-    }
-
-    public IBTreeInteriorFrameFactory getInteriorFactory() {
-        return interiorFrameFactory;
-    }
-
-    public IBTreeLeafFrameFactory getLeafFactory() {
-        return leafFrameFactory;
-    }
-
-    public IStorageManagerInterface getStorageManager() {
-        return storageManager;
-    }
-
-    public IBTreeRegistryProvider getBtreeRegistryProvider() {
-        return btreeRegistryProvider;
-    }
-
-    public RecordDescriptor getRecordDescriptor() {
-        return recordDescriptors[0];
-    }
-}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeBulkLoadOperatorNodePushable.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeBulkLoadOperatorNodePushable.java
deleted file mode 100644
index 6e13ed7..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeBulkLoadOperatorNodePushable.java
+++ /dev/null
@@ -1,95 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
-
-import java.nio.ByteBuffer;
-
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
-import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputSinkOperatorNodePushable;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.frames.MetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
-
-public class BTreeBulkLoadOperatorNodePushable extends
-		AbstractUnaryInputSinkOperatorNodePushable {
-	private float fillFactor;
-	private final BTreeOpHelper btreeOpHelper;
-	private FrameTupleAccessor accessor;
-	private BTree.BulkLoadContext bulkLoadCtx;
-
-	private IRecordDescriptorProvider recordDescProvider;
-
-	private PermutingFrameTupleReference tuple = new PermutingFrameTupleReference();
-
-	public BTreeBulkLoadOperatorNodePushable(
-			AbstractBTreeOperatorDescriptor opDesc,
-			IHyracksStageletContext ctx, int partition, int[] fieldPermutation,
-			float fillFactor, IRecordDescriptorProvider recordDescProvider) {
-		btreeOpHelper = new BTreeOpHelper(opDesc, ctx, partition,
-				BTreeOpHelper.BTreeMode.CREATE_BTREE);
-		this.fillFactor = fillFactor;
-		this.recordDescProvider = recordDescProvider;
-		tuple.setFieldPermutation(fieldPermutation);
-	}
-
-	@Override
-	public void open() throws HyracksDataException {
-		AbstractBTreeOperatorDescriptor opDesc = btreeOpHelper
-				.getOperatorDescriptor();
-		RecordDescriptor recDesc = recordDescProvider.getInputRecordDescriptor(
-				opDesc.getOperatorId(), 0);
-		accessor = new FrameTupleAccessor(btreeOpHelper
-				.getHyracksStageletContext().getFrameSize(), recDesc);
-		IBTreeMetaDataFrame metaFrame = new MetaDataFrame();
-		try {
-			btreeOpHelper.init();
-			btreeOpHelper.getBTree().open(btreeOpHelper.getBTreeFileId());
-			bulkLoadCtx = btreeOpHelper.getBTree().beginBulkLoad(fillFactor,
-					btreeOpHelper.getLeafFrame(),
-					btreeOpHelper.getInteriorFrame(), metaFrame);
-		} catch (Exception e) {
-			// cleanup in case of failure
-			btreeOpHelper.deinit();
-			throw new HyracksDataException(e);
-		}
-	}
-
-	@Override
-	public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
-		accessor.reset(buffer);
-		int tupleCount = accessor.getTupleCount();
-		for (int i = 0; i < tupleCount; i++) {
-			tuple.reset(accessor, i);
-			btreeOpHelper.getBTree().bulkLoadAddTuple(bulkLoadCtx, tuple);
-		}
-	}
-
-	@Override
-	public void close() throws HyracksDataException {
-		try {
-			btreeOpHelper.getBTree().endBulkLoad(bulkLoadCtx);
-		} finally {
-			btreeOpHelper.deinit();
-		}
-	}
-
-	@Override
-	public void flush() throws HyracksDataException {
-	}
-}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDiskOrderScanOperatorDescriptor.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDiskOrderScanOperatorDescriptor.java
deleted file mode 100644
index 17fbf97..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDiskOrderScanOperatorDescriptor.java
+++ /dev/null
@@ -1,47 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
-
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
-import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
-import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
-import edu.uci.ics.hyracks.api.job.JobSpecification;
-import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
-
-public class BTreeDiskOrderScanOperatorDescriptor extends AbstractBTreeOperatorDescriptor {
-
-    private static final long serialVersionUID = 1L;
-
-    public BTreeDiskOrderScanOperatorDescriptor(JobSpecification spec, RecordDescriptor recDesc,
-            IStorageManagerInterface storageManager, IBTreeRegistryProvider btreeRegistryProvider,
-            IFileSplitProvider fileSplitProvider, IBTreeInteriorFrameFactory interiorFactory,
-            IBTreeLeafFrameFactory leafFactory, ITypeTrait[] typeTraits) {
-        super(spec, 0, 1, recDesc, storageManager, btreeRegistryProvider, fileSplitProvider, interiorFactory,
-                leafFactory, typeTraits, null);
-    }
-
-    @Override
-    public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
-            IRecordDescriptorProvider recordDescProvider, int partition, int nPartitions) {
-        return new BTreeDiskOrderScanOperatorNodePushable(this, ctx, partition);
-    }
-}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDiskOrderScanOperatorNodePushable.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDiskOrderScanOperatorNodePushable.java
deleted file mode 100644
index c362183..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDiskOrderScanOperatorNodePushable.java
+++ /dev/null
@@ -1,100 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
-
-import java.io.DataOutput;
-import java.nio.ByteBuffer;
-
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
-import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
-import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryOutputSourceOperatorNodePushable;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.frames.MetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.impls.DiskOrderScanCursor;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
-
-public class BTreeDiskOrderScanOperatorNodePushable extends AbstractUnaryOutputSourceOperatorNodePushable {
-    private final BTreeOpHelper btreeOpHelper;
-
-    public BTreeDiskOrderScanOperatorNodePushable(AbstractBTreeOperatorDescriptor opDesc, IHyracksStageletContext ctx,
-            int partition) {
-        btreeOpHelper = new BTreeOpHelper(opDesc, ctx, partition, BTreeOpHelper.BTreeMode.OPEN_BTREE);
-    }
-
-    @Override
-    public void initialize() throws HyracksDataException {
-
-        IBTreeLeafFrame cursorFrame = btreeOpHelper.getOperatorDescriptor().getLeafFactory().getFrame();
-        DiskOrderScanCursor cursor = new DiskOrderScanCursor(cursorFrame);
-        IBTreeMetaDataFrame metaFrame = new MetaDataFrame();
-
-        try {
-        
-        	btreeOpHelper.init();
-        	
-        	try {
-        		btreeOpHelper.getBTree().diskOrderScan(cursor, cursorFrame, metaFrame);
-
-        		MultiComparator cmp = btreeOpHelper.getBTree().getMultiComparator();
-        		ByteBuffer frame = btreeOpHelper.getHyracksStageletContext().allocateFrame();
-        		FrameTupleAppender appender = new FrameTupleAppender(btreeOpHelper.getHyracksStageletContext().getFrameSize());
-        		appender.reset(frame, true);
-        		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
-        		DataOutput dos = tb.getDataOutput();
-
-        		while (cursor.hasNext()) {
-        			tb.reset();
-        			cursor.next();
-
-        			ITupleReference frameTuple = cursor.getTuple();
-        			for (int i = 0; i < frameTuple.getFieldCount(); i++) {
-        				dos.write(frameTuple.getFieldData(i), frameTuple.getFieldStart(i), frameTuple.getFieldLength(i));
-        				tb.addFieldEndOffset();
-        			}
-
-        			if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
-        				FrameUtils.flushFrame(frame, writer);
-        				appender.reset(frame, true);
-        				if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
-        					throw new IllegalStateException();
-        				}
-        			}
-        		}
-
-        		if (appender.getTupleCount() > 0) {
-        			FrameUtils.flushFrame(frame, writer);
-        		}
-        	}
-        	finally {
-        		cursor.close();
-        		writer.close();
-        	}
-
-        } catch(Exception e) {
-        	deinitialize();
-        	throw new HyracksDataException(e);
-        }
-    }
-
-    @Override
-    public void deinitialize() throws HyracksDataException {
-    	btreeOpHelper.deinit();
-    }
-}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorNodePushable.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorNodePushable.java
deleted file mode 100644
index c087fdd..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorNodePushable.java
+++ /dev/null
@@ -1,104 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
-
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-import edu.uci.ics.hyracks.api.comm.IFrameWriter;
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.api.io.FileReference;
-import edu.uci.ics.hyracks.dataflow.std.base.AbstractOperatorNodePushable;
-import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
-import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
-import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
-
-public class BTreeDropOperatorNodePushable extends AbstractOperatorNodePushable {
-	private static final Logger LOGGER = Logger.getLogger(BTreeDropOperatorNodePushable.class.getName());
-	
-	private final IHyracksStageletContext ctx;
-    private IBTreeRegistryProvider btreeRegistryProvider;
-    private IStorageManagerInterface storageManager;
-    private IFileSplitProvider fileSplitProvider;
-    private int partition;
-
-    public BTreeDropOperatorNodePushable(IHyracksStageletContext ctx, IStorageManagerInterface storageManager,
-            IBTreeRegistryProvider btreeRegistryProvider, IFileSplitProvider fileSplitProvider, int partition) {
-        this.ctx = ctx;
-        this.storageManager = storageManager;
-        this.btreeRegistryProvider = btreeRegistryProvider;
-        this.fileSplitProvider = fileSplitProvider;
-        this.partition = partition;
-    }
-
-    @Override
-    public void deinitialize() throws HyracksDataException {
-    }
-
-    @Override
-    public int getInputArity() {
-        return 0;
-    }
-
-    @Override
-    public IFrameWriter getInputFrameWriter(int index) {
-        return null;
-    }
-
-    @Override
-    public void initialize() throws HyracksDataException {
-    	try {
-
-    		BTreeRegistry btreeRegistry = btreeRegistryProvider.getBTreeRegistry(ctx);
-    		IBufferCache bufferCache = storageManager.getBufferCache(ctx);
-    		IFileMapProvider fileMapProvider = storageManager.getFileMapProvider(ctx);
-
-    		FileReference f = fileSplitProvider.getFileSplits()[partition].getLocalFile();
-
-    		boolean fileIsMapped = fileMapProvider.isMapped(f);
-    		if (!fileIsMapped) {    			    			
-    			throw new HyracksDataException("Cannot drop B-Tree with name " + f.toString() + ". No file mapping exists.");
-    		}
-
-    		int btreeFileId = fileMapProvider.lookupFileId(f);
-
-    		// unregister btree instance
-    		btreeRegistry.lock();
-    		try {
-    			btreeRegistry.unregister(btreeFileId);
-    		} finally {
-    			btreeRegistry.unlock();
-    		}
-
-    		// remove name to id mapping
-    		bufferCache.deleteFile(btreeFileId);
-    	}
-    	// TODO: for the time being we don't throw,
-		// with proper exception handling (no hanging job problem) we should throw
-    	catch (Exception e) {
-    		if (LOGGER.isLoggable(Level.WARNING)) {
-                LOGGER.warning("BTRee Drop Operator Failed Due To Exception: " + e.getMessage());
-            }
-    	}
-    }
-
-    @Override
-    public void setOutputFrameWriter(int index, IFrameWriter writer, RecordDescriptor recordDesc) {
-    }
-}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeFileEnlistmentOperatorDescriptor.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeFileEnlistmentOperatorDescriptor.java
deleted file mode 100644
index c105274..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeFileEnlistmentOperatorDescriptor.java
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
-
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
-import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
-import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
-import edu.uci.ics.hyracks.api.job.JobSpecification;
-import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
-
-// re-create in-memory state for a btree that has already been built (i.e., the file exists):
-// 1. register files in file manager (FileManager)
-// 2. create file mappings (FileMappingProvider)
-// 3. register btree instance (BTreeRegistry)
-
-public class BTreeFileEnlistmentOperatorDescriptor extends AbstractBTreeOperatorDescriptor {
-
-    private static final long serialVersionUID = 1L;
-
-    public BTreeFileEnlistmentOperatorDescriptor(JobSpecification spec, RecordDescriptor recDesc,
-            IStorageManagerInterface storageManager, IBTreeRegistryProvider btreeRegistryProvider,
-            IFileSplitProvider fileSplitProvider, IBTreeInteriorFrameFactory interiorFactory,
-            IBTreeLeafFrameFactory leafFactory, ITypeTrait[] typeTraits, IBinaryComparatorFactory[] comparatorFactories) {
-        super(spec, 0, 0, recDesc, storageManager, btreeRegistryProvider, fileSplitProvider, interiorFactory,
-                leafFactory, typeTraits, comparatorFactories);
-    }
-
-    @Override
-    public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
-            IRecordDescriptorProvider recordDescProvider, int partition, int partitions) throws HyracksDataException {
-        return new BTreeFileEnlistmentOperatorNodePushable(this, ctx, partition);
-    }
-
-}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeInsertUpdateDeleteOperatorNodePushable.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeInsertUpdateDeleteOperatorNodePushable.java
deleted file mode 100644
index acb7d0f..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeInsertUpdateDeleteOperatorNodePushable.java
+++ /dev/null
@@ -1,117 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
-
-import java.nio.ByteBuffer;
-
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
-import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
-import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputUnaryOutputOperatorNodePushable;
-import edu.uci.ics.hyracks.storage.am.btree.frames.MetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
-
-public class BTreeInsertUpdateDeleteOperatorNodePushable extends AbstractUnaryInputUnaryOutputOperatorNodePushable {
-    private final BTreeOpHelper btreeOpHelper;
-    private FrameTupleAccessor accessor;
-    private final IRecordDescriptorProvider recordDescProvider;
-    private final BTreeOp op;
-    private final PermutingFrameTupleReference tuple = new PermutingFrameTupleReference();
-    private ByteBuffer writeBuffer;
-    private BTreeOpContext opCtx;
-
-    public BTreeInsertUpdateDeleteOperatorNodePushable(AbstractBTreeOperatorDescriptor opDesc,
-            IHyracksStageletContext ctx, int partition, int[] fieldPermutation,
-            IRecordDescriptorProvider recordDescProvider, BTreeOp op) {
-        btreeOpHelper = new BTreeOpHelper(opDesc, ctx, partition, BTreeOpHelper.BTreeMode.OPEN_BTREE);
-        this.recordDescProvider = recordDescProvider;
-        this.op = op;
-        tuple.setFieldPermutation(fieldPermutation);
-    }
-
-    @Override
-    public void open() throws HyracksDataException {
-    	AbstractBTreeOperatorDescriptor opDesc = btreeOpHelper.getOperatorDescriptor();
-    	RecordDescriptor inputRecDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getOperatorId(), 0);
-    	accessor = new FrameTupleAccessor(btreeOpHelper.getHyracksStageletContext().getFrameSize(), inputRecDesc);
-    	writeBuffer = btreeOpHelper.getHyracksStageletContext().allocateFrame();
-    	try {
-    		btreeOpHelper.init();
-    		btreeOpHelper.getBTree().open(btreeOpHelper.getBTreeFileId());
-    		opCtx = btreeOpHelper.getBTree().createOpContext(op, btreeOpHelper.getLeafFrame(),
-    				btreeOpHelper.getInteriorFrame(), new MetaDataFrame());
-    	} catch(Exception e) {
-    		// cleanup in case of failure
-    		btreeOpHelper.deinit();
-    		throw new HyracksDataException(e);
-    	}
-    }
-
-    @Override
-    public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
-        final BTree btree = btreeOpHelper.getBTree();
-        accessor.reset(buffer);
-
-        int tupleCount = accessor.getTupleCount();
-        for (int i = 0; i < tupleCount; i++) {
-            tuple.reset(accessor, i);
-            try {
-                switch (op) {
-
-                    case BTO_INSERT: {
-                        btree.insert(tuple, opCtx);
-                    }
-                        break;
-
-                    case BTO_DELETE: {
-                        btree.delete(tuple, opCtx);
-                    }
-                        break;
-
-                    default: {
-                        throw new HyracksDataException("Unsupported operation " + op
-                                + " in BTree InsertUpdateDelete operator");
-                    }
-
-                }
-
-            } catch (Exception e) {
-                e.printStackTrace();
-            }
-        }
-
-        // pass a copy of the frame to next op
-        System.arraycopy(buffer.array(), 0, writeBuffer.array(), 0, buffer.capacity());
-        FrameUtils.flushFrame(writeBuffer, writer);
-    }
-
-    @Override
-    public void close() throws HyracksDataException {
-        try {
-            writer.close();
-        } finally {
-            btreeOpHelper.deinit();
-        }
-    }
-
-    @Override
-    public void flush() throws HyracksDataException {
-    }
-}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeOpHelper.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeOpHelper.java
index 880cc25..c85c6a0 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeOpHelper.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeOpHelper.java
@@ -1,161 +1,32 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
 package edu.uci.ics.hyracks.storage.am.btree.dataflow;
 
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.api.io.FileReference;
-import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.frames.MetaDataFrame;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOperatorDescriptorHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexHelperOpenMode;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexOpHelper;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.freepage.LinkedListFreePageManager;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
-import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
 
-final class BTreeOpHelper {
+public class BTreeOpHelper extends TreeIndexOpHelper {
 
-	public enum BTreeMode {
-		OPEN_BTREE, CREATE_BTREE, ENLIST_BTREE
-	}
-	
-	private IBTreeInteriorFrame interiorFrame;
-	private IBTreeLeafFrame leafFrame;
-
-	private BTree btree;
-	private int btreeFileId = -1;
-	private int partition;
-
-    private AbstractBTreeOperatorDescriptor opDesc;
-    private IHyracksStageletContext ctx;
-
-	private BTreeMode mode;
-
-    BTreeOpHelper(AbstractBTreeOperatorDescriptor opDesc, final IHyracksStageletContext ctx, int partition,
-            BTreeMode mode) {
-        this.opDesc = opDesc;
-        this.ctx = ctx;
-        this.mode = mode;
-        this.partition = partition;
+    public BTreeOpHelper(ITreeIndexOperatorDescriptorHelper opDesc, IHyracksStageletContext ctx, int partition,
+            IndexHelperOpenMode mode) {
+        super(opDesc, ctx, partition, mode);
     }
-
-	void init() throws HyracksDataException {
+    
+    public ITreeIndex createTreeIndex() throws HyracksDataException {
         IBufferCache bufferCache = opDesc.getStorageManager().getBufferCache(ctx);
-        IFileMapProvider fileMapProvider = opDesc.getStorageManager().getFileMapProvider(ctx);
-        IFileSplitProvider fileSplitProvider = opDesc.getFileSplitProvider();
-
-        FileReference f = fileSplitProvider.getFileSplits()[partition].getLocalFile();
-        boolean fileIsMapped = fileMapProvider.isMapped(f);
-
-		switch (mode) {
-		
-		case OPEN_BTREE: {
-			if (!fileIsMapped) {
-				throw new HyracksDataException(
-						"Trying to open btree from unmapped file " + f.toString());
-			}
-		}
-		break;
-
-		case CREATE_BTREE:
-		case ENLIST_BTREE: {
-			if (!fileIsMapped) {
-				bufferCache.createFile(f);
-			}
-		}
-		break;
-		
-		}
-
-        btreeFileId = fileMapProvider.lookupFileId(f);
-        bufferCache.openFile(btreeFileId);
-
-		interiorFrame = opDesc.getInteriorFactory().getFrame();
-		leafFrame = opDesc.getLeafFactory().getFrame();
-
-        BTreeRegistry btreeRegistry = opDesc.getBtreeRegistryProvider().getBTreeRegistry(ctx);
-        btree = btreeRegistry.get(btreeFileId);
-        if (btree == null) {
-
-			// create new btree and register it
-			btreeRegistry.lock();
-			try {
-				// check if btree has already been registered by another thread
-				btree = btreeRegistry.get(btreeFileId);
-				if (btree == null) {
-					// this thread should create and register the btree
-
-					IBinaryComparator[] comparators = new IBinaryComparator[opDesc
-							.getComparatorFactories().length];
-					for (int i = 0; i < opDesc.getComparatorFactories().length; i++) {
-						comparators[i] = opDesc.getComparatorFactories()[i]
-								.createBinaryComparator();
-					}
-
-					MultiComparator cmp = new MultiComparator(opDesc
-							.getTypeTraits(), comparators);
-
-					btree = new BTree(bufferCache, opDesc.getInteriorFactory(),
-							opDesc.getLeafFactory(), cmp);
-					if (mode == BTreeMode.CREATE_BTREE) {
-						MetaDataFrame metaFrame = new MetaDataFrame();
-						try {
-							btree.create(btreeFileId, leafFrame, metaFrame);
-							btree.open(btreeFileId);
-						} catch (Exception e) {
-							throw new HyracksDataException(e);
-						}
-					}
-					btreeRegistry.register(btreeFileId, btree);
-				}
-			} finally {
-				btreeRegistry.unlock();
-			}
-		}
-	}
-
-    public void deinit() throws HyracksDataException {
-        if (btreeFileId != -1) {
-            IBufferCache bufferCache = opDesc.getStorageManager().getBufferCache(ctx);
-            bufferCache.closeFile(btreeFileId);
-        }
+        ITreeIndexMetaDataFrameFactory metaDataFrameFactory = new LIFOMetaDataFrameFactory();
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, indexFileId, 0, metaDataFrameFactory);
+        return new BTree(bufferCache, freePageManager, opDesc.getTreeIndexInteriorFactory(),
+                opDesc.getTreeIndexLeafFactory(), cmp);
     }
-
-	public BTree getBTree() {
-		return btree;
-	}
-
-    public IHyracksStageletContext getHyracksStageletContext() {
-        return ctx;
-    }
-
-	public AbstractBTreeOperatorDescriptor getOperatorDescriptor() {
-		return opDesc;
-	}
-
-	public IBTreeLeafFrame getLeafFrame() {
-		return leafFrame;
-	}
-
-	public IBTreeInteriorFrame getInteriorFrame() {
-		return interiorFrame;
-	}
-
-	public int getBTreeFileId() {
-		return btreeFileId;
-	}
-}
\ No newline at end of file
+    
+    
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeOpHelperFactory.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeOpHelperFactory.java
new file mode 100644
index 0000000..7802b81
--- /dev/null
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeOpHelperFactory.java
@@ -0,0 +1,24 @@
+package edu.uci.ics.hyracks.storage.am.btree.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOperatorDescriptorHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexHelperOpenMode;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexOpHelper;
+import edu.uci.ics.hyracks.storage.am.common.impls.TreeDiskOrderScanCursor;
+
+public class BTreeOpHelperFactory implements ITreeIndexOpHelperFactory {
+
+    private static final long serialVersionUID = 1L;
+
+    @Override
+    public TreeIndexOpHelper createTreeIndexOpHelper(ITreeIndexOperatorDescriptorHelper opDesc,
+            IHyracksStageletContext ctx, int partition, IndexHelperOpenMode mode) {
+        return new BTreeOpHelper(opDesc, ctx, partition, mode);
+    }
+
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorDescriptor.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorDescriptor.java
index 21f37a3..254935b 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorDescriptor.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorDescriptor.java
@@ -24,11 +24,14 @@
 import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
 import edu.uci.ics.hyracks.api.job.JobSpecification;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
-public class BTreeSearchOperatorDescriptor extends AbstractBTreeOperatorDescriptor {
+public class BTreeSearchOperatorDescriptor extends AbstractTreeIndexOperatorDescriptor {
 
     private static final long serialVersionUID = 1L;
 
@@ -40,13 +43,13 @@
     private boolean highKeyInclusive;
 
     public BTreeSearchOperatorDescriptor(JobSpecification spec, RecordDescriptor recDesc,
-            IStorageManagerInterface storageManager, IBTreeRegistryProvider btreeRegistryProvider,
-            IFileSplitProvider fileSplitProvider, IBTreeInteriorFrameFactory interiorFactory,
-            IBTreeLeafFrameFactory leafFactory, ITypeTrait[] typeTraits,
+            IStorageManagerInterface storageManager, IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider,
+            IFileSplitProvider fileSplitProvider, ITreeIndexFrameFactory interiorFrameFactory,
+            ITreeIndexFrameFactory leafFrameFactory, ITypeTrait[] typeTraits,
             IBinaryComparatorFactory[] comparatorFactories, boolean isForward, int[] lowKeyFields, int[] highKeyFields,
-            boolean lowKeyInclusive, boolean highKeyInclusive) {
-        super(spec, 1, 1, recDesc, storageManager, btreeRegistryProvider, fileSplitProvider, interiorFactory,
-                leafFactory, typeTraits, comparatorFactories);
+            boolean lowKeyInclusive, boolean highKeyInclusive, ITreeIndexOpHelperFactory opHelperFactory) {
+        super(spec, 1, 1, recDesc, storageManager, treeIndexRegistryProvider, fileSplitProvider, interiorFrameFactory,
+                leafFrameFactory, typeTraits, comparatorFactories, opHelperFactory);
         this.isForward = isForward;
         this.lowKeyFields = lowKeyFields;
         this.highKeyFields = highKeyFields;
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorNodePushable.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorNodePushable.java
index 415f169..9d33bb2 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorNodePushable.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeSearchOperatorNodePushable.java
@@ -28,203 +28,187 @@
 import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputUnaryOutputOperatorNodePushable;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeCursor;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
 import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
-import edu.uci.ics.hyracks.storage.am.btree.impls.RangeSearchCursor;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeRangeSearchCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexHelperOpenMode;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.PermutingFrameTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexOpHelper;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
-public class BTreeSearchOperatorNodePushable extends
-		AbstractUnaryInputUnaryOutputOperatorNodePushable {
-	private BTreeOpHelper btreeOpHelper;
-	private FrameTupleAccessor accessor;
+public class BTreeSearchOperatorNodePushable extends AbstractUnaryInputUnaryOutputOperatorNodePushable {
+    private TreeIndexOpHelper treeIndexOpHelper;
+    private FrameTupleAccessor accessor;
 
-	private ByteBuffer writeBuffer;
-	private FrameTupleAppender appender;
-	private ArrayTupleBuilder tb;
-	private DataOutput dos;
+    private ByteBuffer writeBuffer;
+    private FrameTupleAppender appender;
+    private ArrayTupleBuilder tb;
+    private DataOutput dos;
 
-	private BTree btree;
-	private boolean isForward;
-	private PermutingFrameTupleReference lowKey;
-	private PermutingFrameTupleReference highKey;
-	private boolean lowKeyInclusive;
-	private boolean highKeyInclusive;
-	private RangePredicate rangePred;
-	private MultiComparator lowKeySearchCmp;
-	private MultiComparator highKeySearchCmp;
-	private IBTreeCursor cursor;
-	private IBTreeLeafFrame cursorFrame;
-	private BTreeOpContext opCtx;
+    private BTree btree;
+    private boolean isForward;
+    private PermutingFrameTupleReference lowKey;
+    private PermutingFrameTupleReference highKey;
+    private boolean lowKeyInclusive;
+    private boolean highKeyInclusive;
+    private RangePredicate rangePred;
+    private MultiComparator lowKeySearchCmp;
+    private MultiComparator highKeySearchCmp;
+    private ITreeIndexCursor cursor;
+    private ITreeIndexFrame cursorFrame;
+    private BTreeOpContext opCtx;
 
-	private RecordDescriptor recDesc;
+    private RecordDescriptor recDesc;
 
-	public BTreeSearchOperatorNodePushable(
-			AbstractBTreeOperatorDescriptor opDesc,
-			IHyracksStageletContext ctx, int partition,
-			IRecordDescriptorProvider recordDescProvider, boolean isForward,
-			int[] lowKeyFields, int[] highKeyFields, boolean lowKeyInclusive,
-			boolean highKeyInclusive) {
-		btreeOpHelper = new BTreeOpHelper(opDesc, ctx, partition,
-				BTreeOpHelper.BTreeMode.OPEN_BTREE);
-		this.isForward = isForward;
-		this.lowKeyInclusive = lowKeyInclusive;
-		this.highKeyInclusive = highKeyInclusive;
-		this.recDesc = recordDescProvider.getInputRecordDescriptor(opDesc
-				.getOperatorId(), 0);
-		if (lowKeyFields != null && lowKeyFields.length > 0) {
-			lowKey = new PermutingFrameTupleReference();
-			lowKey.setFieldPermutation(lowKeyFields);
-		}
-		if (highKeyFields != null && highKeyFields.length > 0) {
-			highKey = new PermutingFrameTupleReference();
-			highKey.setFieldPermutation(highKeyFields);
-		}
-	}
+    public BTreeSearchOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc, IHyracksStageletContext ctx,
+            int partition, IRecordDescriptorProvider recordDescProvider, boolean isForward, int[] lowKeyFields,
+            int[] highKeyFields, boolean lowKeyInclusive, boolean highKeyInclusive) {
+        treeIndexOpHelper = opDesc.getTreeIndexOpHelperFactory().createTreeIndexOpHelper(opDesc, ctx, partition, IndexHelperOpenMode.OPEN);
+        this.isForward = isForward;
+        this.lowKeyInclusive = lowKeyInclusive;
+        this.highKeyInclusive = highKeyInclusive;
+        this.recDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getOperatorId(), 0);
+        if (lowKeyFields != null && lowKeyFields.length > 0) {
+            lowKey = new PermutingFrameTupleReference();
+            lowKey.setFieldPermutation(lowKeyFields);
+        }
+        if (highKeyFields != null && highKeyFields.length > 0) {
+            highKey = new PermutingFrameTupleReference();
+            highKey.setFieldPermutation(highKeyFields);
+        }
+    }
 
-	@Override
-	public void open() throws HyracksDataException {
-		AbstractBTreeOperatorDescriptor opDesc = btreeOpHelper
-				.getOperatorDescriptor();
-		accessor = new FrameTupleAccessor(btreeOpHelper
-				.getHyracksStageletContext().getFrameSize(), recDesc);
+    @Override
+    public void open() throws HyracksDataException {
+        AbstractTreeIndexOperatorDescriptor opDesc = (AbstractTreeIndexOperatorDescriptor) treeIndexOpHelper
+                .getOperatorDescriptor();
+        accessor = new FrameTupleAccessor(treeIndexOpHelper.getHyracksStageletContext().getFrameSize(), recDesc);
 
-		cursorFrame = opDesc.getLeafFactory().getFrame();
-		cursor = new RangeSearchCursor(cursorFrame);
+        cursorFrame = opDesc.getTreeIndexLeafFactory().createFrame();
+        cursor = new BTreeRangeSearchCursor((IBTreeLeafFrame)cursorFrame);
 
-		try {
+        try {
 
-			btreeOpHelper.init();
-			btree = btreeOpHelper.getBTree();
+            treeIndexOpHelper.init();
+            btree = (BTree)treeIndexOpHelper.getTreeIndex();
 
-			// construct range predicate
+            // construct range predicate
 
-			int lowKeySearchFields = btree.getMultiComparator()
-					.getComparators().length;
-			int highKeySearchFields = btree.getMultiComparator()
-					.getComparators().length;
-			if (lowKey != null)
-				lowKeySearchFields = lowKey.getFieldCount();
-			if (highKey != null)
-				highKeySearchFields = highKey.getFieldCount();
+            int lowKeySearchFields = btree.getMultiComparator().getComparators().length;
+            int highKeySearchFields = btree.getMultiComparator().getComparators().length;
+            if (lowKey != null)
+                lowKeySearchFields = lowKey.getFieldCount();
+            if (highKey != null)
+                highKeySearchFields = highKey.getFieldCount();
 
-			IBinaryComparator[] lowKeySearchComparators = new IBinaryComparator[lowKeySearchFields];
-			for (int i = 0; i < lowKeySearchFields; i++) {
-				lowKeySearchComparators[i] = btree.getMultiComparator()
-						.getComparators()[i];
-			}
-			lowKeySearchCmp = new MultiComparator(btree.getMultiComparator()
-					.getTypeTraits(), lowKeySearchComparators);
+            IBinaryComparator[] lowKeySearchComparators = new IBinaryComparator[lowKeySearchFields];
+            for (int i = 0; i < lowKeySearchFields; i++) {
+                lowKeySearchComparators[i] = btree.getMultiComparator().getComparators()[i];
+            }
+            lowKeySearchCmp = new MultiComparator(btree.getMultiComparator().getTypeTraits(), lowKeySearchComparators);
 
-			if (lowKeySearchFields == highKeySearchFields) {
-				highKeySearchCmp = lowKeySearchCmp;
-			} else {
-				IBinaryComparator[] highKeySearchComparators = new IBinaryComparator[highKeySearchFields];
-				for (int i = 0; i < highKeySearchFields; i++) {
-					highKeySearchComparators[i] = btree.getMultiComparator()
-							.getComparators()[i];
-				}
-				highKeySearchCmp = new MultiComparator(btree
-						.getMultiComparator().getTypeTraits(),
-						highKeySearchComparators);
+            if (lowKeySearchFields == highKeySearchFields) {
+                highKeySearchCmp = lowKeySearchCmp;
+            } else {
+                IBinaryComparator[] highKeySearchComparators = new IBinaryComparator[highKeySearchFields];
+                for (int i = 0; i < highKeySearchFields; i++) {
+                    highKeySearchComparators[i] = btree.getMultiComparator().getComparators()[i];
+                }
+                highKeySearchCmp = new MultiComparator(btree.getMultiComparator().getTypeTraits(),
+                        highKeySearchComparators);
 
-			}
+            }
 
-			rangePred = new RangePredicate(isForward, null, null,
-					lowKeyInclusive, highKeyInclusive, lowKeySearchCmp,
-					highKeySearchCmp);
+            rangePred = new RangePredicate(isForward, null, null, lowKeyInclusive, highKeyInclusive, lowKeySearchCmp,
+                    highKeySearchCmp);
 
-			accessor = new FrameTupleAccessor(btreeOpHelper
-					.getHyracksStageletContext().getFrameSize(), recDesc);
+            accessor = new FrameTupleAccessor(treeIndexOpHelper.getHyracksStageletContext().getFrameSize(), recDesc);
 
-			writeBuffer = btreeOpHelper.getHyracksStageletContext()
-					.allocateFrame();
-			tb = new ArrayTupleBuilder(btree.getMultiComparator()
-					.getFieldCount());
-			dos = tb.getDataOutput();
-			appender = new FrameTupleAppender(btreeOpHelper
-					.getHyracksStageletContext().getFrameSize());
-			appender.reset(writeBuffer, true);
+            writeBuffer = treeIndexOpHelper.getHyracksStageletContext().allocateFrame();
+            tb = new ArrayTupleBuilder(btree.getMultiComparator().getFieldCount());
+            dos = tb.getDataOutput();
+            appender = new FrameTupleAppender(treeIndexOpHelper.getHyracksStageletContext().getFrameSize());
+            appender.reset(writeBuffer, true);
 
-			opCtx = btree.createOpContext(BTreeOp.BTO_SEARCH, btreeOpHelper
-					.getLeafFrame(), btreeOpHelper.getInteriorFrame(), null);
+            opCtx = btree.createOpContext(IndexOp.SEARCH, treeIndexOpHelper.getLeafFrame(), treeIndexOpHelper
+                    .getInteriorFrame(), null);
 
-		} catch (Exception e) {
-			btreeOpHelper.deinit();
-		}
-	}
+        } catch (Exception e) {
+            treeIndexOpHelper.deinit();
+        }
+    }
 
-	private void writeSearchResults() throws Exception {
-		while (cursor.hasNext()) {
-			tb.reset();
-			cursor.next();
+    private void writeSearchResults() throws Exception {
+        while (cursor.hasNext()) {
+            tb.reset();
+            cursor.next();
 
-			ITupleReference frameTuple = cursor.getTuple();
-			for (int i = 0; i < frameTuple.getFieldCount(); i++) {
-				dos.write(frameTuple.getFieldData(i), frameTuple
-						.getFieldStart(i), frameTuple.getFieldLength(i));
-				tb.addFieldEndOffset();
-			}
+            ITupleReference frameTuple = cursor.getTuple();
+            for (int i = 0; i < frameTuple.getFieldCount(); i++) {
+                dos.write(frameTuple.getFieldData(i), frameTuple.getFieldStart(i), frameTuple.getFieldLength(i));
+                tb.addFieldEndOffset();
+            }
 
-			if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0,
-					tb.getSize())) {
-				FrameUtils.flushFrame(writeBuffer, writer);
-				appender.reset(writeBuffer, true);
-				if (!appender.append(tb.getFieldEndOffsets(),
-						tb.getByteArray(), 0, tb.getSize())) {
-					throw new IllegalStateException();
-				}
-			}
-		}
-	}
+            if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
+                FrameUtils.flushFrame(writeBuffer, writer);
+                appender.reset(writeBuffer, true);
+                if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
+                    throw new IllegalStateException();
+                }
+            }
+        }
+    }
 
-	@Override
-	public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
-		accessor.reset(buffer);
+    @Override
+    public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
+        accessor.reset(buffer);
 
-		int tupleCount = accessor.getTupleCount();
-		try {
-			for (int i = 0; i < tupleCount; i++) {
-				if (lowKey != null)
-					lowKey.reset(accessor, i);
-				if (highKey != null)
-					highKey.reset(accessor, i);
-				rangePred.setLowKey(lowKey, lowKeyInclusive);
-				rangePred.setHighKey(highKey, highKeyInclusive);
+        int tupleCount = accessor.getTupleCount();
+        try {
+            for (int i = 0; i < tupleCount; i++) {
+                if (lowKey != null)
+                    lowKey.reset(accessor, i);
+                if (highKey != null)
+                    highKey.reset(accessor, i);
+                rangePred.setLowKey(lowKey, lowKeyInclusive);
+                rangePred.setHighKey(highKey, highKeyInclusive);
 
-				cursor.reset();
-				btree.search(cursor, rangePred, opCtx);
-				writeSearchResults();
-			}
-		} catch (Exception e) {
-			throw new HyracksDataException(e);
-		}
-	}
+                cursor.reset();
+                btree.search(cursor, rangePred, opCtx);
+                writeSearchResults();
+            }
+        } catch (Exception e) {
+            throw new HyracksDataException(e);
+        }
+    }
 
-	@Override
-	public void close() throws HyracksDataException {
-		try {
-			if (appender.getTupleCount() > 0) {
-				FrameUtils.flushFrame(writeBuffer, writer);
-			}
-			writer.close();
-			try {
-				cursor.close();
-			} catch (Exception e) {
-				throw new HyracksDataException(e);
-			}
-		} finally {
-			btreeOpHelper.deinit();
-		}
-	}
+    @Override
+    public void close() throws HyracksDataException {
+        try {
+            if (appender.getTupleCount() > 0) {
+                FrameUtils.flushFrame(writeBuffer, writer);
+            }
+            writer.close();
+            try {
+                cursor.close();
+            } catch (Exception e) {
+                throw new HyracksDataException(e);
+            }
+        } finally {
+            treeIndexOpHelper.deinit();
+        }
+    }
 
-	@Override
-	public void flush() throws HyracksDataException {
-		if (appender.getTupleCount() > 0) {
-			FrameUtils.flushFrame(writeBuffer, writer);
-		}
-	}
+    @Override
+    public void flush() throws HyracksDataException {
+        if (appender.getTupleCount() > 0) {
+            FrameUtils.flushFrame(writeBuffer, writer);
+        }
+    }
 }
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/FieldPrefixNSMLeafFrame.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrame.java
similarity index 89%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/FieldPrefixNSMLeafFrame.java
rename to hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrame.java
index 6eeb5e1..bd4947c 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/FieldPrefixNSMLeafFrame.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrame.java
@@ -26,30 +26,30 @@
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
 import edu.uci.ics.hyracks.storage.am.btree.api.IFrameCompressor;
 import edu.uci.ics.hyracks.storage.am.btree.api.IPrefixSlotManager;
-import edu.uci.ics.hyracks.storage.am.btree.api.ISlotManager;
 import edu.uci.ics.hyracks.storage.am.btree.compressors.FieldPrefixCompressor;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeException;
 import edu.uci.ics.hyracks.storage.am.btree.impls.FieldPrefixPrefixTupleReference;
 import edu.uci.ics.hyracks.storage.am.btree.impls.FieldPrefixSlotManager;
 import edu.uci.ics.hyracks.storage.am.btree.impls.FieldPrefixTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleMode;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleNoExactMatchPolicy;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SlotOffTupleOff;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SpaceStatus;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SplitKey;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.api.ISlotManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.frames.FrameOpSpaceStatus;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.SlotOffTupleOff;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriter;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 
 // WARNING: only works when tupleWriter is an instance of TypeAwareTupleWriter
 
-public class FieldPrefixNSMLeafFrame implements IBTreeLeafFrame {
+public class BTreeFieldPrefixNSMLeafFrame implements IBTreeLeafFrame {
 
     protected static final int pageLsnOff = 0; // 0
     protected static final int tupleCountOff = pageLsnOff + 4; // 4
@@ -69,12 +69,12 @@
     public IPrefixSlotManager slotManager; // TODO: should be protected, but
     // will trigger some refactoring
 
-    private IBTreeTupleWriter tupleWriter;
+    private ITreeIndexTupleWriter tupleWriter;
 
     private FieldPrefixTupleReference frameTuple;
     private FieldPrefixPrefixTupleReference framePrefixTuple;
 
-    public FieldPrefixNSMLeafFrame(IBTreeTupleWriter tupleWriter) {
+    public BTreeFieldPrefixNSMLeafFrame(ITreeIndexTupleWriter tupleWriter) {
         this.tupleWriter = tupleWriter;
         this.frameTuple = new FieldPrefixTupleReference(tupleWriter.createTupleReference());
         ITypeTrait[] typeTraits = ((TypeAwareTupleWriter) tupleWriter).getTypeTraits();
@@ -115,7 +115,7 @@
     // 3. prefix tuple are sorted (last prefix tuple is at highest offset)
     // this procedure will not move prefix tuples
     @Override
-    public void compact(MultiComparator cmp) {
+    public boolean compact(MultiComparator cmp) {
         resetSpaceParams();
 
         frameTuple.setFieldCount(cmp.getFieldCount());
@@ -168,11 +168,13 @@
             slotManager.setSlot(sortedTupleOffs.get(i).slotOff, slotManager.encodeSlotFields(prefixSlotNum, freeSpace));
             freeSpace += tupleLength;
         }
-
+        
         buf.putInt(freeSpaceOff, freeSpace);
         int totalFreeSpace = buf.capacity() - buf.getInt(freeSpaceOff)
                 - ((buf.getInt(tupleCountOff) + buf.getInt(prefixTupleCountOff)) * slotManager.getSlotSize());
         buf.putInt(totalFreeSpaceOff, totalFreeSpace);
+        
+        return false;
     }
 
     @Override
@@ -225,7 +227,7 @@
     }
 
     @Override
-    public SpaceStatus hasSpaceInsert(ITupleReference tuple, MultiComparator cmp) {
+    public FrameOpSpaceStatus hasSpaceInsert(ITupleReference tuple, MultiComparator cmp) {
         int freeContiguous = buf.capacity() - buf.getInt(freeSpaceOff)
                 - ((buf.getInt(tupleCountOff) + buf.getInt(prefixTupleCountOff)) * slotManager.getSlotSize());
 
@@ -233,11 +235,11 @@
 
         // see if the tuple would fit uncompressed
         if (bytesRequired + slotManager.getSlotSize() <= freeContiguous)
-            return SpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE;
+            return FrameOpSpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE;
 
         // see if tuple would fit into remaining space after compaction
         if (bytesRequired + slotManager.getSlotSize() <= buf.getInt(totalFreeSpaceOff))
-            return SpaceStatus.SUFFICIENT_SPACE;
+            return FrameOpSpaceStatus.SUFFICIENT_SPACE;
 
         // see if the tuple matches a prefix and will fit after truncating the
         // prefix
@@ -250,16 +252,16 @@
             int compressedSize = tupleWriter.bytesRequired(tuple, numPrefixFields, tuple.getFieldCount()
                     - numPrefixFields);
             if (compressedSize + slotManager.getSlotSize() <= freeContiguous)
-                return SpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE;
+                return FrameOpSpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE;
         }
 
-        return SpaceStatus.INSUFFICIENT_SPACE;
+        return FrameOpSpaceStatus.INSUFFICIENT_SPACE;
     }
 
     @Override
-    public SpaceStatus hasSpaceUpdate(int rid, ITupleReference tuple, MultiComparator cmp) {
+    public FrameOpSpaceStatus hasSpaceUpdate(int rid, ITupleReference tuple, MultiComparator cmp) {
         // TODO Auto-generated method stub
-        return SpaceStatus.INSUFFICIENT_SPACE;
+        return FrameOpSpaceStatus.INSUFFICIENT_SPACE;
     }
 
     protected void resetSpaceParams() {
@@ -290,12 +292,14 @@
     }
 
     @Override
-    public void insert(ITupleReference tuple, MultiComparator cmp) throws Exception {
-        int slot = slotManager.findSlot(tuple, frameTuple, framePrefixTuple, cmp, FindTupleMode.FTM_INCLUSIVE,
-                FindTupleNoExactMatchPolicy.FTP_HIGHER_KEY);
-
-        slot = slotManager.insertSlot(slot, buf.getInt(freeSpaceOff));
-
+    public int findTupleIndex(ITupleReference tuple, MultiComparator cmp) throws Exception {
+    	return slotManager.findSlot(tuple, frameTuple, framePrefixTuple, cmp, FindTupleMode.FTM_INCLUSIVE,
+    			FindTupleNoExactMatchPolicy.FTP_HIGHER_KEY);
+    }
+    
+    @Override
+    public void insert(ITupleReference tuple, MultiComparator cmp, int tupleIndex) throws Exception {        
+        int slot = slotManager.insertSlot(tupleIndex, buf.getInt(freeSpaceOff));
         int prefixSlotNum = slotManager.decodeFirstSlotField(slot);
         int numPrefixFields = 0;
         if (prefixSlotNum != FieldPrefixSlotManager.TUPLE_UNCOMPRESSED) {
@@ -382,6 +386,11 @@
     public boolean isLeaf() {
         return buf.get(levelOff) == 0;
     }
+    
+    @Override
+    public boolean isInterior() {
+        return buf.get(levelOff) > 0;
+    }
 
     @Override
     public byte getLevel() {
@@ -446,31 +455,20 @@
     }
 
     @Override
-    public int split(IBTreeFrame rightFrame, ITupleReference tuple, MultiComparator cmp, SplitKey splitKey)
+    public int split(ITreeIndexFrame rightFrame, ITupleReference tuple, MultiComparator cmp, ISplitKey splitKey)
             throws Exception {
 
-        FieldPrefixNSMLeafFrame rf = (FieldPrefixNSMLeafFrame) rightFrame;
+        BTreeFieldPrefixNSMLeafFrame rf = (BTreeFieldPrefixNSMLeafFrame) rightFrame;
 
         frameTuple.setFieldCount(cmp.getFieldCount());
-
-        // before doing anything check if key already exists
-        int slot = slotManager.findSlot(tuple, frameTuple, framePrefixTuple, cmp, FindTupleMode.FTM_EXACT,
-                FindTupleNoExactMatchPolicy.FTP_HIGHER_KEY);
-        int tupleSlotNum = slotManager.decodeSecondSlotField(slot);
-        if (tupleSlotNum != FieldPrefixSlotManager.GREATEST_SLOT) {
-            frameTuple.resetByTupleIndex(this, tupleSlotNum);
-            if (cmp.compare(tuple, frameTuple) == 0) {
-                throw new BTreeException("Inserting duplicate key into unique index");
-            }
-        }
-
+        
         ByteBuffer right = rf.getBuffer();
         int tupleCount = getTupleCount();
         int prefixTupleCount = getPrefixTupleCount();
 
         int tuplesToLeft;
         int midSlotNum = tupleCount / 2;
-        IBTreeFrame targetFrame = null;
+        ITreeIndexFrame targetFrame = null;
         frameTuple.resetByTupleIndex(this, midSlotNum);
         int comparison = cmp.compare(tuple, frameTuple);
         if (comparison >= 0) {
@@ -573,7 +571,8 @@
         rightFrame.compact(cmp);
 
         // insert last key
-        targetFrame.insert(tuple, cmp);
+        int targetTupleIndex = targetFrame.findTupleIndex(tuple, cmp);
+        targetFrame.insert(tuple, cmp, targetTupleIndex);
 
         // set split key to be highest value in left page
         frameTuple.resetByTupleIndex(this, getTupleCount() - 1);
@@ -581,7 +580,7 @@
         int splitKeySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
         splitKey.initData(splitKeySize);
         tupleWriter.writeTupleFields(frameTuple, 0, cmp.getKeyFieldCount(), splitKey.getBuffer(), 0);
-        splitKey.getTuple().resetByOffset(splitKey.getBuffer(), 0);
+        splitKey.getTuple().resetByTupleOffset(splitKey.getBuffer(), 0);
 
         return 0;
     }
@@ -638,17 +637,17 @@
         frameTuple.setFieldCount(fieldCount);
     }
 
-    public IBTreeTupleWriter getTupleWriter() {
+    public ITreeIndexTupleWriter getTupleWriter() {
         return tupleWriter;
     }
 
     @Override
-    public IBTreeTupleReference createTupleReference() {
+    public ITreeIndexTupleReference createTupleReference() {
         return new FieldPrefixTupleReference(tupleWriter.createTupleReference());
     }
 
     @Override
-    public int findTupleIndex(ITupleReference searchKey, IBTreeTupleReference pageTuple, MultiComparator cmp,
+    public int findTupleIndex(ITupleReference searchKey, ITreeIndexTupleReference pageTuple, MultiComparator cmp,
             FindTupleMode ftm, FindTupleNoExactMatchPolicy ftp) {
         int slot = slotManager.findSlot(searchKey, pageTuple, framePrefixTuple, cmp, ftm, ftp);
         int tupleIndex = slotManager.decodeSecondSlotField(slot);
@@ -658,4 +657,8 @@
             return tupleIndex;
     }
 
+    @Override
+	public int getPageHeaderSize() {
+		return nextLeafOff;
+	}
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMLeafFrameFactory.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrameFactory.java
similarity index 63%
copy from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMLeafFrameFactory.java
copy to hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrameFactory.java
index 202f31a..05b43d3 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMLeafFrameFactory.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeFieldPrefixNSMLeafFrameFactory.java
@@ -16,20 +16,20 @@
 package edu.uci.ics.hyracks.storage.am.btree.frames;
 
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriterFactory;
 
-public class NSMLeafFrameFactory implements IBTreeLeafFrameFactory {
+public class BTreeFieldPrefixNSMLeafFrameFactory implements ITreeIndexFrameFactory {
 
     private static final long serialVersionUID = 1L;
-    private IBTreeTupleWriterFactory tupleWriterFactory;
+    private ITreeIndexTupleWriterFactory tupleWriterFactory;
 
-    public NSMLeafFrameFactory(IBTreeTupleWriterFactory tupleWriterFactory) {
+    public BTreeFieldPrefixNSMLeafFrameFactory(ITreeIndexTupleWriterFactory tupleWriterFactory) {
         this.tupleWriterFactory = tupleWriterFactory;
     }
 
     @Override
-    public IBTreeLeafFrame getFrame() {
-        return new NSMLeafFrame(tupleWriterFactory.createTupleWriter());
+    public IBTreeLeafFrame createFrame() {
+        return new BTreeFieldPrefixNSMLeafFrame(tupleWriterFactory.createTupleWriter());
     }
-}
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMInteriorFrame.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrame.java
similarity index 76%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMInteriorFrame.java
rename to hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrame.java
index 90d400d..6025003 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMInteriorFrame.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrame.java
@@ -25,30 +25,31 @@
 import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeException;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleMode;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleNoExactMatchPolicy;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
 import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SlotOffTupleOff;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SpaceStatus;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.frames.FrameOpSpaceStatus;
+import edu.uci.ics.hyracks.storage.am.common.frames.TreeIndexNSMFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.SlotOffTupleOff;
 
-public class NSMInteriorFrame extends NSMFrame implements IBTreeInteriorFrame {
+public class BTreeNSMInteriorFrame extends TreeIndexNSMFrame implements IBTreeInteriorFrame {
 
     private static final int rightLeafOff = smFlagOff + 1;
 
     private static final int childPtrSize = 4;
-
+    
     // private SimpleTupleReference cmpFrameTuple = new SimpleTupleReference();
-    private IBTreeTupleReference cmpFrameTuple;
+    private ITreeIndexTupleReference cmpFrameTuple;
 
-    public NSMInteriorFrame(IBTreeTupleWriter tupleWriter) {
-        super(tupleWriter);
+    public BTreeNSMInteriorFrame(ITreeIndexTupleWriter tupleWriter) {
+        super(tupleWriter, new OrderedSlotManager());
         cmpFrameTuple = tupleWriter.createTupleReference();
 
     }
@@ -64,21 +65,20 @@
     }
 
     @Override
-    public SpaceStatus hasSpaceInsert(ITupleReference tuple, MultiComparator cmp) {
+    public FrameOpSpaceStatus hasSpaceInsert(ITupleReference tuple, MultiComparator cmp) {
         int bytesRequired = tupleWriter.bytesRequired(tuple) + 8; // for the two
         // childpointers
         if (bytesRequired + slotManager.getSlotSize() <= buf.capacity() - buf.getInt(freeSpaceOff)
                 - (buf.getInt(tupleCountOff) * slotManager.getSlotSize()))
-            return SpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE;
+            return FrameOpSpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE;
         else if (bytesRequired + slotManager.getSlotSize() <= buf.getInt(totalFreeSpaceOff))
-            return SpaceStatus.SUFFICIENT_SPACE;
+            return FrameOpSpaceStatus.SUFFICIENT_SPACE;
         else
-            return SpaceStatus.INSUFFICIENT_SPACE;
+            return FrameOpSpaceStatus.INSUFFICIENT_SPACE;
     }
 
-    @Override
-    public void insert(ITupleReference tuple, MultiComparator cmp) throws Exception {
-        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+    public int findTupleIndex(ITupleReference tuple, MultiComparator cmp) throws Exception {
+    	frameTuple.setFieldCount(cmp.getKeyFieldCount());
         int tupleIndex = slotManager.findTupleIndex(tuple, frameTuple, cmp, FindTupleMode.FTM_INCLUSIVE,
                 FindTupleNoExactMatchPolicy.FTP_HIGHER_KEY);
         int slotOff = slotManager.getSlotOff(tupleIndex);
@@ -87,46 +87,49 @@
         if (tupleIndex < 0)
             isDuplicate = false; // greater than all existing keys
         else {
-            frameTuple.resetByOffset(buf, slotManager.getTupleOff(slotOff));
+            frameTuple.resetByTupleOffset(buf, slotManager.getTupleOff(slotOff));
             if (cmp.compare(tuple, frameTuple) != 0)
                 isDuplicate = false;
         }
-
         if (isDuplicate) {
             throw new BTreeException("Trying to insert duplicate value into interior node.");
-        } else {
-            slotOff = slotManager.insertSlot(tupleIndex, buf.getInt(freeSpaceOff));
-
-            int freeSpace = buf.getInt(freeSpaceOff);
-            int bytesWritten = tupleWriter.writeTupleFields(tuple, 0, cmp.getKeyFieldCount(), buf, freeSpace);
-            System.arraycopy(tuple.getFieldData(cmp.getKeyFieldCount() - 1), getLeftChildPageOff(tuple, cmp), buf
-                    .array(), freeSpace + bytesWritten, childPtrSize);
-            int tupleSize = bytesWritten + childPtrSize;
-
-            buf.putInt(tupleCountOff, buf.getInt(tupleCountOff) + 1);
-            buf.putInt(freeSpaceOff, buf.getInt(freeSpaceOff) + tupleSize);
-            buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) - tupleSize - slotManager.getSlotSize());
-
-            // did insert into the rightmost slot?
-            if (slotOff == slotManager.getSlotEndOff()) {
-                System.arraycopy(tuple.getFieldData(cmp.getKeyFieldCount() - 1), getLeftChildPageOff(tuple, cmp)
-                        + childPtrSize, buf.array(), rightLeafOff, childPtrSize);
-            } else {
-                // if slotOff has a right (slot-)neighbor then update its child
-                // pointer
-                // the only time when this is NOT the case, is when this is the
-                // first tuple
-                // (or when the splitkey goes into the rightmost slot but that
-                // case was handled in the if above)
-                if (buf.getInt(tupleCountOff) > 1) {
-                    int rightNeighborOff = slotOff - slotManager.getSlotSize();
-                    frameTuple.resetByOffset(buf, slotManager.getTupleOff(rightNeighborOff));
-                    System.arraycopy(tuple.getFieldData(0), getLeftChildPageOff(tuple, cmp) + childPtrSize,
-                            buf.array(), getLeftChildPageOff(frameTuple, cmp), childPtrSize);
-                }
-            }
         }
+        return tupleIndex;
     }
+    
+    @Override
+    public void insert(ITupleReference tuple, MultiComparator cmp, int tupleIndex) throws Exception {
+    	int slotOff = slotManager.insertSlot(tupleIndex, buf.getInt(freeSpaceOff));
+    	int freeSpace = buf.getInt(freeSpaceOff);
+    	int bytesWritten = tupleWriter.writeTupleFields(tuple, 0, cmp.getKeyFieldCount(), buf, freeSpace);
+    	System.arraycopy(tuple.getFieldData(cmp.getKeyFieldCount() - 1), getLeftChildPageOff(tuple, cmp), buf
+    			.array(), freeSpace + bytesWritten, childPtrSize);
+    	int tupleSize = bytesWritten + childPtrSize;
+
+    	buf.putInt(tupleCountOff, buf.getInt(tupleCountOff) + 1);
+    	buf.putInt(freeSpaceOff, buf.getInt(freeSpaceOff) + tupleSize);
+    	buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) - tupleSize - slotManager.getSlotSize());
+
+    	// did insert into the rightmost slot?
+    	if (slotOff == slotManager.getSlotEndOff()) {
+    		System.arraycopy(tuple.getFieldData(cmp.getKeyFieldCount() - 1), getLeftChildPageOff(tuple, cmp)
+    				+ childPtrSize, buf.array(), rightLeafOff, childPtrSize);
+    	} else {
+    		// if slotOff has a right (slot-)neighbor then update its child
+    		// pointer
+    		// the only time when this is NOT the case, is when this is the
+    		// first tuple
+    		// (or when the splitkey goes into the rightmost slot but that
+    		// case was handled in the if above)
+    		if (buf.getInt(tupleCountOff) > 1) {
+    			int rightNeighborOff = slotOff - slotManager.getSlotSize();
+    			frameTuple.resetByTupleOffset(buf, slotManager.getTupleOff(rightNeighborOff));
+    			System.arraycopy(tuple.getFieldData(0), getLeftChildPageOff(tuple, cmp) + childPtrSize,
+    					buf.array(), getLeftChildPageOff(frameTuple, cmp), childPtrSize);
+    		}
+    	}
+    }
+
 
     @Override
     public void insertSorted(ITupleReference tuple, MultiComparator cmp) throws HyracksDataException {
@@ -144,26 +147,17 @@
     }
 
     @Override
-    public int split(IBTreeFrame rightFrame, ITupleReference tuple, MultiComparator cmp, SplitKey splitKey)
+    public int split(ITreeIndexFrame rightFrame, ITupleReference tuple, MultiComparator cmp, ISplitKey splitKey)
             throws Exception {
         // before doing anything check if key already exists
         frameTuple.setFieldCount(cmp.getKeyFieldCount());
-        int tupleIndex = slotManager.findTupleIndex(tuple, frameTuple, cmp, FindTupleMode.FTM_EXACT,
-                FindTupleNoExactMatchPolicy.FTP_HIGHER_KEY);
-        int slotOff = slotManager.getSlotOff(tupleIndex);
-        if (tupleIndex >= 0) {
-            frameTuple.resetByOffset(buf, slotManager.getTupleOff(slotOff));
-            if (cmp.compare(tuple, frameTuple) == 0) {
-                throw new BTreeException("Inserting duplicate key in interior node during split");
-            }
-        }
-
+        
         ByteBuffer right = rightFrame.getBuffer();
         int tupleCount = buf.getInt(tupleCountOff);
 
         int tuplesToLeft = (tupleCount / 2) + (tupleCount % 2);
-        IBTreeFrame targetFrame = null;
-        frameTuple.resetByOffset(buf, getTupleOffset(tuplesToLeft - 1));
+        ITreeIndexFrame targetFrame = null;
+        frameTuple.resetByTupleOffset(buf, getTupleOffset(tuplesToLeft - 1));
         if (cmp.compare(tuple, frameTuple) <= 0) {
             targetFrame = this;
         } else {
@@ -189,18 +183,18 @@
         // copy data to be inserted, we need this because creating the splitkey
         // will overwrite the data param (data points to same memory as
         // splitKey.getData())
-        SplitKey savedSplitKey = splitKey.duplicate(tupleWriter.createTupleReference());
+        ISplitKey savedSplitKey = splitKey.duplicate(tupleWriter.createTupleReference());
 
         // set split key to be highest value in left page
         int tupleOff = slotManager.getTupleOff(slotManager.getSlotEndOff());
-        frameTuple.resetByOffset(buf, tupleOff);
+        frameTuple.resetByTupleOffset(buf, tupleOff);
         int splitKeySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
         splitKey.initData(splitKeySize);
         tupleWriter.writeTupleFields(frameTuple, 0, cmp.getKeyFieldCount(), splitKey.getBuffer(), 0);
-        splitKey.getTuple().resetByOffset(splitKey.getBuffer(), 0);
+        splitKey.getTuple().resetByTupleOffset(splitKey.getBuffer(), 0);
 
         int deleteTupleOff = slotManager.getTupleOff(slotManager.getSlotEndOff());
-        frameTuple.resetByOffset(buf, deleteTupleOff);
+        frameTuple.resetByTupleOffset(buf, deleteTupleOff);
         buf.putInt(rightLeafOff, buf.getInt(getLeftChildPageOff(frameTuple, cmp)));
         buf.putInt(tupleCountOff, tuplesToLeft - 1);
 
@@ -209,13 +203,14 @@
         compact(cmp);
 
         // insert key
-        targetFrame.insert(savedSplitKey.getTuple(), cmp);
-
+        int targetTupleIndex = targetFrame.findTupleIndex(savedSplitKey.getTuple(), cmp);
+        targetFrame.insert(savedSplitKey.getTuple(), cmp, targetTupleIndex);
+        
         return 0;
     }
 
     @Override
-    public void compact(MultiComparator cmp) {
+    public boolean compact(MultiComparator cmp) {
         resetSpaceParams();
 
         frameTuple.setFieldCount(cmp.getKeyFieldCount());
@@ -234,7 +229,7 @@
 
         for (int i = 0; i < sortedTupleOffs.size(); i++) {
             int tupleOff = sortedTupleOffs.get(i).tupleOff;
-            frameTuple.resetByOffset(buf, tupleOff);
+            frameTuple.resetByTupleOffset(buf, tupleOff);
 
             int tupleEndOff = frameTuple.getFieldStart(frameTuple.getFieldCount() - 1)
                     + frameTuple.getFieldLength(frameTuple.getFieldCount() - 1);
@@ -247,6 +242,8 @@
 
         buf.putInt(freeSpaceOff, freeSpace);
         buf.putInt(totalFreeSpaceOff, buf.capacity() - freeSpace - tupleCount * slotManager.getSlotSize());
+        
+        return false;
     }
 
     @Override
@@ -294,14 +291,14 @@
             return buf.getInt(rightLeafOff);
         } else {
             int origTupleOff = slotManager.getTupleOff(slotOff);
-            cmpFrameTuple.resetByOffset(buf, origTupleOff);
+            cmpFrameTuple.resetByTupleOffset(buf, origTupleOff);
             int cmpTupleOff = origTupleOff;
             if (pred.isForward()) {
                 int maxSlotOff = buf.capacity();
                 slotOff += slotManager.getSlotSize();
                 while (slotOff < maxSlotOff) {
                     cmpTupleOff = slotManager.getTupleOff(slotOff);
-                    frameTuple.resetByOffset(buf, cmpTupleOff);
+                    frameTuple.resetByTupleOffset(buf, cmpTupleOff);
                     if (targetCmp.compare(cmpFrameTuple, frameTuple) != 0)
                         break;
                     slotOff += slotManager.getSlotSize();
@@ -312,15 +309,15 @@
                 slotOff -= slotManager.getSlotSize();
                 while (slotOff > minSlotOff) {
                     cmpTupleOff = slotManager.getTupleOff(slotOff);
-                    frameTuple.resetByOffset(buf, cmpTupleOff);
+                    frameTuple.resetByTupleOffset(buf, cmpTupleOff);
                     if (targetCmp.compare(cmpFrameTuple, frameTuple) != 0)
                         break;
                     slotOff -= slotManager.getSlotSize();
                 }
                 slotOff += slotManager.getSlotSize();
             }
-
-            frameTuple.resetByOffset(buf, slotManager.getTupleOff(slotOff));
+            
+            frameTuple.resetByTupleOffset(buf, slotManager.getTupleOff(slotOff));
             int childPageOff = getLeftChildPageOff(frameTuple, srcCmp);
             return buf.getInt(childPageOff);
         }
@@ -337,14 +334,14 @@
 
         if (tupleIndex < 0) {
             tupleOff = slotManager.getTupleOff(slotManager.getSlotEndOff());
-            frameTuple.resetByOffset(buf, tupleOff);
+            frameTuple.resetByTupleOffset(buf, tupleOff);
             keySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
 
             // copy new rightmost pointer
             System.arraycopy(buf.array(), tupleOff + keySize, buf.array(), rightLeafOff, childPtrSize);
         } else {
             tupleOff = slotManager.getTupleOff(slotOff);
-            frameTuple.resetByOffset(buf, tupleOff);
+            frameTuple.resetByTupleOffset(buf, tupleOff);
             keySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
             // perform deletion (we just do a memcpy to overwrite the slot)
             int slotStartOff = slotManager.getSlotEndOff();
@@ -368,7 +365,7 @@
     public int getLeftmostChildPageId(MultiComparator cmp) {
         int tupleOff = slotManager.getTupleOff(slotManager.getSlotStartOff());
         frameTuple.setFieldCount(cmp.getKeyFieldCount());
-        frameTuple.resetByOffset(buf, tupleOff);
+        frameTuple.resetByTupleOffset(buf, tupleOff);
         int childPageOff = getLeftChildPageOff(frameTuple, cmp);
         return buf.getInt(childPageOff);
     }
@@ -390,7 +387,7 @@
         int tupleCount = buf.getInt(tupleCountOff);
         for (int i = 0; i < tupleCount; i++) {
             int tupleOff = slotManager.getTupleOff(slotManager.getSlotOff(i));
-            frameTuple.resetByOffset(buf, tupleOff);
+            frameTuple.resetByTupleOffset(buf, tupleOff);
             int intVal = getInt(buf.array(), frameTuple.getFieldStart(frameTuple.getFieldCount() - 1)
                     + frameTuple.getFieldLength(frameTuple.getFieldCount() - 1));
             ret.add(intVal);
@@ -408,7 +405,7 @@
         int slotOff = slotManager.getSlotEndOff();
         int tupleOff = slotManager.getTupleOff(slotOff);
         frameTuple.setFieldCount(cmp.getKeyFieldCount());
-        frameTuple.resetByOffset(buf, tupleOff);
+        frameTuple.resetByTupleOffset(buf, tupleOff);
         int keySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
         System.arraycopy(buf.array(), tupleOff + keySize, buf.array(), rightLeafOff, childPtrSize);
 
@@ -447,4 +444,9 @@
         strBuilder.append("\n");
         return strBuilder.toString();
     }
+    
+    @Override
+	public int getPageHeaderSize() {
+		return rightLeafOff;
+	}
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMInteriorFrameFactory.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrameFactory.java
similarity index 64%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMInteriorFrameFactory.java
rename to hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrameFactory.java
index 86fa94f..6b30ee0 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMInteriorFrameFactory.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMInteriorFrameFactory.java
@@ -16,20 +16,20 @@
 package edu.uci.ics.hyracks.storage.am.btree.frames;
 
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriterFactory;
 
-public class NSMInteriorFrameFactory implements IBTreeInteriorFrameFactory {
+public class BTreeNSMInteriorFrameFactory implements ITreeIndexFrameFactory {
 
     private static final long serialVersionUID = 1L;
-    private IBTreeTupleWriterFactory tupleWriterFactory;
+    private ITreeIndexTupleWriterFactory tupleWriterFactory;
 
-    public NSMInteriorFrameFactory(IBTreeTupleWriterFactory tupleWriterFactory) {
+    public BTreeNSMInteriorFrameFactory(ITreeIndexTupleWriterFactory tupleWriterFactory) {
         this.tupleWriterFactory = tupleWriterFactory;
     }
 
     @Override
-    public IBTreeInteriorFrame getFrame() {
-        return new NSMInteriorFrame(tupleWriterFactory.createTupleWriter());
+    public IBTreeInteriorFrame createFrame() {
+        return new BTreeNSMInteriorFrame(tupleWriterFactory.createTupleWriter());
     }
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMLeafFrame.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMLeafFrame.java
similarity index 69%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMLeafFrame.java
rename to hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMLeafFrame.java
index fd8f826..85fbec9 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMLeafFrame.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMLeafFrame.java
@@ -19,22 +19,23 @@
 
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeException;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleMode;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleNoExactMatchPolicy;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.frames.TreeIndexNSMFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
-public class NSMLeafFrame extends NSMFrame implements IBTreeLeafFrame {
+public class BTreeNSMLeafFrame extends TreeIndexNSMFrame implements IBTreeLeafFrame {
     protected static final int prevLeafOff = smFlagOff + 1;
     protected static final int nextLeafOff = prevLeafOff + 4;
 
-    public NSMLeafFrame(IBTreeTupleWriter tupleWriter) {
-        super(tupleWriter);
+    public BTreeNSMLeafFrame(ITreeIndexTupleWriter tupleWriter) {
+        super(tupleWriter, new OrderedSlotManager());
     }
 
     @Override
@@ -65,8 +66,8 @@
     }
 
     @Override
-    public void insert(ITupleReference tuple, MultiComparator cmp) throws Exception {
-        frameTuple.setFieldCount(cmp.getFieldCount());
+    public int findTupleIndex(ITupleReference tuple, MultiComparator cmp) throws Exception {
+    	frameTuple.setFieldCount(cmp.getFieldCount());
         int tupleIndex = slotManager.findTupleIndex(tuple, frameTuple, cmp, FindTupleMode.FTM_INCLUSIVE,
                 FindTupleNoExactMatchPolicy.FTP_HIGHER_KEY);
         int slotOff = slotManager.getSlotOff(tupleIndex);
@@ -75,23 +76,25 @@
         if (tupleIndex < 0)
             isDuplicate = false; // greater than all existing keys
         else {
-            frameTuple.resetByOffset(buf, slotManager.getTupleOff(slotOff));
+            frameTuple.resetByTupleOffset(buf, slotManager.getTupleOff(slotOff));
             if (cmp.compare(tuple, frameTuple) != 0)
                 isDuplicate = false;
         }
-
         if (isDuplicate) {
             throw new BTreeException("Trying to insert duplicate value into leaf of unique index");
-        } else {
-            slotOff = slotManager.insertSlot(tupleIndex, buf.getInt(freeSpaceOff));
-
-            int freeSpace = buf.getInt(freeSpaceOff);
-            int bytesWritten = tupleWriter.writeTuple(tuple, buf, freeSpace);
-
-            buf.putInt(tupleCountOff, buf.getInt(tupleCountOff) + 1);
-            buf.putInt(freeSpaceOff, buf.getInt(freeSpaceOff) + bytesWritten);
-            buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) - bytesWritten - slotManager.getSlotSize());
         }
+        
+        return tupleIndex;
+    }
+    
+    @Override
+    public void insert(ITupleReference tuple, MultiComparator cmp, int tupleIndex) throws Exception {    	
+    	slotManager.insertSlot(tupleIndex, buf.getInt(freeSpaceOff));
+    	int freeSpace = buf.getInt(freeSpaceOff);
+    	int bytesWritten = tupleWriter.writeTuple(tuple, buf, freeSpace);
+    	buf.putInt(tupleCountOff, buf.getInt(tupleCountOff) + 1);
+    	buf.putInt(freeSpaceOff, buf.getInt(freeSpaceOff) + bytesWritten);
+    	buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) - bytesWritten - slotManager.getSlotSize());
     }
 
     @Override
@@ -105,29 +108,19 @@
     }
 
     @Override
-    public int split(IBTreeFrame rightFrame, ITupleReference tuple, MultiComparator cmp, SplitKey splitKey)
+    public int split(ITreeIndexFrame rightFrame, ITupleReference tuple, MultiComparator cmp, ISplitKey splitKey)
             throws Exception {
 
         frameTuple.setFieldCount(cmp.getFieldCount());
-
-        // before doing anything check if key already exists
-        int tupleIndex = slotManager.findTupleIndex(tuple, frameTuple, cmp, FindTupleMode.FTM_EXACT,
-                FindTupleNoExactMatchPolicy.FTP_HIGHER_KEY);
-        if (tupleIndex >= 0) {
-            frameTuple.resetByTupleIndex(this, tupleIndex);
-            if (cmp.compare(tuple, frameTuple) == 0) {
-                throw new BTreeException("Inserting duplicate key into unique index");
-            }
-        }
-
+        
         ByteBuffer right = rightFrame.getBuffer();
         int tupleCount = getTupleCount();
 
         int tuplesToLeft;
         int mid = tupleCount / 2;
-        IBTreeFrame targetFrame = null;
+        ITreeIndexFrame targetFrame = null;
         int tupleOff = slotManager.getTupleOff(slotManager.getSlotEndOff() + slotManager.getSlotSize() * mid);
-        frameTuple.resetByOffset(buf, tupleOff);
+        frameTuple.resetByTupleOffset(buf, tupleOff);
         if (cmp.compare(tuple, frameTuple) >= 0) {
             tuplesToLeft = mid + (tupleCount % 2);
             targetFrame = rightFrame;
@@ -156,17 +149,18 @@
         compact(cmp);
 
         // insert last key
-        targetFrame.insert(tuple, cmp);
+        int targetTupleIndex = targetFrame.findTupleIndex(tuple, cmp);
+        targetFrame.insert(tuple, cmp, targetTupleIndex);
 
         // set split key to be highest value in left page
         tupleOff = slotManager.getTupleOff(slotManager.getSlotEndOff());
-        frameTuple.resetByOffset(buf, tupleOff);
+        frameTuple.resetByTupleOffset(buf, tupleOff);
 
         int splitKeySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
         splitKey.initData(splitKeySize);
         tupleWriter.writeTupleFields(frameTuple, 0, cmp.getKeyFieldCount(), splitKey.getBuffer(), 0);
-        splitKey.getTuple().resetByOffset(splitKey.getBuffer(), 0);
-
+        splitKey.getTuple().resetByTupleOffset(splitKey.getBuffer(), 0);
+        
         return 0;
     }
 
@@ -177,13 +171,18 @@
     }
 
     @Override
-    public IBTreeTupleReference createTupleReference() {
+    public ITreeIndexTupleReference createTupleReference() {
         return tupleWriter.createTupleReference();
     }
 
     @Override
-    public int findTupleIndex(ITupleReference searchKey, IBTreeTupleReference pageTuple, MultiComparator cmp,
+    public int findTupleIndex(ITupleReference searchKey, ITreeIndexTupleReference pageTuple, MultiComparator cmp,
             FindTupleMode ftm, FindTupleNoExactMatchPolicy ftp) {
         return slotManager.findTupleIndex(searchKey, pageTuple, cmp, ftm, ftp);
     }
+
+	@Override
+	public int getPageHeaderSize() {
+		return nextLeafOff;
+	}
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMLeafFrameFactory.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMLeafFrameFactory.java
similarity index 64%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMLeafFrameFactory.java
rename to hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMLeafFrameFactory.java
index 202f31a..d59b391 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMLeafFrameFactory.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/BTreeNSMLeafFrameFactory.java
@@ -16,20 +16,20 @@
 package edu.uci.ics.hyracks.storage.am.btree.frames;
 
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriterFactory;
 
-public class NSMLeafFrameFactory implements IBTreeLeafFrameFactory {
+public class BTreeNSMLeafFrameFactory implements ITreeIndexFrameFactory {
 
     private static final long serialVersionUID = 1L;
-    private IBTreeTupleWriterFactory tupleWriterFactory;
+    private ITreeIndexTupleWriterFactory tupleWriterFactory;
 
-    public NSMLeafFrameFactory(IBTreeTupleWriterFactory tupleWriterFactory) {
+    public BTreeNSMLeafFrameFactory(ITreeIndexTupleWriterFactory tupleWriterFactory) {
         this.tupleWriterFactory = tupleWriterFactory;
     }
 
     @Override
-    public IBTreeLeafFrame getFrame() {
-        return new NSMLeafFrame(tupleWriterFactory.createTupleWriter());
+    public IBTreeLeafFrame createFrame() {
+        return new BTreeNSMLeafFrame(tupleWriterFactory.createTupleWriter());
     }
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/FieldPrefixNSMLeafFrameFactory.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/FieldPrefixNSMLeafFrameFactory.java
deleted file mode 100644
index a3084ab..0000000
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/FieldPrefixNSMLeafFrameFactory.java
+++ /dev/null
@@ -1,35 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.btree.frames;
-
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriterFactory;
-
-public class FieldPrefixNSMLeafFrameFactory implements IBTreeLeafFrameFactory {
-
-    private static final long serialVersionUID = 1L;
-    private IBTreeTupleWriterFactory tupleWriterFactory;
-
-    public FieldPrefixNSMLeafFrameFactory(IBTreeTupleWriterFactory tupleWriterFactory) {
-        this.tupleWriterFactory = tupleWriterFactory;
-    }
-
-    @Override
-    public IBTreeLeafFrame getFrame() {
-        return new FieldPrefixNSMLeafFrame(tupleWriterFactory.createTupleWriter());
-    }
-}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/OrderedSlotManager.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/OrderedSlotManager.java
similarity index 66%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/OrderedSlotManager.java
rename to hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/OrderedSlotManager.java
index 258161b..89a70e0 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/OrderedSlotManager.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/OrderedSlotManager.java
@@ -13,20 +13,24 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.btree.frames;
+
+import java.io.ByteArrayInputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.ISlotManager;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.frames.AbstractSlotManager;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
-public class OrderedSlotManager implements ISlotManager {
-
-    private static final int slotSize = 4;
-    private IBTreeFrame frame;
-
-    @Override
-    public int findTupleIndex(ITupleReference searchKey, IBTreeTupleReference frameTuple, MultiComparator multiCmp,
+public class OrderedSlotManager extends AbstractSlotManager {
+    
+	@Override
+    public int findTupleIndex(ITupleReference searchKey, ITreeIndexTupleReference frameTuple, MultiComparator multiCmp,
             FindTupleMode mode, FindTupleNoExactMatchPolicy matchPolicy) {
         if (frame.getTupleCount() <= 0)
             return -1;
@@ -34,12 +38,12 @@
         int mid;
         int begin = 0;
         int end = frame.getTupleCount() - 1;
-
+        
         while (begin <= end) {
             mid = (begin + end) / 2;
-            frameTuple.resetByTupleIndex(frame, mid);
-
-            int cmp = multiCmp.compare(searchKey, frameTuple);
+            frameTuple.resetByTupleIndex(frame, mid);            
+            
+            int cmp = multiCmp.compare(searchKey, frameTuple);            
             if (cmp < 0) {
                 end = mid - 1;
             } else if (cmp > 0) {
@@ -77,32 +81,7 @@
                 return -1;
         }
     }
-
-    @Override
-    public int getTupleOff(int offset) {
-        return frame.getBuffer().getInt(offset);
-    }
-
-    @Override
-    public void setSlot(int offset, int value) {
-        frame.getBuffer().putInt(offset, value);
-    }
-
-    @Override
-    public int getSlotEndOff() {
-        return frame.getBuffer().capacity() - (frame.getTupleCount() * slotSize);
-    }
-
-    @Override
-    public int getSlotStartOff() {
-        return frame.getBuffer().capacity() - slotSize;
-    }
-
-    @Override
-    public int getSlotSize() {
-        return slotSize;
-    }
-
+    
     @Override
     public int insertSlot(int tupleIndex, int tupleOff) {
         int slotOff = getSlotOff(tupleIndex);
@@ -119,14 +98,4 @@
             return slotOff;
         }
     }
-
-    @Override
-    public void setFrame(IBTreeFrame frame) {
-        this.frame = frame;
-    }
-
-    @Override
-    public int getSlotOff(int tupleIndex) {
-        return getSlotStartOff() - tupleIndex * slotSize;
-    }
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java
index 7a8ee73..2831ff6 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTree.java
@@ -22,35 +22,47 @@
 import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeCursor;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrame;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexBulkLoadContext;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.api.IndexType;
+import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
+import edu.uci.ics.hyracks.storage.am.common.frames.FrameOpSpaceStatus;
+import edu.uci.ics.hyracks.storage.am.common.impls.TreeDiskOrderScanCursor;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOpContext;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
 
-public class BTree {
+public class BTree implements ITreeIndex {
+
+    public static final float DEFAULT_FILL_FACTOR = 0.7f;
 
     private final static int RESTART_OP = Integer.MIN_VALUE;
     private final static int MAX_RESTARTS = 10;
 
-    private final int metaDataPage = 0; // page containing meta data, e.g.,
-    // maxPage
-    private final int rootPage = 1; // the root page never changes
+    // the root page never changes
+    private final int rootPage = 1;
+
+    private final IFreePageManager freePageManager;
 
     private boolean created = false;
     private boolean loaded = false;
 
     private final IBufferCache bufferCache;
     private int fileId;
-    private final IBTreeInteriorFrameFactory interiorFrameFactory;
-    private final IBTreeLeafFrameFactory leafFrameFactory;
+    private final ITreeIndexFrameFactory interiorFrameFactory;
+    private final ITreeIndexFrameFactory leafFrameFactory;
     private final MultiComparator cmp;
     private final ReadWriteLock treeLatch;
     private final RangePredicate diskOrderScanPredicate;
@@ -90,17 +102,19 @@
         return strBuilder.toString();
     }
 
-    public BTree(IBufferCache bufferCache, IBTreeInteriorFrameFactory interiorFrameFactory,
-            IBTreeLeafFrameFactory leafFrameFactory, MultiComparator cmp) {
+    public BTree(IBufferCache bufferCache, IFreePageManager freePageManager,
+            ITreeIndexFrameFactory interiorFrameFactory, ITreeIndexFrameFactory leafFrameFactory, MultiComparator cmp) {
         this.bufferCache = bufferCache;
         this.interiorFrameFactory = interiorFrameFactory;
         this.leafFrameFactory = leafFrameFactory;
         this.cmp = cmp;
+        this.freePageManager = freePageManager;
         this.treeLatch = new ReentrantReadWriteLock(true);
         this.diskOrderScanPredicate = new RangePredicate(true, null, null, true, true, cmp, cmp);
     }
 
-    public void create(int fileId, IBTreeLeafFrame leafFrame, IBTreeMetaDataFrame metaFrame) throws Exception {
+    @Override
+    public void create(int fileId, ITreeIndexFrame leafFrame, ITreeIndexMetaDataFrame metaFrame) throws Exception {
 
         if (created)
             return;
@@ -112,22 +126,7 @@
             if (created)
                 return;
 
-            // initialize meta data page
-            ICachedPage metaNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, metaDataPage), false);
-            pins++;
-
-            metaNode.acquireWriteLatch();
-            writeLatchesAcquired++;
-            try {
-                metaFrame.setPage(metaNode);
-                metaFrame.initBuffer((byte) -1);
-                metaFrame.setMaxPage(rootPage);
-            } finally {
-                metaNode.releaseWriteLatch();
-                writeLatchesReleased++;
-                bufferCache.unpin(metaNode);
-                unpins++;
-            }
+            freePageManager.init(metaFrame, rootPage);
 
             // initialize root page
             ICachedPage rootNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, rootPage), true);
@@ -160,158 +159,16 @@
         fileId = -1;
     }
 
-    private int getFreePage(IBTreeMetaDataFrame metaFrame) throws HyracksDataException {
-        ICachedPage metaNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, metaDataPage), false);
-        pins++;
-
-        metaNode.acquireWriteLatch();
-        writeLatchesAcquired++;
-
-        int freePage = -1;
-        try {
-            metaFrame.setPage(metaNode);
-            freePage = metaFrame.getFreePage();
-            if (freePage < 0) { // no free page entry on this page
-                int nextPage = metaFrame.getNextPage();
-                if (nextPage > 0) { // sibling may have free pages
-                    ICachedPage nextNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, nextPage), false);
-                    pins++;
-
-                    nextNode.acquireWriteLatch();
-                    writeLatchesAcquired++;
-                    // we copy over the free space entries of nextpage into the
-                    // first meta page (metaDataPage)
-                    // we need to link the first page properly to the next page
-                    // of nextpage
-                    try {
-                        // remember entries that remain unchanged
-                        int maxPage = metaFrame.getMaxPage();
-
-                        // copy entire page (including sibling pointer, free
-                        // page entries, and all other info)
-                        // after this copy nextPage is considered a free page
-                        System.arraycopy(nextNode.getBuffer().array(), 0, metaNode.getBuffer().array(), 0, nextNode
-                                .getBuffer().capacity());
-
-                        // reset unchanged entry
-                        metaFrame.setMaxPage(maxPage);
-
-                        freePage = metaFrame.getFreePage();
-                        // sibling also has no free pages, this "should" not
-                        // happen, but we deal with it anyway just to be safe
-                        if (freePage < 0) {
-                            freePage = nextPage;
-                        } else {
-                            metaFrame.addFreePage(nextPage);
-                        }
-                    } finally {
-                        nextNode.releaseWriteLatch();
-                        writeLatchesReleased++;
-                        bufferCache.unpin(nextNode);
-                        unpins++;
-                    }
-                } else {
-                    freePage = metaFrame.getMaxPage();
-                    freePage++;
-                    metaFrame.setMaxPage(freePage);
-                }
-            }
-        } finally {
-            metaNode.releaseWriteLatch();
-            writeLatchesReleased++;
-            bufferCache.unpin(metaNode);
-            unpins++;
-        }
-
-        return freePage;
-    }
-
     private void addFreePages(BTreeOpContext ctx) throws Exception {
         for (int i = 0; i < ctx.freePages.size(); i++) {
-            addFreePage(ctx.metaFrame, ctx.freePages.get(i));
+            // root page is special, don't add it to free pages
+            if (ctx.freePages.get(i) != rootPage) {
+                freePageManager.addFreePage(ctx.metaFrame, ctx.freePages.get(i));
+            }
         }
         ctx.freePages.clear();
     }
 
-    private void addFreePage(IBTreeMetaDataFrame metaFrame, int freePage) throws Exception {
-        // root page is special, don't add it to free pages
-        if (freePage == rootPage)
-            return;
-
-        ICachedPage metaNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, metaDataPage), false);
-        pins++;
-
-        metaNode.acquireWriteLatch();
-        writeLatchesAcquired++;
-
-        metaFrame.setPage(metaNode);
-
-        try {
-            if (metaFrame.hasSpace()) {
-                metaFrame.addFreePage(freePage);
-            } else {
-                // allocate a new page in the chain of meta pages
-                int newPage = metaFrame.getFreePage();
-                if (newPage < 0) {
-                    throw new Exception("Inconsistent Meta Page State. It has no space, but it also has no entries.");
-                }
-
-                ICachedPage newNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, newPage), false);
-                pins++;
-
-                newNode.acquireWriteLatch();
-                writeLatchesAcquired++;
-
-                try {
-                    int metaMaxPage = metaFrame.getMaxPage();
-
-                    // copy metaDataPage to newNode
-                    System.arraycopy(metaNode.getBuffer().array(), 0, newNode.getBuffer().array(), 0, metaNode
-                            .getBuffer().capacity());
-
-                    metaFrame.initBuffer(-1);
-                    metaFrame.setNextPage(newPage);
-                    metaFrame.setMaxPage(metaMaxPage);
-                    metaFrame.addFreePage(freePage);
-                } finally {
-                    newNode.releaseWriteLatch();
-                    writeLatchesReleased++;
-
-                    bufferCache.unpin(newNode);
-                    unpins++;
-                }
-            }
-        } catch (Exception e) {
-            e.printStackTrace();
-        } finally {
-            metaNode.releaseWriteLatch();
-            writeLatchesReleased++;
-
-            bufferCache.unpin(metaNode);
-            unpins++;
-        }
-    }
-
-    public int getMaxPage(IBTreeMetaDataFrame metaFrame) throws HyracksDataException {
-        ICachedPage metaNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, metaDataPage), false);
-        pins++;
-
-        metaNode.acquireWriteLatch();
-        writeLatchesAcquired++;
-        int maxPage = -1;
-        try {
-            metaFrame.setPage(metaNode);
-            maxPage = metaFrame.getMaxPage();
-        } finally {
-            metaNode.releaseWriteLatch();
-            writeLatchesReleased++;
-            bufferCache.unpin(metaNode);
-            unpins++;
-        }
-
-        return maxPage;
-    }
-
     public void printTree(IBTreeLeafFrame leafFrame, IBTreeInteriorFrame interiorFrame, ISerializerDeserializer[] fields)
             throws Exception {
         printTree(rootPage, null, false, leafFrame, interiorFrame, fields);
@@ -352,7 +209,7 @@
 
             System.out.format(keyString);
             if (!interiorFrame.isLeaf()) {
-                ArrayList<Integer> children = ((NSMInteriorFrame) (interiorFrame)).getChildren(cmp);
+                ArrayList<Integer> children = ((BTreeNSMInteriorFrame) (interiorFrame)).getChildren(cmp);
 
                 for (int i = 0; i < children.size(); i++) {
                     printTree(children.get(i), node, i == children.size() - 1, leafFrame, interiorFrame, fields);
@@ -374,27 +231,15 @@
         }
     }
 
-    public void diskOrderScan(DiskOrderScanCursor cursor, IBTreeLeafFrame leafFrame, IBTreeMetaDataFrame metaFrame)
-            throws HyracksDataException {
+    @Override
+    public void diskOrderScan(ITreeIndexCursor icursor, ITreeIndexFrame leafFrame, ITreeIndexMetaDataFrame metaFrame,
+            IndexOpContext ictx) throws HyracksDataException {
+        TreeDiskOrderScanCursor cursor = (TreeDiskOrderScanCursor) icursor;
+        BTreeOpContext ctx = (BTreeOpContext) ictx;
+        ctx.reset();
+
         int currentPageId = rootPage + 1;
-        int maxPageId = -1;
-
-        ICachedPage metaNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, metaDataPage), false);
-        pins++;
-
-        metaNode.acquireReadLatch();
-        readLatchesAcquired++;
-
-        try {
-            metaFrame.setPage(metaNode);
-            maxPageId = metaFrame.getMaxPage();
-        } finally {
-            metaNode.releaseReadLatch();
-            readLatchesAcquired++;
-
-            bufferCache.unpin(metaNode);
-            unpins++;
-        }
+        int maxPageId = freePageManager.getMaxPage(metaFrame);
 
         ICachedPage page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, currentPageId), false);
         page.acquireReadLatch();
@@ -402,10 +247,11 @@
         cursor.setFileId(fileId);
         cursor.setCurrentPageId(currentPageId);
         cursor.setMaxPageId(maxPageId);
-        cursor.open(page, diskOrderScanPredicate);
+        ctx.cursorInitialState.setPage(page);
+        cursor.open(ctx.cursorInitialState, diskOrderScanPredicate);
     }
 
-    public void search(IBTreeCursor cursor, RangePredicate pred, BTreeOpContext ctx) throws Exception {
+    public void search(ITreeIndexCursor cursor, RangePredicate pred, BTreeOpContext ctx) throws Exception {
         ctx.reset();
         ctx.pred = pred;
         ctx.cursor = cursor;
@@ -468,20 +314,21 @@
         currentLevel++;
 
         // make sure the root is always at the same level
-        ICachedPage leftNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, ctx.splitKey.getLeftPage()), false);
+        ICachedPage leftNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, ctx.splitKey.getLeftPage()),
+                false);
         pins++;
         leftNode.acquireWriteLatch(); // TODO: think about whether latching is
         // really required
         writeLatchesAcquired++;
         try {
-            ICachedPage rightNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, ctx.splitKey.getRightPage()),
-                    false);
+            ICachedPage rightNode = bufferCache.pin(
+                    BufferedFileHandle.getDiskPageId(fileId, ctx.splitKey.getRightPage()), false);
             pins++;
             rightNode.acquireWriteLatch(); // TODO: think about whether latching
             // is really required
             writeLatchesAcquired++;
             try {
-                int newLeftId = getFreePage(ctx.metaFrame);
+                int newLeftId = freePageManager.getFreePage(ctx.metaFrame);
                 ICachedPage newLeftNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, newLeftId), true);
                 pins++;
                 newLeftNode.acquireWriteLatch(); // TODO: think about whether
@@ -507,7 +354,8 @@
                     ctx.interiorFrame.setSmFlag(true); // will be cleared later
                     // in unsetSmPages
                     ctx.splitKey.setLeftPage(newLeftId);
-                    ctx.interiorFrame.insert(ctx.splitKey.getTuple(), cmp);
+                    int targetTupleIndex = ctx.interiorFrame.findTupleIndex(ctx.splitKey.getTuple(), cmp);
+                    ctx.interiorFrame.insert(ctx.splitKey.getTuple(), cmp, targetTupleIndex);
                 } finally {
                     newLeftNode.releaseWriteLatch();
                     writeLatchesReleased++;
@@ -528,7 +376,9 @@
         }
     }
 
-    public void insert(ITupleReference tuple, BTreeOpContext ctx) throws Exception {
+    @Override
+    public void insert(ITupleReference tuple, IndexOpContext ictx) throws Exception {
+        BTreeOpContext ctx = (BTreeOpContext) ictx;
         ctx.reset();
         ctx.pred.setLowKeyComparator(cmp);
         ctx.pred.setHighKeyComparator(cmp);
@@ -566,20 +416,24 @@
     private void insertLeaf(ICachedPage node, int pageId, ITupleReference tuple, BTreeOpContext ctx) throws Exception {
         ctx.leafFrame.setPage(node);
         ctx.leafFrame.setPageTupleFieldCount(cmp.getFieldCount());
-        SpaceStatus spaceStatus = ctx.leafFrame.hasSpaceInsert(tuple, cmp);
+
+        int targetTupleIndex = ctx.leafFrame.findTupleIndex(tuple, cmp);
+        FrameOpSpaceStatus spaceStatus = ctx.leafFrame.hasSpaceInsert(tuple, cmp);
         switch (spaceStatus) {
 
             case SUFFICIENT_CONTIGUOUS_SPACE: {
                 // System.out.println("SUFFICIENT_CONTIGUOUS_SPACE");
-                ctx.leafFrame.insert(tuple, cmp);
+                ctx.leafFrame.insert(tuple, cmp, targetTupleIndex);
                 ctx.splitKey.reset();
             }
                 break;
 
             case SUFFICIENT_SPACE: {
                 // System.out.println("SUFFICIENT_SPACE");
-                ctx.leafFrame.compact(cmp);
-                ctx.leafFrame.insert(tuple, cmp);
+                boolean slotsChanged = ctx.leafFrame.compact(cmp);
+                if (slotsChanged)
+                    targetTupleIndex = ctx.leafFrame.findTupleIndex(tuple, cmp);
+                ctx.leafFrame.insert(tuple, cmp, targetTupleIndex);
                 ctx.splitKey.reset();
             }
                 break;
@@ -595,8 +449,8 @@
                 if (reCompressed)
                     spaceStatus = ctx.leafFrame.hasSpaceInsert(tuple, cmp);
 
-                if (spaceStatus == SpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE) {
-                    ctx.leafFrame.insert(tuple, cmp);
+                if (spaceStatus == FrameOpSpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE) {
+                    ctx.leafFrame.insert(tuple, cmp, targetTupleIndex);
                     ctx.splitKey.reset();
 
                     usefulCompression++;
@@ -610,7 +464,8 @@
                     int rightSiblingPageId = ctx.leafFrame.getNextLeaf();
                     ICachedPage rightSibling = null;
                     if (rightSiblingPageId > 0) {
-                        rightSibling = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, rightSiblingPageId), false);
+                        rightSibling = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, rightSiblingPageId),
+                                false);
                         pins++;
                     }
 
@@ -620,13 +475,14 @@
                     treeLatchesAcquired++;
                     try {
 
-                        int rightPageId = getFreePage(ctx.metaFrame);
-                        ICachedPage rightNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, rightPageId), true);
+                        int rightPageId = freePageManager.getFreePage(ctx.metaFrame);
+                        ICachedPage rightNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, rightPageId),
+                                true);
                         pins++;
                         rightNode.acquireWriteLatch();
                         writeLatchesAcquired++;
                         try {
-                            IBTreeLeafFrame rightFrame = leafFrameFactory.getFrame();
+                            IBTreeLeafFrame rightFrame = (IBTreeLeafFrame) leafFrameFactory.createFrame();
                             rightFrame.setPage(rightNode);
                             rightFrame.initBuffer((byte) 0);
                             rightFrame.setPageTupleFieldCount(cmp.getFieldCount());
@@ -704,17 +560,19 @@
             throws Exception {
         ctx.interiorFrame.setPage(node);
         ctx.interiorFrame.setPageTupleFieldCount(cmp.getKeyFieldCount());
-        SpaceStatus spaceStatus = ctx.interiorFrame.hasSpaceInsert(tuple, cmp);
+
+        int targetTupleIndex = ctx.interiorFrame.findTupleIndex(tuple, cmp);
+        FrameOpSpaceStatus spaceStatus = ctx.interiorFrame.hasSpaceInsert(tuple, cmp);
         switch (spaceStatus) {
             case INSUFFICIENT_SPACE: {
                 splitsByLevel[ctx.interiorFrame.getLevel()]++; // debug
-                int rightPageId = getFreePage(ctx.metaFrame);
+                int rightPageId = freePageManager.getFreePage(ctx.metaFrame);
                 ICachedPage rightNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, rightPageId), true);
                 pins++;
                 rightNode.acquireWriteLatch();
                 writeLatchesAcquired++;
                 try {
-                    IBTreeFrame rightFrame = interiorFrameFactory.getFrame();
+                    ITreeIndexFrame rightFrame = interiorFrameFactory.createFrame();
                     rightFrame.setPage(rightNode);
                     rightFrame.initBuffer((byte) ctx.interiorFrame.getLevel());
                     rightFrame.setPageTupleFieldCount(cmp.getKeyFieldCount());
@@ -753,14 +611,16 @@
 
             case SUFFICIENT_CONTIGUOUS_SPACE: {
                 // System.out.println("INSERT INTERIOR: " + pageId);
-                ctx.interiorFrame.insert(tuple, cmp);
+                ctx.interiorFrame.insert(tuple, cmp, targetTupleIndex);
                 ctx.splitKey.reset();
             }
                 break;
 
             case SUFFICIENT_SPACE: {
-                ctx.interiorFrame.compact(cmp);
-                ctx.interiorFrame.insert(tuple, cmp);
+                boolean slotsChanged = ctx.interiorFrame.compact(cmp);
+                if (slotsChanged)
+                    targetTupleIndex = ctx.interiorFrame.findTupleIndex(tuple, cmp);
+                ctx.interiorFrame.insert(tuple, cmp, targetTupleIndex);
                 ctx.splitKey.reset();
             }
                 break;
@@ -768,7 +628,9 @@
         }
     }
 
-    public void delete(ITupleReference tuple, BTreeOpContext ctx) throws Exception {
+    @Override
+    public void delete(ITupleReference tuple, IndexOpContext ictx) throws Exception {
+        BTreeOpContext ctx = (BTreeOpContext) ictx;
         ctx.reset();
         ctx.pred.setLowKeyComparator(cmp);
         ctx.pred.setHighKeyComparator(cmp);
@@ -822,7 +684,7 @@
 
         // will this leaf become empty?
         if (ctx.leafFrame.getTupleCount() == 1) {
-            IBTreeLeafFrame siblingFrame = leafFrameFactory.getFrame();
+            IBTreeLeafFrame siblingFrame = (IBTreeLeafFrame) leafFrameFactory.createFrame();
 
             ICachedPage leftNode = null;
             ICachedPage rightNode = null;
@@ -855,11 +717,9 @@
                         throw e;
                     }
 
-                    ctx.leafFrame.setPageLsn(ctx.leafFrame.getPageLsn() + 1); // TODO:
-                    // tie
-                    // together
-                    // with
-                    // logging
+                    // TODO: tie together with loggins
+                    ctx.leafFrame.setPageLsn(ctx.leafFrame.getPageLsn() + 1);
+                    ctx.leafFrame.setLevel(freePageManager.getFreePageLevelIndicator());
 
                     ctx.smPages.add(pageId);
                     ctx.leafFrame.setSmFlag(true);
@@ -937,6 +797,7 @@
             // together
             // with
             // logging
+            ctx.leafFrame.setLevel(freePageManager.getFreePageLevelIndicator());
             ctx.smPages.add(pageId);
             ctx.interiorFrame.setSmFlag(true);
             ctx.interiorFrame.setRightmostChildPageId(-1); // this node is
@@ -955,8 +816,8 @@
         }
     }
 
-    private final void acquireLatch(ICachedPage node, BTreeOp op, boolean isLeaf) {
-        if (isLeaf && (op.equals(BTreeOp.BTO_INSERT) || op.equals(BTreeOp.BTO_DELETE))) {
+    private final void acquireLatch(ICachedPage node, IndexOp op, boolean isLeaf) {
+        if (isLeaf && (op.equals(IndexOp.INSERT) || op.equals(IndexOp.DELETE))) {
             node.acquireWriteLatch();
             writeLatchesAcquired++;
         } else {
@@ -965,8 +826,8 @@
         }
     }
 
-    private final void releaseLatch(ICachedPage node, BTreeOp op, boolean isLeaf) {
-        if (isLeaf && (op.equals(BTreeOp.BTO_INSERT) || op.equals(BTreeOp.BTO_DELETE))) {
+    private final void releaseLatch(ICachedPage node, IndexOp op, boolean isLeaf) {
+        if (isLeaf && (op.equals(IndexOp.INSERT) || op.equals(IndexOp.DELETE))) {
             node.releaseWriteLatch();
             writeLatchesReleased++;
         } else {
@@ -998,9 +859,13 @@
         pins++;
 
         ctx.interiorFrame.setPage(node);
-        boolean isLeaf = ctx.interiorFrame.isLeaf();
-        acquireLatch(node, ctx.op, isLeaf);
+        // this check performs an unprotected read in the page
+        // the following could happen: TODO fill out
+        boolean unsafeIsLeaf = ctx.interiorFrame.isLeaf();
+        acquireLatch(node, ctx.op, unsafeIsLeaf);
         boolean smFlag = ctx.interiorFrame.getSmFlag();
+        // re-check leafness after latching
+        boolean isLeaf = ctx.interiorFrame.isLeaf();
 
         // remember trail of pageLsns, to unwind recursion in case of an ongoing
         // structure modification
@@ -1053,7 +918,7 @@
 
                         switch (ctx.op) {
 
-                            case BTO_INSERT: {
+                            case INSERT: {
                                 if (ctx.splitKey.getBuffer() != null) {
                                     node = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
                                     pins++;
@@ -1073,7 +938,7 @@
                             }
                                 break;
 
-                            case BTO_DELETE: {
+                            case DELETE: {
                                 if (ctx.splitKey.getBuffer() != null) {
                                     node = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
                                     pins++;
@@ -1093,7 +958,7 @@
                             }
                                 break;
 
-                            case BTO_SEARCH: {
+                            case SEARCH: {
                                 // do nothing
                             }
                                 break;
@@ -1107,7 +972,7 @@
                     ctx.opRestarts++;
                     System.out.println("ONGOING SM ON PAGE " + pageId + " AT LEVEL " + ctx.interiorFrame.getLevel()
                             + ", RESTARTS: " + ctx.opRestarts);
-                    releaseLatch(node, ctx.op, isLeaf);
+                    releaseLatch(node, ctx.op, unsafeIsLeaf);
                     bufferCache.unpin(node);
                     unpins++;
 
@@ -1128,28 +993,29 @@
                 }
             } else { // isLeaf and !smFlag
                 switch (ctx.op) {
-                    case BTO_INSERT: {
+                    case INSERT: {
                         insertLeaf(node, pageId, ctx.pred.getLowKey(), ctx);
                     }
                         break;
 
-                    case BTO_DELETE: {
+                    case DELETE: {
                         deleteLeaf(node, pageId, ctx.pred.getLowKey(), ctx);
                     }
                         break;
 
-                    case BTO_SEARCH: {
-                        ctx.cursor.open(node, ctx.pred);
+                    case SEARCH: {
+                        ctx.cursorInitialState.setPage(node);
+                        ctx.cursor.open(ctx.cursorInitialState, ctx.pred);
                     }
                         break;
                 }
             }
-        } catch (BTreeException e) {
+        } catch (TreeIndexException e) {
             // System.out.println("BTREE EXCEPTION");
             // System.out.println(e.getMessage());
             // e.printStackTrace();
             if (!e.getHandled()) {
-                releaseLatch(node, ctx.op, isLeaf);
+                releaseLatch(node, ctx.op, unsafeIsLeaf);
                 bufferCache.unpin(node);
                 unpins++;
                 e.setHandled(true);
@@ -1159,7 +1025,7 @@
             // failure to pin a new node during a split
             System.out.println("ASTERIX EXCEPTION");
             e.printStackTrace();
-            releaseLatch(node, ctx.op, isLeaf);
+            releaseLatch(node, ctx.op, unsafeIsLeaf);
             bufferCache.unpin(node);
             unpins++;
             BTreeException propException = new BTreeException(e);
@@ -1173,28 +1039,29 @@
 
     private boolean bulkNewPage = false;
 
-    public final class BulkLoadContext {
+    public final class BulkLoadContext implements IIndexBulkLoadContext {
         public final int slotSize;
         public final int leafMaxBytes;
         public final int interiorMaxBytes;
-        public final SplitKey splitKey;
+        public final BTreeSplitKey splitKey;
         // we maintain a frontier of nodes for each level
         private final ArrayList<NodeFrontier> nodeFrontiers = new ArrayList<NodeFrontier>();
         private final IBTreeLeafFrame leafFrame;
         private final IBTreeInteriorFrame interiorFrame;
-        private final IBTreeMetaDataFrame metaFrame;
+        private final ITreeIndexMetaDataFrame metaFrame;
 
-        private final IBTreeTupleWriter tupleWriter;
+        private final ITreeIndexTupleWriter tupleWriter;
 
         public BulkLoadContext(float fillFactor, IBTreeLeafFrame leafFrame, IBTreeInteriorFrame interiorFrame,
-                IBTreeMetaDataFrame metaFrame) throws HyracksDataException {
+                ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException {
 
-            splitKey = new SplitKey(leafFrame.getTupleWriter().createTupleReference());
+            splitKey = new BTreeSplitKey(leafFrame.getTupleWriter().createTupleReference());
             tupleWriter = leafFrame.getTupleWriter();
 
             NodeFrontier leafFrontier = new NodeFrontier(leafFrame.createTupleReference());
-            leafFrontier.pageId = getFreePage(metaFrame);
-            leafFrontier.page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, leafFrontier.pageId), bulkNewPage);
+            leafFrontier.pageId = freePageManager.getFreePage(metaFrame);
+            leafFrontier.page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, leafFrontier.pageId),
+                    bulkNewPage);
             leafFrontier.page.acquireWriteLatch();
 
             interiorFrame.setPage(leafFrontier.page);
@@ -1216,7 +1083,7 @@
 
         private void addLevel() throws HyracksDataException {
             NodeFrontier frontier = new NodeFrontier(tupleWriter.createTupleReference());
-            frontier.pageId = getFreePage(metaFrame);
+            frontier.pageId = freePageManager.getFreePage(metaFrame);
             frontier.page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, frontier.pageId), bulkNewPage);
             frontier.page.acquireWriteLatch();
             frontier.lastTuple.setFieldCount(cmp.getKeyFieldCount());
@@ -1242,23 +1109,23 @@
         int spaceUsed = ctx.interiorFrame.getBuffer().capacity() - ctx.interiorFrame.getTotalFreeSpace();
         if (spaceUsed + spaceNeeded > ctx.interiorMaxBytes) {
 
-            SplitKey copyKey = ctx.splitKey.duplicate(ctx.leafFrame.getTupleWriter().createTupleReference());
+            BTreeSplitKey copyKey = ctx.splitKey.duplicate(ctx.leafFrame.getTupleWriter().createTupleReference());
             tuple = copyKey.getTuple();
 
-            frontier.lastTuple.resetByOffset(frontier.page.getBuffer(), ctx.interiorFrame
-                    .getTupleOffset(ctx.interiorFrame.getTupleCount() - 1));
+            frontier.lastTuple.resetByTupleOffset(frontier.page.getBuffer(),
+                    ctx.interiorFrame.getTupleOffset(ctx.interiorFrame.getTupleCount() - 1));
             int splitKeySize = ctx.tupleWriter.bytesRequired(frontier.lastTuple, 0, cmp.getKeyFieldCount());
             ctx.splitKey.initData(splitKeySize);
             ctx.tupleWriter
                     .writeTupleFields(frontier.lastTuple, 0, cmp.getKeyFieldCount(), ctx.splitKey.getBuffer(), 0);
-            ctx.splitKey.getTuple().resetByOffset(ctx.splitKey.getBuffer(), 0);
+            ctx.splitKey.getTuple().resetByTupleOffset(ctx.splitKey.getBuffer(), 0);
             ctx.splitKey.setLeftPage(frontier.pageId);
 
             ctx.interiorFrame.deleteGreatest(cmp);
 
             frontier.page.releaseWriteLatch();
             bufferCache.unpin(frontier.page);
-            frontier.pageId = getFreePage(ctx.metaFrame);
+            frontier.pageId = freePageManager.getFreePage(ctx.metaFrame);
 
             ctx.splitKey.setRightPage(frontier.pageId);
             propagateBulk(ctx, level + 1);
@@ -1279,19 +1146,23 @@
     }
 
     // assumes btree has been created and opened
-    public BulkLoadContext beginBulkLoad(float fillFactor, IBTreeLeafFrame leafFrame,
-            IBTreeInteriorFrame interiorFrame, IBTreeMetaDataFrame metaFrame) throws HyracksDataException {
+    @Override
+    public IIndexBulkLoadContext beginBulkLoad(float fillFactor, ITreeIndexFrame leafFrame,
+            ITreeIndexFrame interiorFrame, ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException {
 
         if (loaded)
             throw new HyracksDataException("Trying to bulk-load BTree but has BTree already been loaded.");
 
-        BulkLoadContext ctx = new BulkLoadContext(fillFactor, leafFrame, interiorFrame, metaFrame);
+        BulkLoadContext ctx = new BulkLoadContext(fillFactor, (IBTreeLeafFrame) leafFrame,
+                (IBTreeInteriorFrame) interiorFrame, metaFrame);
         ctx.nodeFrontiers.get(0).lastTuple.setFieldCount(cmp.getFieldCount());
         ctx.splitKey.getTuple().setFieldCount(cmp.getKeyFieldCount());
         return ctx;
     }
 
-    public void bulkLoadAddTuple(BulkLoadContext ctx, ITupleReference tuple) throws HyracksDataException {
+    @Override
+    public void bulkLoadAddTuple(IIndexBulkLoadContext ictx, ITupleReference tuple) throws HyracksDataException {
+        BulkLoadContext ctx = (BulkLoadContext) ictx;
         NodeFrontier leafFrontier = ctx.nodeFrontiers.get(0);
         IBTreeLeafFrame leafFrame = ctx.leafFrame;
 
@@ -1308,12 +1179,12 @@
             leafFrontier.lastTuple.resetByTupleIndex(leafFrame, leafFrame.getTupleCount() - 1);
             int splitKeySize = ctx.tupleWriter.bytesRequired(leafFrontier.lastTuple, 0, cmp.getKeyFieldCount());
             ctx.splitKey.initData(splitKeySize);
-            ctx.tupleWriter.writeTupleFields(leafFrontier.lastTuple, 0, cmp.getKeyFieldCount(), ctx.splitKey
-                    .getBuffer(), 0);
-            ctx.splitKey.getTuple().resetByOffset(ctx.splitKey.getBuffer(), 0);
+            ctx.tupleWriter.writeTupleFields(leafFrontier.lastTuple, 0, cmp.getKeyFieldCount(),
+                    ctx.splitKey.getBuffer(), 0);
+            ctx.splitKey.getTuple().resetByTupleOffset(ctx.splitKey.getBuffer(), 0);
             ctx.splitKey.setLeftPage(leafFrontier.pageId);
             int prevPageId = leafFrontier.pageId;
-            leafFrontier.pageId = getFreePage(ctx.metaFrame);
+            leafFrontier.pageId = freePageManager.getFreePage(ctx.metaFrame);
 
             leafFrame.setNextLeaf(leafFrontier.pageId);
             leafFrontier.page.releaseWriteLatch();
@@ -1322,7 +1193,8 @@
             ctx.splitKey.setRightPage(leafFrontier.pageId);
             propagateBulk(ctx, 1);
 
-            leafFrontier.page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, leafFrontier.pageId), bulkNewPage);
+            leafFrontier.page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, leafFrontier.pageId),
+                    bulkNewPage);
             leafFrontier.page.acquireWriteLatch();
             leafFrame.setPage(leafFrontier.page);
             leafFrame.initBuffer((byte) 0);
@@ -1340,18 +1212,29 @@
         // System.out.println(s);
     }
 
-    public void endBulkLoad(BulkLoadContext ctx) throws HyracksDataException {
+    @Override
+    public void endBulkLoad(IIndexBulkLoadContext ictx) throws HyracksDataException {
         // copy root
+        BulkLoadContext ctx = (BulkLoadContext) ictx;
         ICachedPage rootNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, rootPage), bulkNewPage);
         rootNode.acquireWriteLatch();
+        NodeFrontier lastNodeFrontier = ctx.nodeFrontiers.get(ctx.nodeFrontiers.size() - 1);
+        IBTreeInteriorFrame interiorFrame = ctx.interiorFrame;
         try {
-            ICachedPage toBeRoot = ctx.nodeFrontiers.get(ctx.nodeFrontiers.size() - 1).page;
+            ICachedPage toBeRoot = lastNodeFrontier.page;
             System.arraycopy(toBeRoot.getBuffer().array(), 0, rootNode.getBuffer().array(), 0, toBeRoot.getBuffer()
                     .capacity());
         } finally {
             rootNode.releaseWriteLatch();
             bufferCache.unpin(rootNode);
 
+            // register old root as free page
+            freePageManager.addFreePage(ctx.metaFrame, lastNodeFrontier.pageId);
+
+            // make old root a free page
+            interiorFrame.setPage(lastNodeFrontier.page);
+            interiorFrame.initBuffer(freePageManager.getFreePageLevelIndicator());
+
             // cleanup
             for (int i = 0; i < ctx.nodeFrontiers.size(); i++) {
                 ctx.nodeFrontiers.get(i).page.releaseWriteLatch();
@@ -1364,21 +1247,44 @@
         loaded = true;
     }
 
-    public BTreeOpContext createOpContext(BTreeOp op, IBTreeLeafFrame leafFrame, IBTreeInteriorFrame interiorFrame,
-            IBTreeMetaDataFrame metaFrame) {
-        // TODO: figure out better tree-height hint
-        return new BTreeOpContext(op, leafFrame, interiorFrame, metaFrame, 6);
+    @Override
+    public BTreeOpContext createOpContext(IndexOp op, ITreeIndexFrame leafFrame, ITreeIndexFrame interiorFrame,
+            ITreeIndexMetaDataFrame metaFrame) {
+        return new BTreeOpContext(op, (IBTreeLeafFrame) leafFrame, (IBTreeInteriorFrame) interiorFrame, metaFrame, 6);
     }
 
-    public IBTreeInteriorFrameFactory getInteriorFrameFactory() {
+    public ITreeIndexFrameFactory getInteriorFrameFactory() {
         return interiorFrameFactory;
     }
 
-    public IBTreeLeafFrameFactory getLeafFrameFactory() {
+    public ITreeIndexFrameFactory getLeafFrameFactory() {
         return leafFrameFactory;
     }
 
     public MultiComparator getMultiComparator() {
         return cmp;
     }
+
+    public IFreePageManager getFreePageManager() {
+        return freePageManager;
+    }
+
+    public int getRootPageId() {
+        return rootPage;
+    }
+
+    @Override
+    public void update(ITupleReference tuple, IndexOpContext ictx) throws Exception {
+        throw new Exception("BTree Update not implemented.");
+    }
+
+    @Override
+    public int getFieldCount() {
+        return cmp.getFieldCount();
+    }
+
+    @Override
+    public IndexType getIndexType() {
+        return IndexType.BTREE;
+    }
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeCursorInitialState.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeCursorInitialState.java
new file mode 100644
index 0000000..855f9e6
--- /dev/null
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeCursorInitialState.java
@@ -0,0 +1,21 @@
+package edu.uci.ics.hyracks.storage.am.btree.impls;
+
+import edu.uci.ics.hyracks.storage.am.common.api.ICursorInitialState;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+
+public class BTreeCursorInitialState implements ICursorInitialState {
+
+    private ICachedPage page;
+
+    public BTreeCursorInitialState(ICachedPage page) {
+        this.page = page;
+    }
+
+    public ICachedPage getPage() {
+        return page;
+    }
+
+    public void setPage(ICachedPage page) {
+        this.page = page;
+    }
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeException.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeException.java
index 7ec61ed..8019bcb 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeException.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeException.java
@@ -15,7 +15,9 @@
 
 package edu.uci.ics.hyracks.storage.am.btree.impls;
 
-public class BTreeException extends Exception {
+import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
+
+public class BTreeException extends TreeIndexException {
 
     private static final long serialVersionUID = 1L;
     private boolean handled = false;
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOpContext.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOpContext.java
index 84c11a2..6d65b14 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOpContext.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOpContext.java
@@ -15,41 +15,46 @@
 
 package edu.uci.ics.hyracks.storage.am.btree.impls;
 
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeCursor;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOpContext;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IntArrayList;
 
-public final class BTreeOpContext {
-    public final BTreeOp op;
+public final class BTreeOpContext implements IndexOpContext {
+    public final IndexOp op;
     public final IBTreeLeafFrame leafFrame;
     public final IBTreeInteriorFrame interiorFrame;
-    public final IBTreeMetaDataFrame metaFrame;
-    public IBTreeCursor cursor;
+    public final ITreeIndexMetaDataFrame metaFrame;
+    public ITreeIndexCursor cursor;
+    public BTreeCursorInitialState cursorInitialState;
     public RangePredicate pred;
-    public final SplitKey splitKey;
+    public final BTreeSplitKey splitKey;
     public int opRestarts = 0;
     public final IntArrayList pageLsns; // used like a stack
     public final IntArrayList smPages;
     public final IntArrayList freePages;
 
-    public BTreeOpContext(BTreeOp op, IBTreeLeafFrame leafFrame, IBTreeInteriorFrame interiorFrame,
-            IBTreeMetaDataFrame metaFrame, int treeHeightHint) {
+    public BTreeOpContext(IndexOp op, IBTreeLeafFrame leafFrame, IBTreeInteriorFrame interiorFrame,
+            ITreeIndexMetaDataFrame metaFrame, int treeHeightHint) {
         this.op = op;
         this.leafFrame = leafFrame;
         this.interiorFrame = interiorFrame;
         this.metaFrame = metaFrame;
 
         pageLsns = new IntArrayList(treeHeightHint, treeHeightHint);
-        if (op != BTreeOp.BTO_SEARCH) {
+        if (op != IndexOp.SEARCH && op != IndexOp.DISKORDERSCAN) {
             smPages = new IntArrayList(treeHeightHint, treeHeightHint);
             freePages = new IntArrayList(treeHeightHint, treeHeightHint);
             pred = new RangePredicate(true, null, null, true, true, null, null);
-            splitKey = new SplitKey(leafFrame.getTupleWriter().createTupleReference());
+            splitKey = new BTreeSplitKey(leafFrame.getTupleWriter().createTupleReference());
         } else {
             smPages = null;
             freePages = null;
             splitKey = null;
+            cursorInitialState = new BTreeCursorInitialState(null);
         }
     }
 
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/RangeSearchCursor.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeRangeSearchCursor.java
similarity index 87%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/RangeSearchCursor.java
rename to hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeRangeSearchCursor.java
index 2ef1905..4c7503d 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/RangeSearchCursor.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeRangeSearchCursor.java
@@ -17,15 +17,19 @@
 
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeCursor;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.ISearchPredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.ICursorInitialState;
+import edu.uci.ics.hyracks.storage.am.common.api.ISearchPredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
 
-public class RangeSearchCursor implements IBTreeCursor {
+public class BTreeRangeSearchCursor implements ITreeIndexCursor {
 
     private int fileId = -1;
     private ICachedPage page = null;
@@ -42,7 +46,7 @@
     private FindTupleNoExactMatchPolicy lowKeyFtp;
     private FindTupleNoExactMatchPolicy highKeyFtp;
 
-    private IBTreeTupleReference frameTuple;
+    private ITreeIndexTupleReference frameTuple;
 
     private RangePredicate pred;
     private MultiComparator lowKeyCmp;
@@ -50,7 +54,7 @@
     private ITupleReference lowKey;
     private ITupleReference highKey;
 
-    public RangeSearchCursor(IBTreeLeafFrame frame) {
+    public BTreeRangeSearchCursor(IBTreeLeafFrame frame) {
         this.frame = frame;
         this.frameTuple = frame.createTupleReference();
     }
@@ -83,7 +87,7 @@
         bufferCache.unpin(page);
 
         page = nextLeaf;
-        frame.setPage(page);
+        frame.setPage(page);       
     }
 
     @Override
@@ -170,14 +174,14 @@
     }
 
     @Override
-    public void open(ICachedPage page, ISearchPredicate searchPred) throws Exception {
+    public void open(ICursorInitialState initialState, ISearchPredicate searchPred) throws Exception {
         // in case open is called multiple times without closing
-        if (this.page != null) {
-            this.page.releaseReadLatch();
-            bufferCache.unpin(this.page);
+        if (page != null) {
+            page.releaseReadLatch();
+            bufferCache.unpin(page);
         }
 
-        this.page = page;
+        page = ((BTreeCursorInitialState) initialState).getPage();
         frame.setPage(page);
 
         pred = (RangePredicate) searchPred;
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/SplitKey.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeSplitKey.java
similarity index 79%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/SplitKey.java
rename to hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeSplitKey.java
index cf2fd74..e664e5b 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/SplitKey.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeSplitKey.java
@@ -17,18 +17,19 @@
 
 import java.nio.ByteBuffer;
 
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
 
-public class SplitKey {
+public class BTreeSplitKey implements ISplitKey {
     public byte[] data = null;
     public ByteBuffer buf = null;
-    public IBTreeTupleReference tuple;
+    public ITreeIndexTupleReference tuple;
     public int keySize = 0;
 
-    public SplitKey(IBTreeTupleReference tuple) {
+    public BTreeSplitKey(ITreeIndexTupleReference tuple) {
         this.tuple = tuple;
     }
-
+    
     public void initData(int keySize) {
         // try to reuse existing memory from a lower-level split if possible
         this.keySize = keySize;
@@ -42,7 +43,7 @@
             buf = ByteBuffer.wrap(data);
         }
 
-        tuple.resetByOffset(buf, 0);
+        tuple.resetByTupleOffset(buf, 0);
     }
 
     public void reset() {
@@ -54,7 +55,7 @@
         return buf;
     }
 
-    public IBTreeTupleReference getTuple() {
+    public ITreeIndexTupleReference getTuple() {
         return tuple;
     }
 
@@ -79,12 +80,12 @@
         buf.putInt(keySize + 4, rightPage);
     }
 
-    public SplitKey duplicate(IBTreeTupleReference copyTuple) {
-        SplitKey copy = new SplitKey(copyTuple);
+    public BTreeSplitKey duplicate(ITreeIndexTupleReference copyTuple) {
+        BTreeSplitKey copy = new BTreeSplitKey(copyTuple);
         copy.data = data.clone();
         copy.buf = ByteBuffer.wrap(copy.data);
         copy.tuple.setFieldCount(tuple.getFieldCount());
-        copy.tuple.resetByOffset(copy.buf, 0);
+        copy.tuple.resetByTupleOffset(copy.buf, 0);
         return copy;
     }
 }
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixPrefixTupleReference.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixPrefixTupleReference.java
index 8711a17..621281a 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixPrefixTupleReference.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixPrefixTupleReference.java
@@ -16,9 +16,9 @@
 package edu.uci.ics.hyracks.storage.am.btree.impls;
 
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
-import edu.uci.ics.hyracks.storage.am.btree.frames.FieldPrefixNSMLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleReference;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleReference;
 
 public class FieldPrefixPrefixTupleReference extends TypeAwareTupleReference {
 
@@ -28,13 +28,13 @@
 
     // assumes tuple index refers to prefix tuples
     @Override
-    public void resetByTupleIndex(IBTreeFrame frame, int tupleIndex) {
-        FieldPrefixNSMLeafFrame concreteFrame = (FieldPrefixNSMLeafFrame) frame;
+    public void resetByTupleIndex(ITreeIndexFrame frame, int tupleIndex) {
+        BTreeFieldPrefixNSMLeafFrame concreteFrame = (BTreeFieldPrefixNSMLeafFrame) frame;
         int prefixSlotOff = concreteFrame.slotManager.getPrefixSlotOff(tupleIndex);
         int prefixSlot = concreteFrame.getBuffer().getInt(prefixSlotOff);
         setFieldCount(concreteFrame.slotManager.decodeFirstSlotField(prefixSlot));
         tupleStartOff = concreteFrame.slotManager.decodeSecondSlotField(prefixSlot);
         buf = concreteFrame.getBuffer();
-        resetByOffset(buf, tupleStartOff);
+        resetByTupleOffset(buf, tupleStartOff);
     }
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixSlotManager.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixSlotManager.java
index 83a2d92..6f98c8c 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixSlotManager.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixSlotManager.java
@@ -18,9 +18,12 @@
 import java.nio.ByteBuffer;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
 import edu.uci.ics.hyracks.storage.am.btree.api.IPrefixSlotManager;
-import edu.uci.ics.hyracks.storage.am.btree.frames.FieldPrefixNSMLeafFrame;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
 public class FieldPrefixSlotManager implements IPrefixSlotManager {
 
@@ -30,7 +33,7 @@
     public static final int GREATEST_SLOT = 0x00FFFFFF;
 
     private ByteBuffer buf;
-    private FieldPrefixNSMLeafFrame frame;
+    private BTreeFieldPrefixNSMLeafFrame frame;
 
     public int decodeFirstSlotField(int slot) {
         return (slot & 0xFF000000) >>> 24;
@@ -45,7 +48,7 @@
     }
 
     // returns prefix slot number, or TUPLE_UNCOMPRESSED of no match was found
-    public int findPrefix(ITupleReference tuple, IBTreeTupleReference framePrefixTuple, MultiComparator multiCmp) {
+    public int findPrefix(ITupleReference tuple, ITreeIndexTupleReference framePrefixTuple, MultiComparator multiCmp) {
         int prefixMid;
         int prefixBegin = 0;
         int prefixEnd = frame.getPrefixTupleCount() - 1;
@@ -68,8 +71,8 @@
     }
 
     @Override
-    public int findSlot(ITupleReference searchKey, IBTreeTupleReference frameTuple,
-            IBTreeTupleReference framePrefixTuple, MultiComparator multiCmp, FindTupleMode mode,
+    public int findSlot(ITupleReference searchKey, ITreeIndexTupleReference frameTuple,
+            ITreeIndexTupleReference framePrefixTuple, MultiComparator multiCmp, FindTupleMode mode,
             FindTupleNoExactMatchPolicy matchPolicy) {
         if (frame.getTupleCount() <= 0)
             encodeSlotFields(TUPLE_UNCOMPRESSED, GREATEST_SLOT);
@@ -232,7 +235,7 @@
         }
     }
 
-    public void setFrame(FieldPrefixNSMLeafFrame frame) {
+    public void setFrame(BTreeFieldPrefixNSMLeafFrame frame) {
         this.frame = frame;
         this.buf = frame.getBuffer();
     }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixTupleReference.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixTupleReference.java
index c131e3f..9a655fc 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixTupleReference.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FieldPrefixTupleReference.java
@@ -2,26 +2,26 @@
 
 import java.nio.ByteBuffer;
 
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.frames.FieldPrefixNSMLeafFrame;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
 
-public class FieldPrefixTupleReference implements IBTreeTupleReference {
+public class FieldPrefixTupleReference implements ITreeIndexTupleReference {
 
-    private FieldPrefixNSMLeafFrame frame;
+    private BTreeFieldPrefixNSMLeafFrame frame;
     private int prefixTupleStartOff;
     private int suffixTupleStartOff;
     private int numPrefixFields;
     private int fieldCount;
-    private IBTreeTupleReference helperTuple;
+    private ITreeIndexTupleReference helperTuple;
 
-    public FieldPrefixTupleReference(IBTreeTupleReference helperTuple) {
+    public FieldPrefixTupleReference(ITreeIndexTupleReference helperTuple) {
         this.helperTuple = helperTuple;
     }
 
     @Override
-    public void resetByTupleIndex(IBTreeFrame frame, int tupleIndex) {
-        this.frame = (FieldPrefixNSMLeafFrame) frame;
+    public void resetByTupleIndex(ITreeIndexFrame frame, int tupleIndex) {
+        this.frame = (BTreeFieldPrefixNSMLeafFrame) frame;
 
         int tupleSlotOff = this.frame.slotManager.getTupleSlotOff(tupleIndex);
         int tupleSlot = this.frame.getBuffer().getInt(tupleSlotOff);
@@ -63,11 +63,11 @@
     public int getFieldLength(int fIdx) {
         if (fIdx < numPrefixFields) {
             helperTuple.setFieldCount(numPrefixFields);
-            helperTuple.resetByOffset(frame.getBuffer(), prefixTupleStartOff);
+            helperTuple.resetByTupleOffset(frame.getBuffer(), prefixTupleStartOff);
             return helperTuple.getFieldLength(fIdx);
         } else {
             helperTuple.setFieldCount(numPrefixFields, fieldCount - numPrefixFields);
-            helperTuple.resetByOffset(frame.getBuffer(), suffixTupleStartOff);
+            helperTuple.resetByTupleOffset(frame.getBuffer(), suffixTupleStartOff);
             return helperTuple.getFieldLength(fIdx - numPrefixFields);
         }
     }
@@ -76,18 +76,18 @@
     public int getFieldStart(int fIdx) {
         if (fIdx < numPrefixFields) {
             helperTuple.setFieldCount(numPrefixFields);
-            helperTuple.resetByOffset(frame.getBuffer(), prefixTupleStartOff);
+            helperTuple.resetByTupleOffset(frame.getBuffer(), prefixTupleStartOff);
             return helperTuple.getFieldStart(fIdx);
         } else {
             helperTuple.setFieldCount(numPrefixFields, fieldCount - numPrefixFields);
-            helperTuple.resetByOffset(frame.getBuffer(), suffixTupleStartOff);
+            helperTuple.resetByTupleOffset(frame.getBuffer(), suffixTupleStartOff);
             return helperTuple.getFieldStart(fIdx - numPrefixFields);
         }
     }
 
     // unsupported operation
     @Override
-    public void resetByOffset(ByteBuffer buf, int tupleStartOffset) {
+    public void resetByTupleOffset(ByteBuffer buf, int tupleStartOffset) {
         frame = null;
     }
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/NodeFrontier.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/NodeFrontier.java
index 83baa92..60f682c 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/NodeFrontier.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/NodeFrontier.java
@@ -15,15 +15,15 @@
 
 package edu.uci.ics.hyracks.storage.am.btree.impls;
 
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 
 public class NodeFrontier {
     public ICachedPage page;
     public int pageId;
-    public IBTreeTupleReference lastTuple;
+    public ITreeIndexTupleReference lastTuple;
 
-    public NodeFrontier(IBTreeTupleReference lastTuple) {
+    public NodeFrontier(ITreeIndexTupleReference lastTuple) {
         this.lastTuple = lastTuple;
     }
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/RangePredicate.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/RangePredicate.java
index 697b9ab..699f6a6 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/RangePredicate.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/RangePredicate.java
@@ -16,7 +16,8 @@
 package edu.uci.ics.hyracks.storage.am.btree.impls;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.ISearchPredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.ISearchPredicate;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
 public class RangePredicate implements ISearchPredicate {
 
diff --git a/hyracks-storage-am-invertedindex/.classpath b/hyracks-storage-am-common/.classpath
similarity index 100%
rename from hyracks-storage-am-invertedindex/.classpath
rename to hyracks-storage-am-common/.classpath
diff --git a/hyracks-storage-am-invertedindex/.project b/hyracks-storage-am-common/.project
similarity index 91%
copy from hyracks-storage-am-invertedindex/.project
copy to hyracks-storage-am-common/.project
index 9303fb7..ec47f6b 100644
--- a/hyracks-storage-am-invertedindex/.project
+++ b/hyracks-storage-am-common/.project
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <projectDescription>
-	<name>hyracks-storage-am-invertedindex</name>
+	<name>hyracks-storage-am-common</name>
 	<comment></comment>
 	<projects>
 	</projects>
diff --git a/hyracks-storage-am-common/.settings/org.eclipse.jdt.core.prefs b/hyracks-storage-am-common/.settings/org.eclipse.jdt.core.prefs
new file mode 100644
index 0000000..b37b3bb
--- /dev/null
+++ b/hyracks-storage-am-common/.settings/org.eclipse.jdt.core.prefs
@@ -0,0 +1,6 @@
+#Thu Jul 07 12:23:56 PDT 2011
+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
+org.eclipse.jdt.core.compiler.compliance=1.6
+org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
+org.eclipse.jdt.core.compiler.source=1.6
diff --git a/hyracks-storage-am-common/.settings/org.maven.ide.eclipse.prefs b/hyracks-storage-am-common/.settings/org.maven.ide.eclipse.prefs
new file mode 100644
index 0000000..7b5e618
--- /dev/null
+++ b/hyracks-storage-am-common/.settings/org.maven.ide.eclipse.prefs
@@ -0,0 +1,8 @@
+#Thu Jul 07 12:23:53 PDT 2011
+activeProfiles=
+eclipse.preferences.version=1
+fullBuildGoals=process-test-resources
+resolveWorkspaceProjects=true
+resourceFilterGoals=process-resources resources\:testResources
+skipCompilerPlugin=true
+version=1
diff --git a/hyracks-storage-am-common/pom.xml b/hyracks-storage-am-common/pom.xml
new file mode 100644
index 0000000..0d20126
--- /dev/null
+++ b/hyracks-storage-am-common/pom.xml
@@ -0,0 +1,56 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>edu.uci.ics.hyracks</groupId>
+  <artifactId>hyracks-storage-am-common</artifactId>
+  <version>0.1.7-SNAPSHOT</version>
+
+  <parent>
+    <groupId>edu.uci.ics.hyracks</groupId>
+    <artifactId>hyracks</artifactId>
+    <version>0.1.7-SNAPSHOT</version>
+  </parent>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>2.0.2</version>
+        <configuration>
+          <source>1.6</source>
+          <target>1.6</target>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+  <dependencies>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-api</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-storage-common</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-dataflow-common</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-dataflow-std</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>  
+  </dependencies>
+</project>
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrameFactory.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ICursorInitialState.java
similarity index 72%
copy from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrameFactory.java
copy to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ICursorInitialState.java
index 2912cf9..5f7c88d 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrameFactory.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ICursorInitialState.java
@@ -13,8 +13,12 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
-public interface IBTreeMetaDataFrameFactory {
-    public IBTreeMetaDataFrame getFrame();
-}
\ No newline at end of file
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+
+public interface ICursorInitialState {
+    public ICachedPage getPage();
+
+    public void setPage(ICachedPage page);
+}
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/IFreePageManager.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/IFreePageManager.java
new file mode 100644
index 0000000..7abc0e3
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/IFreePageManager.java
@@ -0,0 +1,25 @@
+package edu.uci.ics.hyracks.storage.am.common.api;
+
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+
+public interface IFreePageManager {
+    public int getFreePage(ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException;
+
+    public void addFreePage(ITreeIndexMetaDataFrame metaFrame, int freePage) throws HyracksDataException;
+
+    public int getMaxPage(ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException;
+
+    public void init(ITreeIndexMetaDataFrame metaFrame, int currentMaxPage) throws HyracksDataException;
+
+    public ITreeIndexMetaDataFrameFactory getMetaDataFrameFactory();
+
+    // required to return negative values
+    public byte getMetaPageLevelIndicator();
+
+    public byte getFreePageLevelIndicator();
+
+    // determined by examining level indicator
+    public boolean isMetaPage(ITreeIndexMetaDataFrame metaFrame);
+
+    public boolean isFreePage(ITreeIndexMetaDataFrame metaFrame);
+}
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/IIndexBulkLoadContext.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/IIndexBulkLoadContext.java
new file mode 100644
index 0000000..a896d80
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/IIndexBulkLoadContext.java
@@ -0,0 +1,4 @@
+package edu.uci.ics.hyracks.storage.am.common.api;
+
+public interface IIndexBulkLoadContext {
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/ISearchPredicate.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISearchPredicate.java
similarity index 76%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/ISearchPredicate.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISearchPredicate.java
index 255c370..f4836e0 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/ISearchPredicate.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISearchPredicate.java
@@ -13,10 +13,14 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
 import java.io.Serializable;
 
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+
 public interface ISearchPredicate extends Serializable {
-    public boolean isForward();
-}
+    public MultiComparator getLowKeyComparator();
+
+    public MultiComparator getHighKeyComparator();
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/ISlotManager.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISlotManager.java
similarity index 71%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/ISlotManager.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISlotManager.java
index c1d4e0a..29646e7 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/ISlotManager.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISlotManager.java
@@ -13,17 +13,17 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleMode;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleNoExactMatchPolicy;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
 public interface ISlotManager {
-    public void setFrame(IBTreeFrame frame);
+    public void setFrame(ITreeIndexFrame frame);
 
-    public int findTupleIndex(ITupleReference searchKey, IBTreeTupleReference frameTuple, MultiComparator multiCmp,
+    public int findTupleIndex(ITupleReference searchKey, ITreeIndexTupleReference frameTuple, MultiComparator multiCmp,
             FindTupleMode mode, FindTupleNoExactMatchPolicy matchPolicy);
 
     public int insertSlot(int tupleIndex, int tupleOff);
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISplitKey.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISplitKey.java
new file mode 100644
index 0000000..246c09d
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ISplitKey.java
@@ -0,0 +1,25 @@
+package edu.uci.ics.hyracks.storage.am.common.api;
+
+import java.nio.ByteBuffer;
+
+public interface ISplitKey {
+    public void initData(int keySize);
+
+    public void reset();
+
+    public ByteBuffer getBuffer();
+
+    public ITreeIndexTupleReference getTuple();
+
+    public int getLeftPage();
+
+    public int getRightPage();
+
+    public void setLeftPage(int leftPage);
+
+    public void setRightPage(int rightPage);
+
+    public void setPages(int leftPage, int rightPage);
+
+    public ISplitKey duplicate(ITreeIndexTupleReference copyTuple);
+}
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndex.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndex.java
new file mode 100644
index 0000000..2d77f06
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndex.java
@@ -0,0 +1,52 @@
+package edu.uci.ics.hyracks.storage.am.common.api;
+
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOpContext;
+
+public interface ITreeIndex {
+    // init:
+
+    public void create(int indexFileId, ITreeIndexFrame leafFrame, ITreeIndexMetaDataFrame metaFrame) throws Exception;
+
+    public void open(int indexFileId);
+
+    // operations:
+
+    public void insert(ITupleReference tuple, IndexOpContext ictx) throws Exception;
+
+    public void update(ITupleReference tuple, IndexOpContext ictx) throws Exception;
+
+    public void delete(ITupleReference tuple, IndexOpContext ictx) throws Exception;
+
+    public IndexOpContext createOpContext(IndexOp op, ITreeIndexFrame leafFrame, ITreeIndexFrame interiorFrame,
+            ITreeIndexMetaDataFrame metaFrame);
+
+    // bulk loading:
+
+    public IIndexBulkLoadContext beginBulkLoad(float fillFactor, ITreeIndexFrame leafFrame,
+            ITreeIndexFrame interiorFrame, ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException;
+
+    public void bulkLoadAddTuple(IIndexBulkLoadContext ictx, ITupleReference tuple) throws HyracksDataException;
+
+    public void endBulkLoad(IIndexBulkLoadContext ictx) throws HyracksDataException;
+
+    // search:
+    public void diskOrderScan(ITreeIndexCursor icursor, ITreeIndexFrame leafFrame, ITreeIndexMetaDataFrame metaFrame,
+            IndexOpContext ictx) throws HyracksDataException;
+
+    // utility:
+
+    public IFreePageManager getFreePageManager();
+
+    public int getRootPageId();
+
+    public ITreeIndexFrameFactory getLeafFrameFactory();
+
+    public ITreeIndexFrameFactory getInteriorFrameFactory();
+
+    public int getFieldCount();
+
+    public IndexType getIndexType();
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeCursor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexCursor.java
similarity index 85%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeCursor.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexCursor.java
index 8934921..22b2b6f 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeCursor.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexCursor.java
@@ -13,20 +13,20 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 
-public interface IBTreeCursor {
+public interface ITreeIndexCursor {
     public void reset();
 
     public boolean hasNext() throws Exception;
 
     public void next() throws Exception;
 
-    public void open(ICachedPage page, ISearchPredicate searchPred) throws Exception;
+    public void open(ICursorInitialState initialState, ISearchPredicate searchPred) throws Exception;
 
     public ICachedPage getPage();
 
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeFrame.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrame.java
similarity index 74%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeFrame.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrame.java
index 0e15903..246efe4 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeFrame.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrame.java
@@ -13,32 +13,34 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
 import java.nio.ByteBuffer;
 
 import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SpaceStatus;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SplitKey;
+import edu.uci.ics.hyracks.storage.am.common.frames.FrameOpSpaceStatus;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 
-public interface IBTreeFrame {
+public interface ITreeIndexFrame {
     public void setPage(ICachedPage page);
 
     public ICachedPage getPage();
 
     public ByteBuffer getBuffer();
 
-    public void insert(ITupleReference tuple, MultiComparator cmp) throws Exception;
+    public int findTupleIndex(ITupleReference tuple, MultiComparator cmp) throws Exception;
+
+    public void insert(ITupleReference tuple, MultiComparator cmp, int tupleIndex) throws Exception;
 
     public void update(int rid, ITupleReference tuple) throws Exception;
 
     public void delete(ITupleReference tuple, MultiComparator cmp, boolean exactDelete) throws Exception;
 
-    public void compact(MultiComparator cmp);
+    // returns true if slots were modified, false otherwise
+    public boolean compact(MultiComparator cmp);
 
     public boolean compress(MultiComparator cmp) throws HyracksDataException;
 
@@ -47,9 +49,9 @@
     public int getTupleCount();
 
     // assumption: page must be write-latched at this point
-    public SpaceStatus hasSpaceInsert(ITupleReference tuple, MultiComparator cmp);
+    public FrameOpSpaceStatus hasSpaceInsert(ITupleReference tuple, MultiComparator cmp);
 
-    public SpaceStatus hasSpaceUpdate(int rid, ITupleReference tuple, MultiComparator cmp);
+    public FrameOpSpaceStatus hasSpaceUpdate(int rid, ITupleReference tuple, MultiComparator cmp);
 
     public int getTupleOffset(int slotNum);
 
@@ -65,10 +67,9 @@
     public String printKeys(MultiComparator cmp, ISerializerDeserializer[] fields) throws HyracksDataException;
 
     // TODO; what if tuples more than half-page size?
-    public int split(IBTreeFrame rightFrame, ITupleReference tuple, MultiComparator cmp, SplitKey splitKey)
+    public int split(ITreeIndexFrame rightFrame, ITupleReference tuple, MultiComparator cmp, ISplitKey splitKey)
             throws Exception;
 
-    // TODO: check if we do something nicer than returning object
     public ISlotManager getSlotManager();
 
     // ATTENTION: in b-tree operations it may not always be possible to
@@ -77,6 +78,8 @@
     // values when given the same ByteBuffer for the functions below
     public boolean isLeaf();
 
+    public boolean isInterior();
+
     public byte getLevel();
 
     public void setLevel(byte level);
@@ -85,8 +88,6 @@
 
     public void setSmFlag(boolean smFlag);
 
-    public void insertSorted(ITupleReference tuple, MultiComparator cmp) throws HyracksDataException;
-
     public int getSlotSize();
 
     // TODO: should be removed after new tuple format
@@ -97,6 +98,7 @@
 
     public void setFreeSpaceOff(int freeSpace);
 
-    public IBTreeTupleWriter getTupleWriter();
+    public ITreeIndexTupleWriter getTupleWriter();
 
+    public int getPageHeaderSize();
 }
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrameFactory.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrameFactory.java
new file mode 100644
index 0000000..83b95b6
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexFrameFactory.java
@@ -0,0 +1,7 @@
+package edu.uci.ics.hyracks.storage.am.common.api;
+
+import java.io.Serializable;
+
+public interface ITreeIndexFrameFactory extends Serializable {
+    public ITreeIndexFrame createFrame();
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrame.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexMetaDataFrame.java
similarity index 91%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrame.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexMetaDataFrame.java
index 58739e2..bbd03d6 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrame.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexMetaDataFrame.java
@@ -13,11 +13,11 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 
-public interface IBTreeMetaDataFrame {
+public interface ITreeIndexMetaDataFrame {
     public void initBuffer(int level);
 
     public void setPage(ICachedPage page);
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrameFactory.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexMetaDataFrameFactory.java
similarity index 80%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrameFactory.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexMetaDataFrameFactory.java
index 2912cf9..6fd88e8 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeMetaDataFrameFactory.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexMetaDataFrameFactory.java
@@ -13,8 +13,8 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
-public interface IBTreeMetaDataFrameFactory {
-    public IBTreeMetaDataFrame getFrame();
+public interface ITreeIndexMetaDataFrameFactory {
+    public ITreeIndexMetaDataFrame createFrame();
 }
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexTupleReference.java
similarity index 75%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexTupleReference.java
index 38d6217..d2c2df4 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexTupleReference.java
@@ -13,18 +13,18 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
 import java.nio.ByteBuffer;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 
-public interface IBTreeTupleReference extends ITupleReference {
+public interface ITreeIndexTupleReference extends ITupleReference {
     public void setFieldCount(int fieldCount);
 
     public void setFieldCount(int fieldStartIndex, int fieldCount);
 
-    public void resetByOffset(ByteBuffer buf, int tupleStartOffset);
+    public void resetByTupleOffset(ByteBuffer buf, int tupleStartOffset);
 
-    public void resetByTupleIndex(IBTreeFrame frame, int tupleIndex);
+    public void resetByTupleIndex(ITreeIndexFrame frame, int tupleIndex);
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleWriter.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexTupleWriter.java
similarity index 89%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleWriter.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexTupleWriter.java
index d8cb9af..39577ea 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleWriter.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexTupleWriter.java
@@ -13,13 +13,13 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
 import java.nio.ByteBuffer;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 
-public interface IBTreeTupleWriter {
+public interface ITreeIndexTupleWriter {
     public int writeTuple(ITupleReference tuple, ByteBuffer targetBuf, int targetOff);
 
     public int bytesRequired(ITupleReference tuple);
@@ -33,5 +33,5 @@
     // writer
     // the main idea is that the format of the written tuple may not be the same
     // as the format written by this writer
-    public IBTreeTupleReference createTupleReference();
+    public ITreeIndexTupleReference createTupleReference();
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrameFactory.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexTupleWriterFactory.java
similarity index 78%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrameFactory.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexTupleWriterFactory.java
index 50733de..bd7bfda 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrameFactory.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/ITreeIndexTupleWriterFactory.java
@@ -13,10 +13,10 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
 import java.io.Serializable;
 
-public interface IBTreeLeafFrameFactory extends Serializable {
-    public IBTreeLeafFrame getFrame();
-}
\ No newline at end of file
+public interface ITreeIndexTupleWriterFactory extends Serializable {
+    public ITreeIndexTupleWriter createTupleWriter();
+}
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/IndexType.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/IndexType.java
new file mode 100644
index 0000000..d5f9f44
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/IndexType.java
@@ -0,0 +1,5 @@
+package edu.uci.ics.hyracks.storage.am.common.api;
+
+public enum IndexType {
+    BTREE, RTREE, INVERTED
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleWriterFactory.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/TreeIndexException.java
similarity index 61%
copy from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleWriterFactory.java
copy to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/TreeIndexException.java
index 3b06153..ad3db58 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleWriterFactory.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/api/TreeIndexException.java
@@ -13,18 +13,26 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.tuples;
+package edu.uci.ics.hyracks.storage.am.common.api;
 
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriterFactory;
-
-public class SimpleTupleWriterFactory implements IBTreeTupleWriterFactory {
+public class TreeIndexException extends Exception {
 
     private static final long serialVersionUID = 1L;
+    private boolean handled = false;
 
-    @Override
-    public IBTreeTupleWriter createTupleWriter() {
-        return new SimpleTupleWriter();
+    public TreeIndexException(Exception e) {
+        super(e);
     }
 
+    public TreeIndexException(String message) {
+        super(message);
+    }
+
+    public void setHandled(boolean handled) {
+        this.handled = handled;
+    }
+
+    public boolean getHandled() {
+        return handled;
+    }
 }
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/AbstractTreeIndexOperatorDescriptor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/AbstractTreeIndexOperatorDescriptor.java
new file mode 100644
index 0000000..c905eb2
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/AbstractTreeIndexOperatorDescriptor.java
@@ -0,0 +1,110 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.job.JobSpecification;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+
+public abstract class AbstractTreeIndexOperatorDescriptor extends AbstractSingleActivityOperatorDescriptor implements
+        ITreeIndexOperatorDescriptorHelper {
+
+    private static final long serialVersionUID = 1L;
+
+    protected final IFileSplitProvider fileSplitProvider;
+
+    protected final IBinaryComparatorFactory[] comparatorFactories;
+
+    protected final ITreeIndexFrameFactory interiorFrameFactory;
+    protected final ITreeIndexFrameFactory leafFrameFactory;
+
+    protected final IStorageManagerInterface storageManager;
+    protected final IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider;
+
+    protected final ITypeTrait[] typeTraits;
+
+    protected final ITreeIndexOpHelperFactory opHelperFactory;
+
+    public AbstractTreeIndexOperatorDescriptor(JobSpecification spec, int inputArity, int outputArity,
+            RecordDescriptor recDesc, IStorageManagerInterface storageManager,
+            IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider, IFileSplitProvider fileSplitProvider,
+            ITreeIndexFrameFactory interiorFrameFactory, ITreeIndexFrameFactory leafFrameFactory,
+            ITypeTrait[] typeTraits, IBinaryComparatorFactory[] comparatorFactories,
+            ITreeIndexOpHelperFactory opHelperFactory) {
+        super(spec, inputArity, outputArity);
+        this.fileSplitProvider = fileSplitProvider;
+        this.storageManager = storageManager;
+        this.treeIndexRegistryProvider = treeIndexRegistryProvider;
+        this.interiorFrameFactory = interiorFrameFactory;
+        this.leafFrameFactory = leafFrameFactory;
+        this.typeTraits = typeTraits;
+        this.comparatorFactories = comparatorFactories;
+        this.opHelperFactory = opHelperFactory;
+        if (outputArity > 0)
+            recordDescriptors[0] = recDesc;
+    }
+
+    @Override
+    public IFileSplitProvider getTreeIndexFileSplitProvider() {
+        return fileSplitProvider;
+    }
+
+    @Override
+    public IBinaryComparatorFactory[] getTreeIndexComparatorFactories() {
+        return comparatorFactories;
+    }
+
+    @Override
+    public ITypeTrait[] getTreeIndexTypeTraits() {
+        return typeTraits;
+    }
+
+    @Override
+    public ITreeIndexFrameFactory getTreeIndexInteriorFactory() {
+        return interiorFrameFactory;
+    }
+
+    @Override
+    public ITreeIndexFrameFactory getTreeIndexLeafFactory() {
+        return leafFrameFactory;
+    }
+
+    @Override
+    public IStorageManagerInterface getStorageManager() {
+        return storageManager;
+    }
+
+    @Override
+    public IIndexRegistryProvider<ITreeIndex> getTreeIndexRegistryProvider() {
+        return treeIndexRegistryProvider;
+    }
+
+    @Override
+    public RecordDescriptor getRecordDescriptor() {
+        return recordDescriptors[0];
+    }
+
+    @Override
+    public ITreeIndexOpHelperFactory getTreeIndexOpHelperFactory() {
+        return opHelperFactory;
+    }
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/IBTreeRegistryProvider.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/IIndexRegistryProvider.java
similarity index 77%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/IBTreeRegistryProvider.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/IIndexRegistryProvider.java
index 7b66d0a..aadcaf9 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/IBTreeRegistryProvider.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/IIndexRegistryProvider.java
@@ -13,12 +13,12 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
 
 import java.io.Serializable;
 
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
 
-public interface IBTreeRegistryProvider extends Serializable {
-    public BTreeRegistry getBTreeRegistry(IHyracksStageletContext ctx);
+public interface IIndexRegistryProvider<IndexType> extends Serializable {
+    public IndexRegistry<IndexType> getRegistry(IHyracksStageletContext ctx);
 }
\ No newline at end of file
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/ITreeIndexOpHelperFactory.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/ITreeIndexOpHelperFactory.java
new file mode 100644
index 0000000..fa37fab
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/ITreeIndexOpHelperFactory.java
@@ -0,0 +1,10 @@
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import java.io.Serializable;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+
+public interface ITreeIndexOpHelperFactory extends Serializable {
+    public TreeIndexOpHelper createTreeIndexOpHelper(ITreeIndexOperatorDescriptorHelper opDesc,
+            final IHyracksStageletContext ctx, int partition, IndexHelperOpenMode mode);
+}
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/ITreeIndexOperatorDescriptorHelper.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/ITreeIndexOperatorDescriptorHelper.java
new file mode 100644
index 0000000..6ca4529
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/ITreeIndexOperatorDescriptorHelper.java
@@ -0,0 +1,30 @@
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import edu.uci.ics.hyracks.api.dataflow.IActivityNode;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+
+public interface ITreeIndexOperatorDescriptorHelper extends IActivityNode {
+    public IFileSplitProvider getTreeIndexFileSplitProvider();
+
+    public IBinaryComparatorFactory[] getTreeIndexComparatorFactories();
+
+    public ITypeTrait[] getTreeIndexTypeTraits();
+
+    public ITreeIndexFrameFactory getTreeIndexInteriorFactory();
+
+    public ITreeIndexFrameFactory getTreeIndexLeafFactory();
+
+    public IStorageManagerInterface getStorageManager();
+
+    public IIndexRegistryProvider<ITreeIndex> getTreeIndexRegistryProvider();
+
+    public RecordDescriptor getRecordDescriptor();
+
+    public ITreeIndexOpHelperFactory getTreeIndexOpHelperFactory();
+}
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/IndexHelperOpenMode.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/IndexHelperOpenMode.java
new file mode 100644
index 0000000..aa41184
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/IndexHelperOpenMode.java
@@ -0,0 +1,5 @@
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+public enum IndexHelperOpenMode {
+    OPEN, CREATE, ENLIST
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeRegistry.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/IndexRegistry.java
similarity index 74%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeRegistry.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/IndexRegistry.java
index 9b90e22..de00d5a 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeRegistry.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/IndexRegistry.java
@@ -13,24 +13,21 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
 
 import java.util.HashMap;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
 
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
+public class IndexRegistry<IndexType> {
 
-public class BTreeRegistry {
-
-    private HashMap<Integer, BTree> map = new HashMap<Integer, BTree>();
+    private HashMap<Integer, IndexType> map = new HashMap<Integer, IndexType>();
     private Lock registryLock = new ReentrantLock();
 
-    public BTree get(int fileId) {
+    public IndexType get(int fileId) {
         return map.get(fileId);
     }
 
-    // TODO: not very high concurrency, but good enough for now
     public void lock() {
         registryLock.lock();
     }
@@ -39,8 +36,8 @@
         registryLock.unlock();
     }
 
-    public void register(int fileId, BTree btree) {
-        map.put(fileId, btree);
+    public void register(int fileId, IndexType index) {
+        map.put(fileId, index);
     }
 
     public void unregister(int fileId) {
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/PermutingFrameTupleReference.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/PermutingFrameTupleReference.java
similarity index 96%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/PermutingFrameTupleReference.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/PermutingFrameTupleReference.java
index a3f343a..3db9db2 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/PermutingFrameTupleReference.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/PermutingFrameTupleReference.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
 
 import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.IFrameTupleReference;
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeBulkLoadOperatorDescriptor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorDescriptor.java
similarity index 60%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeBulkLoadOperatorDescriptor.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorDescriptor.java
index a4c4b61..7d585b3 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeBulkLoadOperatorDescriptor.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorDescriptor.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
 
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
 import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
@@ -23,23 +23,24 @@
 import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
 import edu.uci.ics.hyracks.api.job.JobSpecification;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
-public class BTreeBulkLoadOperatorDescriptor extends AbstractBTreeOperatorDescriptor {
+public class TreeIndexBulkLoadOperatorDescriptor extends AbstractTreeIndexOperatorDescriptor {
 
     private static final long serialVersionUID = 1L;
 
     private final int[] fieldPermutation;
     private final float fillFactor;
 
-    public BTreeBulkLoadOperatorDescriptor(JobSpecification spec, IStorageManagerInterface storageManager,
-            IBTreeRegistryProvider btreeRegistryProvider, IFileSplitProvider fileSplitProvider,
-            IBTreeInteriorFrameFactory interiorFactory, IBTreeLeafFrameFactory leafFactory, ITypeTrait[] typeTraits,
-            IBinaryComparatorFactory[] comparatorFactories, int[] fieldPermutation, float fillFactor) {
-        super(spec, 1, 0, null, storageManager, btreeRegistryProvider, fileSplitProvider, interiorFactory, leafFactory,
-                typeTraits, comparatorFactories);
+    public TreeIndexBulkLoadOperatorDescriptor(JobSpecification spec, IStorageManagerInterface storageManager,
+            IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider, IFileSplitProvider fileSplitProvider,
+            ITreeIndexFrameFactory interiorFrameFactory, ITreeIndexFrameFactory leafFrameFactory,
+            ITypeTrait[] typeTraits, IBinaryComparatorFactory[] comparatorFactories, int[] fieldPermutation,
+            float fillFactor, ITreeIndexOpHelperFactory opHelperFactory) {
+        super(spec, 1, 0, null, storageManager, treeIndexRegistryProvider, fileSplitProvider, interiorFrameFactory,
+                leafFrameFactory, typeTraits, comparatorFactories, opHelperFactory);
         this.fieldPermutation = fieldPermutation;
         this.fillFactor = fillFactor;
     }
@@ -47,7 +48,7 @@
     @Override
     public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
             IRecordDescriptorProvider recordDescProvider, int partition, int nPartitions) {
-        return new BTreeBulkLoadOperatorNodePushable(this, ctx, partition, fieldPermutation, fillFactor,
+        return new TreeIndexBulkLoadOperatorNodePushable(this, ctx, partition, fieldPermutation, fillFactor,
                 recordDescProvider);
     }
 }
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorNodePushable.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorNodePushable.java
new file mode 100644
index 0000000..2001039
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexBulkLoadOperatorNodePushable.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputSinkOperatorNodePushable;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexBulkLoadContext;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrame;
+
+public class TreeIndexBulkLoadOperatorNodePushable extends AbstractUnaryInputSinkOperatorNodePushable {
+    private float fillFactor;
+    private final TreeIndexOpHelper treeIndexOpHelper;
+    private FrameTupleAccessor accessor;
+    private IIndexBulkLoadContext bulkLoadCtx;
+
+    private IRecordDescriptorProvider recordDescProvider;
+
+    private PermutingFrameTupleReference tuple = new PermutingFrameTupleReference();
+
+    public TreeIndexBulkLoadOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc,
+            IHyracksStageletContext ctx, int partition, int[] fieldPermutation, float fillFactor,
+            IRecordDescriptorProvider recordDescProvider) {
+        treeIndexOpHelper = opDesc.getTreeIndexOpHelperFactory().createTreeIndexOpHelper(opDesc, ctx, partition,
+                IndexHelperOpenMode.CREATE);
+        this.fillFactor = fillFactor;
+        this.recordDescProvider = recordDescProvider;
+        tuple.setFieldPermutation(fieldPermutation);
+    }
+
+    @Override
+    public void open() throws HyracksDataException {
+        AbstractTreeIndexOperatorDescriptor opDesc = (AbstractTreeIndexOperatorDescriptor) treeIndexOpHelper
+                .getOperatorDescriptor();
+        RecordDescriptor recDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getOperatorId(), 0);
+        accessor = new FrameTupleAccessor(treeIndexOpHelper.getHyracksStageletContext().getFrameSize(), recDesc);
+        ITreeIndexMetaDataFrame metaFrame = new LIFOMetaDataFrame();
+        try {
+            treeIndexOpHelper.init();
+            treeIndexOpHelper.getTreeIndex().open(treeIndexOpHelper.getIndexFileId());
+            bulkLoadCtx = treeIndexOpHelper.getTreeIndex().beginBulkLoad(fillFactor, treeIndexOpHelper.getLeafFrame(),
+                    treeIndexOpHelper.getInteriorFrame(), metaFrame);
+        } catch (Exception e) {
+            // cleanup in case of failure
+            treeIndexOpHelper.deinit();
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
+        accessor.reset(buffer);
+        int tupleCount = accessor.getTupleCount();
+        for (int i = 0; i < tupleCount; i++) {
+            tuple.reset(accessor, i);
+            treeIndexOpHelper.getTreeIndex().bulkLoadAddTuple(bulkLoadCtx, tuple);
+        }
+    }
+
+    @Override
+    public void close() throws HyracksDataException {
+        try {
+            treeIndexOpHelper.getTreeIndex().endBulkLoad(bulkLoadCtx);
+        } finally {
+            treeIndexOpHelper.deinit();
+        }
+    }
+
+    @Override
+    public void flush() throws HyracksDataException {
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDiskOrderScanOperatorDescriptor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDiskOrderScanOperatorDescriptor.java
new file mode 100644
index 0000000..73b5323
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDiskOrderScanOperatorDescriptor.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
+import edu.uci.ics.hyracks.api.job.JobSpecification;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+
+public class TreeIndexDiskOrderScanOperatorDescriptor extends AbstractTreeIndexOperatorDescriptor {
+
+    private static final long serialVersionUID = 1L;
+
+    public TreeIndexDiskOrderScanOperatorDescriptor(JobSpecification spec, RecordDescriptor recDesc,
+            IStorageManagerInterface storageManager, IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider,
+            IFileSplitProvider fileSplitProvider, ITreeIndexFrameFactory interiorFrameFactory,
+            ITreeIndexFrameFactory leafFrameFactory, ITypeTrait[] typeTraits, ITreeIndexOpHelperFactory opHelperFactory) {
+        super(spec, 0, 1, recDesc, storageManager, treeIndexRegistryProvider, fileSplitProvider, interiorFrameFactory,
+                leafFrameFactory, typeTraits, null, opHelperFactory);
+    }
+
+    @Override
+    public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
+            IRecordDescriptorProvider recordDescProvider, int partition, int nPartitions) {
+        return new TreeIndexDiskOrderScanOperatorNodePushable(this, ctx, partition);
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDiskOrderScanOperatorNodePushable.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDiskOrderScanOperatorNodePushable.java
new file mode 100644
index 0000000..415b9e3
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDiskOrderScanOperatorNodePushable.java
@@ -0,0 +1,104 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import java.io.DataOutput;
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryOutputSourceOperatorNodePushable;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOpContext;
+
+public class TreeIndexDiskOrderScanOperatorNodePushable extends AbstractUnaryOutputSourceOperatorNodePushable {
+    private final TreeIndexOpHelper treeIndexOpHelper;
+
+    public TreeIndexDiskOrderScanOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc,
+            IHyracksStageletContext ctx, int partition) {
+        treeIndexOpHelper = opDesc.getTreeIndexOpHelperFactory().createTreeIndexOpHelper(opDesc, ctx, partition,
+                IndexHelperOpenMode.OPEN);
+    }
+
+    @Override
+    public void initialize() throws HyracksDataException {
+
+        ITreeIndexFrame cursorFrame = treeIndexOpHelper.getOperatorDescriptor().getTreeIndexLeafFactory().createFrame();
+        ITreeIndexCursor cursor = treeIndexOpHelper.createDiskOrderScanCursor(cursorFrame);
+        ITreeIndexMetaDataFrame metaFrame = new LIFOMetaDataFrame();
+
+        IndexOpContext diskOrderScanOpCtx = treeIndexOpHelper.getTreeIndex().createOpContext(IndexOp.DISKORDERSCAN,
+                cursorFrame, null, null);
+        try {
+
+            treeIndexOpHelper.init();
+
+            try {
+                treeIndexOpHelper.getTreeIndex().diskOrderScan(cursor, cursorFrame, metaFrame, diskOrderScanOpCtx);
+
+                int fieldCount = treeIndexOpHelper.getTreeIndex().getFieldCount();
+                ByteBuffer frame = treeIndexOpHelper.getHyracksStageletContext().allocateFrame();
+                FrameTupleAppender appender = new FrameTupleAppender(treeIndexOpHelper.getHyracksStageletContext()
+                        .getFrameSize());
+                appender.reset(frame, true);
+                ArrayTupleBuilder tb = new ArrayTupleBuilder(fieldCount);
+                DataOutput dos = tb.getDataOutput();
+
+                while (cursor.hasNext()) {
+                    tb.reset();
+                    cursor.next();
+
+                    ITupleReference frameTuple = cursor.getTuple();
+                    for (int i = 0; i < frameTuple.getFieldCount(); i++) {
+                        dos.write(frameTuple.getFieldData(i), frameTuple.getFieldStart(i), frameTuple.getFieldLength(i));
+                        tb.addFieldEndOffset();
+                    }
+
+                    if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
+                        FrameUtils.flushFrame(frame, writer);
+                        appender.reset(frame, true);
+                        if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
+                            throw new IllegalStateException();
+                        }
+                    }
+                }
+
+                if (appender.getTupleCount() > 0) {
+                    FrameUtils.flushFrame(frame, writer);
+                }
+            } finally {
+                cursor.close();
+                writer.close();
+            }
+
+        } catch (Exception e) {
+            deinitialize();
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void deinitialize() throws HyracksDataException {
+        treeIndexOpHelper.deinit();
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorDescriptor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDropOperatorDescriptor.java
similarity index 69%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorDescriptor.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDropOperatorDescriptor.java
index 970d44a..2cfa905 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorDescriptor.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDropOperatorDescriptor.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
 
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
 import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
@@ -22,27 +22,29 @@
 import edu.uci.ics.hyracks.api.job.JobSpecification;
 import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
-public class BTreeDropOperatorDescriptor extends AbstractSingleActivityOperatorDescriptor {
+public class TreeIndexDropOperatorDescriptor extends AbstractSingleActivityOperatorDescriptor {
 
     private static final long serialVersionUID = 1L;
 
     private IStorageManagerInterface storageManager;
-    private IBTreeRegistryProvider btreeRegistryProvider;
+    private IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider;
     private IFileSplitProvider fileSplitProvider;
 
-    public BTreeDropOperatorDescriptor(JobSpecification spec, IStorageManagerInterface storageManager,
-            IBTreeRegistryProvider btreeRegistryProvider, IFileSplitProvider fileSplitProvider) {
+    public TreeIndexDropOperatorDescriptor(JobSpecification spec, IStorageManagerInterface storageManager,
+            IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider, IFileSplitProvider fileSplitProvider) {
         super(spec, 0, 0);
         this.storageManager = storageManager;
-        this.btreeRegistryProvider = btreeRegistryProvider;
+        this.treeIndexRegistryProvider = treeIndexRegistryProvider;
         this.fileSplitProvider = fileSplitProvider;
     }
 
     @Override
     public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
             IRecordDescriptorProvider recordDescProvider, int partition, int nPartitions) {
-        return new BTreeDropOperatorNodePushable(ctx, storageManager, btreeRegistryProvider, fileSplitProvider, partition);
+        return new TreeIndexDropOperatorNodePushable(ctx, storageManager, treeIndexRegistryProvider, fileSplitProvider,
+                partition);
     }
 }
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDropOperatorNodePushable.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDropOperatorNodePushable.java
new file mode 100644
index 0000000..71346f7
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDropOperatorNodePushable.java
@@ -0,0 +1,108 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import edu.uci.ics.hyracks.api.comm.IFrameWriter;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractOperatorNodePushable;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+
+public class TreeIndexDropOperatorNodePushable extends AbstractOperatorNodePushable {
+    private static final Logger LOGGER = Logger.getLogger(TreeIndexDropOperatorNodePushable.class.getName());
+
+    private final IHyracksStageletContext ctx;
+    private IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider;
+    private IStorageManagerInterface storageManager;
+    private IFileSplitProvider fileSplitProvider;
+    private int partition;
+
+    public TreeIndexDropOperatorNodePushable(IHyracksStageletContext ctx, IStorageManagerInterface storageManager,
+            IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider, IFileSplitProvider fileSplitProvider,
+            int partition) {
+        this.ctx = ctx;
+        this.storageManager = storageManager;
+        this.treeIndexRegistryProvider = treeIndexRegistryProvider;
+        this.fileSplitProvider = fileSplitProvider;
+        this.partition = partition;
+    }
+
+    @Override
+    public void deinitialize() throws HyracksDataException {
+    }
+
+    @Override
+    public int getInputArity() {
+        return 0;
+    }
+
+    @Override
+    public IFrameWriter getInputFrameWriter(int index) {
+        return null;
+    }
+
+    @Override
+    public void initialize() throws HyracksDataException {
+        try {
+
+            IndexRegistry<ITreeIndex> treeIndexRegistry = treeIndexRegistryProvider.getRegistry(ctx);
+            IBufferCache bufferCache = storageManager.getBufferCache(ctx);
+            IFileMapProvider fileMapProvider = storageManager.getFileMapProvider(ctx);
+
+            FileReference f = fileSplitProvider.getFileSplits()[partition].getLocalFile();
+
+            boolean fileIsMapped = fileMapProvider.isMapped(f);
+            if (!fileIsMapped) {
+                throw new HyracksDataException("Cannot drop Tree with name " + f.toString()
+                        + ". No file mapping exists.");
+            }
+
+            int indexFileId = fileMapProvider.lookupFileId(f);
+
+            // unregister tree instance
+            treeIndexRegistry.lock();
+            try {
+                treeIndexRegistry.unregister(indexFileId);
+            } finally {
+                treeIndexRegistry.unlock();
+            }
+
+            // remove name to id mapping
+            bufferCache.deleteFile(indexFileId);
+        }
+        // TODO: for the time being we don't throw,
+        // with proper exception handling (no hanging job problem) we should
+        // throw
+        catch (Exception e) {
+            if (LOGGER.isLoggable(Level.WARNING)) {
+                LOGGER.warning("Tree Drop Operator Failed Due To Exception: " + e.getMessage());
+            }
+        }
+    }
+
+    @Override
+    public void setOutputFrameWriter(int index, IFrameWriter writer, RecordDescriptor recordDesc) {
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexFileEnlistmentOperatorDescriptor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexFileEnlistmentOperatorDescriptor.java
new file mode 100644
index 0000000..0961a4f
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexFileEnlistmentOperatorDescriptor.java
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
+import edu.uci.ics.hyracks.api.job.JobSpecification;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+
+// re-create in-memory state for a tree index that has already been built (i.e., the file exists):
+// 1. register files in file manager (FileManager)
+// 2. create file mappings (FileMappingProvider)
+// 3. register tree index instance (IndexRegistry)
+
+public class TreeIndexFileEnlistmentOperatorDescriptor extends AbstractTreeIndexOperatorDescriptor {
+
+    private static final long serialVersionUID = 1L;
+
+    public TreeIndexFileEnlistmentOperatorDescriptor(JobSpecification spec, RecordDescriptor recDesc,
+            IStorageManagerInterface storageManager, IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider,
+            IFileSplitProvider fileSplitProvider, ITreeIndexFrameFactory interiorFrameFactory,
+            ITreeIndexFrameFactory leafFrameFactory, ITypeTrait[] typeTraits,
+            IBinaryComparatorFactory[] comparatorFactories, ITreeIndexOpHelperFactory opHelperFactory) {
+        super(spec, 0, 0, recDesc, storageManager, treeIndexRegistryProvider, fileSplitProvider, interiorFrameFactory,
+                leafFrameFactory, typeTraits, comparatorFactories, opHelperFactory);
+    }
+
+    @Override
+    public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
+            IRecordDescriptorProvider recordDescProvider, int partition, int partitions) throws HyracksDataException {
+        return new TreeIndexFileEnlistmentOperatorNodePushable(this, ctx, partition);
+    }
+
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeFileEnlistmentOperatorNodePushable.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexFileEnlistmentOperatorNodePushable.java
similarity index 69%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeFileEnlistmentOperatorNodePushable.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexFileEnlistmentOperatorNodePushable.java
index 023cd40..8ff6586 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeFileEnlistmentOperatorNodePushable.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexFileEnlistmentOperatorNodePushable.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
 
 import edu.uci.ics.hyracks.api.comm.IFrameWriter;
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
@@ -21,13 +21,14 @@
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.std.base.AbstractOperatorNodePushable;
 
-public class BTreeFileEnlistmentOperatorNodePushable extends AbstractOperatorNodePushable {
+public class TreeIndexFileEnlistmentOperatorNodePushable extends AbstractOperatorNodePushable {
 
-    private final BTreeOpHelper btreeOpHelper;
+    private final TreeIndexOpHelper treeIndexOpHelper;
 
-    public BTreeFileEnlistmentOperatorNodePushable(AbstractBTreeOperatorDescriptor opDesc, IHyracksStageletContext ctx,
-            int partition) {
-        btreeOpHelper = new BTreeOpHelper(opDesc, ctx, partition, BTreeOpHelper.BTreeMode.ENLIST_BTREE);
+    public TreeIndexFileEnlistmentOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc,
+            IHyracksStageletContext ctx, int partition) {
+        treeIndexOpHelper = opDesc.getTreeIndexOpHelperFactory().createTreeIndexOpHelper(opDesc, ctx, partition,
+                IndexHelperOpenMode.ENLIST);
     }
 
     @Override
@@ -47,10 +48,9 @@
     @Override
     public void initialize() throws HyracksDataException {
         try {
-        	btreeOpHelper.init();
-        }
-        finally {
-        	btreeOpHelper.deinit();
+            treeIndexOpHelper.init();
+        } finally {
+            treeIndexOpHelper.deinit();
         }
     }
 
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeInsertUpdateDeleteOperatorDescriptor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorDescriptor.java
similarity index 60%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeInsertUpdateDeleteOperatorDescriptor.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorDescriptor.java
index 7d50fff..c8141b9 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeInsertUpdateDeleteOperatorDescriptor.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorDescriptor.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.dataflow;
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
 
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
 import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
@@ -24,26 +24,27 @@
 import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
 import edu.uci.ics.hyracks.api.job.JobSpecification;
 import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
 import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
 
-public class BTreeInsertUpdateDeleteOperatorDescriptor extends AbstractBTreeOperatorDescriptor {
+public class TreeIndexInsertUpdateDeleteOperatorDescriptor extends AbstractTreeIndexOperatorDescriptor {
 
     private static final long serialVersionUID = 1L;
 
     private final int[] fieldPermutation;
 
-    private BTreeOp op;
+    private IndexOp op;
 
-    public BTreeInsertUpdateDeleteOperatorDescriptor(JobSpecification spec, RecordDescriptor recDesc,
-            IStorageManagerInterface storageManager, IBTreeRegistryProvider btreeRegistryProvider,
-            IFileSplitProvider fileSplitProvider, IBTreeInteriorFrameFactory interiorFactory,
-            IBTreeLeafFrameFactory leafFactory, ITypeTrait[] typeTraits,
-            IBinaryComparatorFactory[] comparatorFactories, int[] fieldPermutation, BTreeOp op) {
-        super(spec, 1, 1, recDesc, storageManager, btreeRegistryProvider, fileSplitProvider, interiorFactory,
-                leafFactory, typeTraits, comparatorFactories);
+    public TreeIndexInsertUpdateDeleteOperatorDescriptor(JobSpecification spec, RecordDescriptor recDesc,
+            IStorageManagerInterface storageManager, IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider,
+            IFileSplitProvider fileSplitProvider, ITreeIndexFrameFactory interiorFrameFactory,
+            ITreeIndexFrameFactory leafFrameFactory, ITypeTrait[] typeTraits,
+            IBinaryComparatorFactory[] comparatorFactories, int[] fieldPermutation, IndexOp op,
+            ITreeIndexOpHelperFactory opHelperFactory) {
+        super(spec, 1, 1, recDesc, storageManager, treeIndexRegistryProvider, fileSplitProvider, interiorFrameFactory,
+                leafFrameFactory, typeTraits, comparatorFactories, opHelperFactory);
         this.fieldPermutation = fieldPermutation;
         this.op = op;
     }
@@ -51,7 +52,7 @@
     @Override
     public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
             IRecordDescriptorProvider recordDescProvider, int partition, int nPartitions) {
-        return new BTreeInsertUpdateDeleteOperatorNodePushable(this, ctx, partition, fieldPermutation,
+        return new TreeIndexInsertUpdateDeleteOperatorNodePushable(this, ctx, partition, fieldPermutation,
                 recordDescProvider, op);
     }
 }
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorNodePushable.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorNodePushable.java
new file mode 100644
index 0000000..74a9efc
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexInsertUpdateDeleteOperatorNodePushable.java
@@ -0,0 +1,119 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputUnaryOutputOperatorNodePushable;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOpContext;
+
+public class TreeIndexInsertUpdateDeleteOperatorNodePushable extends AbstractUnaryInputUnaryOutputOperatorNodePushable {
+    private final TreeIndexOpHelper treeIndexOpHelper;
+    private FrameTupleAccessor accessor;
+    private final IRecordDescriptorProvider recordDescProvider;
+    private final IndexOp op;
+    private final PermutingFrameTupleReference tuple = new PermutingFrameTupleReference();
+    private ByteBuffer writeBuffer;
+    private IndexOpContext opCtx;
+
+    public TreeIndexInsertUpdateDeleteOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc,
+            IHyracksStageletContext ctx, int partition, int[] fieldPermutation,
+            IRecordDescriptorProvider recordDescProvider, IndexOp op) {
+        treeIndexOpHelper = opDesc.getTreeIndexOpHelperFactory().createTreeIndexOpHelper(opDesc, ctx, partition,
+                IndexHelperOpenMode.OPEN);
+        this.recordDescProvider = recordDescProvider;
+        this.op = op;
+        tuple.setFieldPermutation(fieldPermutation);
+    }
+
+    @Override
+    public void open() throws HyracksDataException {
+        AbstractTreeIndexOperatorDescriptor opDesc = (AbstractTreeIndexOperatorDescriptor) treeIndexOpHelper
+                .getOperatorDescriptor();
+        RecordDescriptor inputRecDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getOperatorId(), 0);
+        accessor = new FrameTupleAccessor(treeIndexOpHelper.getHyracksStageletContext().getFrameSize(), inputRecDesc);
+        writeBuffer = treeIndexOpHelper.getHyracksStageletContext().allocateFrame();
+        try {
+            treeIndexOpHelper.init();
+            treeIndexOpHelper.getTreeIndex().open(treeIndexOpHelper.getIndexFileId());
+            opCtx = treeIndexOpHelper.getTreeIndex().createOpContext(op, treeIndexOpHelper.getLeafFrame(),
+                    treeIndexOpHelper.getInteriorFrame(), new LIFOMetaDataFrame());
+        } catch (Exception e) {
+            // cleanup in case of failure
+            treeIndexOpHelper.deinit();
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
+        final ITreeIndex treeIndex = treeIndexOpHelper.getTreeIndex();
+        accessor.reset(buffer);
+
+        int tupleCount = accessor.getTupleCount();
+        for (int i = 0; i < tupleCount; i++) {
+            tuple.reset(accessor, i);
+            try {
+                switch (op) {
+
+                    case INSERT: {
+                        treeIndex.insert(tuple, opCtx);
+                    }
+                        break;
+
+                    case DELETE: {
+                        treeIndex.delete(tuple, opCtx);
+                    }
+                        break;
+
+                    default: {
+                        throw new HyracksDataException("Unsupported operation " + op
+                                + " in tree index InsertUpdateDelete operator");
+                    }
+
+                }
+
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+
+        // pass a copy of the frame to next op
+        System.arraycopy(buffer.array(), 0, writeBuffer.array(), 0, buffer.capacity());
+        FrameUtils.flushFrame(writeBuffer, writer);
+    }
+
+    @Override
+    public void close() throws HyracksDataException {
+        try {
+            writer.close();
+        } finally {
+            treeIndexOpHelper.deinit();
+        }
+    }
+
+    @Override
+    public void flush() throws HyracksDataException {
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexOpHelper.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexOpHelper.java
new file mode 100644
index 0000000..fca6d8d
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexOpHelper.java
@@ -0,0 +1,176 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.impls.TreeDiskOrderScanCursor;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+
+public abstract class TreeIndexOpHelper {
+
+    protected ITreeIndexFrame interiorFrame;
+    protected ITreeIndexFrame leafFrame;
+    protected MultiComparator cmp;
+
+    protected ITreeIndex treeIndex;
+    protected int indexFileId = -1;
+    protected int partition;
+
+    protected ITreeIndexOperatorDescriptorHelper opDesc;
+    protected IHyracksStageletContext ctx;
+
+    protected IndexHelperOpenMode mode;
+
+    public TreeIndexOpHelper(ITreeIndexOperatorDescriptorHelper opDesc, final IHyracksStageletContext ctx,
+            int partition, IndexHelperOpenMode mode) {
+        this.opDesc = opDesc;
+        this.ctx = ctx;
+        this.mode = mode;
+        this.partition = partition;
+    }
+
+    public void init() throws HyracksDataException {
+        IBufferCache bufferCache = opDesc.getStorageManager().getBufferCache(ctx);
+        IFileMapProvider fileMapProvider = opDesc.getStorageManager().getFileMapProvider(ctx);
+        IFileSplitProvider fileSplitProvider = opDesc.getTreeIndexFileSplitProvider();
+
+        FileReference f = fileSplitProvider.getFileSplits()[partition].getLocalFile();
+        boolean fileIsMapped = fileMapProvider.isMapped(f);
+
+        switch (mode) {
+
+            case OPEN: {
+                if (!fileIsMapped) {
+                    throw new HyracksDataException("Trying to open tree index from unmapped file " + f.toString());
+                }
+            }
+                break;
+
+            case CREATE:
+            case ENLIST: {
+                if (!fileIsMapped) {
+                    bufferCache.createFile(f);
+                }
+            }
+                break;
+
+        }
+
+        int fileId = fileMapProvider.lookupFileId(f);
+        try {
+            bufferCache.openFile(fileId);
+        } catch (HyracksDataException e) {
+            // revert state of buffer cache since file failed to open
+            if (!fileIsMapped) {
+                bufferCache.deleteFile(fileId);
+            }
+            throw e;
+        }
+
+        // only set indexFileId member when openFile() succeeds,
+        // otherwise deinit() will try to close the file that failed to open
+        indexFileId = fileId;
+
+        interiorFrame = opDesc.getTreeIndexInteriorFactory().createFrame();
+        leafFrame = opDesc.getTreeIndexLeafFactory().createFrame();
+
+        IndexRegistry<ITreeIndex> treeIndexRegistry = opDesc.getTreeIndexRegistryProvider().getRegistry(ctx);
+        treeIndex = treeIndexRegistry.get(indexFileId);
+        if (treeIndex == null) {
+
+            // create new tree and register it
+            treeIndexRegistry.lock();
+            try {
+                // check if tree has already been registered by another thread
+                treeIndex = treeIndexRegistry.get(indexFileId);
+                if (treeIndex == null) {
+                    // this thread should create and register the tree
+
+                    IBinaryComparator[] comparators = new IBinaryComparator[opDesc.getTreeIndexComparatorFactories().length];
+                    for (int i = 0; i < opDesc.getTreeIndexComparatorFactories().length; i++) {
+                        comparators[i] = opDesc.getTreeIndexComparatorFactories()[i].createBinaryComparator();
+                    }
+
+                    cmp = new MultiComparator(opDesc.getTreeIndexTypeTraits(), comparators);
+
+                    treeIndex = createTreeIndex();
+                    if (mode == IndexHelperOpenMode.CREATE) {
+                        ITreeIndexMetaDataFrame metaFrame = treeIndex.getFreePageManager().getMetaDataFrameFactory()
+                                .createFrame();
+                        try {
+                            treeIndex.create(indexFileId, leafFrame, metaFrame);
+                        } catch (Exception e) {
+                            throw new HyracksDataException(e);
+                        }
+                    }
+                    treeIndex.open(indexFileId);
+                    treeIndexRegistry.register(indexFileId, treeIndex);
+                }
+            } finally {
+                treeIndexRegistry.unlock();
+            }
+        }
+    }
+
+    // MUST be overridden
+    public ITreeIndex createTreeIndex() throws HyracksDataException {
+        throw new HyracksDataException("createTreeIndex Operation not implemented.");
+    }
+
+    public ITreeIndexCursor createDiskOrderScanCursor(ITreeIndexFrame leafFrame) throws HyracksDataException {
+        return new TreeDiskOrderScanCursor(leafFrame);
+    }
+
+    public void deinit() throws HyracksDataException {
+        if (indexFileId != -1) {
+            IBufferCache bufferCache = opDesc.getStorageManager().getBufferCache(ctx);
+            bufferCache.closeFile(indexFileId);
+        }
+    }
+
+    public ITreeIndex getTreeIndex() {
+        return treeIndex;
+    }
+
+    public IHyracksStageletContext getHyracksStageletContext() {
+        return ctx;
+    }
+
+    public ITreeIndexOperatorDescriptorHelper getOperatorDescriptor() {
+        return opDesc;
+    }
+
+    public ITreeIndexFrame getLeafFrame() {
+        return leafFrame;
+    }
+
+    public ITreeIndexFrame getInteriorFrame() {
+        return interiorFrame;
+    }
+
+    public int getIndexFileId() {
+        return indexFileId;
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexStatsOperatorDescriptor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexStatsOperatorDescriptor.java
new file mode 100644
index 0000000..574e727
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexStatsOperatorDescriptor.java
@@ -0,0 +1,33 @@
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
+import edu.uci.ics.hyracks.api.job.JobSpecification;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+
+public class TreeIndexStatsOperatorDescriptor extends AbstractTreeIndexOperatorDescriptor {
+
+    private static final long serialVersionUID = 1L;
+
+    public TreeIndexStatsOperatorDescriptor(JobSpecification spec, IStorageManagerInterface storageManager,
+            IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider, IFileSplitProvider fileSplitProvider,
+            ITreeIndexFrameFactory interiorFrameFactory, ITreeIndexFrameFactory leafFrameFactory,
+            ITypeTrait[] typeTraits, IBinaryComparatorFactory[] comparatorFactories,
+            ITreeIndexOpHelperFactory opHelperFactory) {
+        super(spec, 0, 0, null, storageManager, treeIndexRegistryProvider, fileSplitProvider, interiorFrameFactory,
+                leafFrameFactory, typeTraits, comparatorFactories, opHelperFactory);
+    }
+
+    @Override
+    public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
+            IRecordDescriptorProvider recordDescProvider, int partition, int nPartitions) {
+        return new TreeIndexStatsOperatorNodePushable(this, ctx, partition);
+    }
+}
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexStatsOperatorNodePushable.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexStatsOperatorNodePushable.java
new file mode 100644
index 0000000..f47855f
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexStatsOperatorNodePushable.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.storage.am.common.dataflow;
+
+import edu.uci.ics.hyracks.api.comm.IFrameWriter;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractOperatorNodePushable;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.utility.TreeIndexStats;
+import edu.uci.ics.hyracks.storage.am.common.utility.TreeIndexStatsGatherer;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+
+public class TreeIndexStatsOperatorNodePushable extends AbstractOperatorNodePushable {
+    private final TreeIndexOpHelper treeIndexOpHelper;
+    private final IHyracksStageletContext ctx;
+    private TreeIndexStatsGatherer statsGatherer;
+
+    public TreeIndexStatsOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc, IHyracksStageletContext ctx,
+            int partition) {
+        treeIndexOpHelper = opDesc.getTreeIndexOpHelperFactory().createTreeIndexOpHelper(opDesc, ctx, partition,
+                IndexHelperOpenMode.CREATE);
+        this.ctx = ctx;
+    }
+
+    @Override
+    public void deinitialize() throws HyracksDataException {
+    }
+
+    @Override
+    public int getInputArity() {
+        return 0;
+    }
+
+    @Override
+    public IFrameWriter getInputFrameWriter(int index) {
+        return null;
+    }
+
+    @Override
+    public void initialize() throws HyracksDataException {
+        try {
+            treeIndexOpHelper.init();
+            treeIndexOpHelper.getTreeIndex().open(treeIndexOpHelper.getIndexFileId());
+
+            ITreeIndex treeIndex = treeIndexOpHelper.getTreeIndex();
+            IBufferCache bufferCache = treeIndexOpHelper.getOperatorDescriptor().getStorageManager()
+                    .getBufferCache(ctx);
+
+            statsGatherer = new TreeIndexStatsGatherer(bufferCache, treeIndex.getFreePageManager(),
+                    treeIndexOpHelper.getIndexFileId(), treeIndex.getRootPageId());
+            TreeIndexStats stats = statsGatherer.gatherStats(treeIndex.getLeafFrameFactory().createFrame(), treeIndex
+                    .getInteriorFrameFactory().createFrame(), treeIndex.getFreePageManager().getMetaDataFrameFactory()
+                    .createFrame());
+            System.err.println(stats.toString());
+        } catch (Exception e) {
+            treeIndexOpHelper.deinit();
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void setOutputFrameWriter(int index, IFrameWriter writer, RecordDescriptor recordDesc) {
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/AbstractSlotManager.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/AbstractSlotManager.java
new file mode 100644
index 0000000..87fea47
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/AbstractSlotManager.java
@@ -0,0 +1,60 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.common.frames;
+
+import edu.uci.ics.hyracks.storage.am.common.api.ISlotManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+
+public abstract class AbstractSlotManager implements ISlotManager {
+
+    protected static final int slotSize = 4;
+    protected ITreeIndexFrame frame;
+
+    @Override
+    public int getTupleOff(int offset) {
+        return frame.getBuffer().getInt(offset);
+    }
+
+    @Override
+    public void setSlot(int offset, int value) {
+        frame.getBuffer().putInt(offset, value);
+    }
+
+    @Override
+    public int getSlotEndOff() {
+        return frame.getBuffer().capacity() - (frame.getTupleCount() * slotSize);
+    }
+
+    @Override
+    public int getSlotStartOff() {
+        return frame.getBuffer().capacity() - slotSize;
+    }
+
+    @Override
+    public int getSlotSize() {
+        return slotSize;
+    }
+
+    @Override
+    public void setFrame(ITreeIndexFrame frame) {
+        this.frame = frame;
+    }
+
+    @Override
+    public int getSlotOff(int tupleIndex) {
+        return getSlotStartOff() - tupleIndex * slotSize;
+    }
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/SpaceStatus.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/FrameOpSpaceStatus.java
similarity index 88%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/SpaceStatus.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/FrameOpSpaceStatus.java
index 9ad15ee..97a4730 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/SpaceStatus.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/FrameOpSpaceStatus.java
@@ -13,8 +13,8 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.common.frames;
 
-public enum SpaceStatus {
+public enum FrameOpSpaceStatus {
     INSUFFICIENT_SPACE, SUFFICIENT_CONTIGUOUS_SPACE, SUFFICIENT_SPACE
 }
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/MetaDataFrame.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/LIFOMetaDataFrame.java
similarity index 89%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/MetaDataFrame.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/LIFOMetaDataFrame.java
index a219dd6..b621b89 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/MetaDataFrame.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/LIFOMetaDataFrame.java
@@ -13,11 +13,11 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.frames;
+package edu.uci.ics.hyracks.storage.am.common.frames;
 
 import java.nio.ByteBuffer;
 
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 
 // all meta pages of this kind have a negative level
@@ -25,13 +25,14 @@
 // the first meta page is special because it guarantees to have a correct max page
 // other meta pages (i.e., with level -2) have junk in the max page field
 
-public class MetaDataFrame implements IBTreeMetaDataFrame {
+public class LIFOMetaDataFrame implements ITreeIndexMetaDataFrame {
 
     protected static final int tupleCountOff = 0;
     protected static final int freeSpaceOff = tupleCountOff + 4;
     protected static final int maxPageOff = freeSpaceOff + 4;
-    protected static final byte levelOff = maxPageOff + 1;
-    protected static final byte nextPageOff = maxPageOff + 8;
+    protected static final int dummyFieldOff = maxPageOff + 4;
+    protected static final byte levelOff = dummyFieldOff + 4;
+    protected static final byte nextPageOff = levelOff + 1;
 
     protected ICachedPage page = null;
     protected ByteBuffer buf = null;
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/MetaDataFrameFactory.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/LIFOMetaDataFrameFactory.java
similarity index 63%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/MetaDataFrameFactory.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/LIFOMetaDataFrameFactory.java
index 9896bf9..409c8b2 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/MetaDataFrameFactory.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/LIFOMetaDataFrameFactory.java
@@ -13,14 +13,14 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.frames;
+package edu.uci.ics.hyracks.storage.am.common.frames;
 
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
 
-public class MetaDataFrameFactory implements IBTreeMetaDataFrameFactory {
+public class LIFOMetaDataFrameFactory implements ITreeIndexMetaDataFrameFactory {
     @Override
-    public IBTreeMetaDataFrame getFrame() {
-        return new MetaDataFrame();
+    public ITreeIndexMetaDataFrame createFrame() {
+        return new LIFOMetaDataFrame();
     }
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMFrame.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/TreeIndexNSMFrame.java
similarity index 76%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMFrame.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/TreeIndexNSMFrame.java
index 2324eab..af1e337 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/frames/NSMFrame.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/frames/TreeIndexNSMFrame.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.frames;
+package edu.uci.ics.hyracks.storage.am.common.frames;
 
 import java.io.ByteArrayInputStream;
 import java.io.DataInput;
@@ -25,20 +25,18 @@
 import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
-import edu.uci.ics.hyracks.storage.am.btree.api.ISlotManager;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeException;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleMode;
-import edu.uci.ics.hyracks.storage.am.btree.impls.FindTupleNoExactMatchPolicy;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
-import edu.uci.ics.hyracks.storage.am.btree.impls.OrderedSlotManager;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SlotOffTupleOff;
-import edu.uci.ics.hyracks.storage.am.btree.impls.SpaceStatus;
+import edu.uci.ics.hyracks.storage.am.common.api.ISlotManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.SlotOffTupleOff;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 
-public abstract class NSMFrame implements IBTreeFrame {
+public abstract class TreeIndexNSMFrame implements ITreeIndexFrame {
 
     protected static final int pageLsnOff = 0; // 0
     protected static final int tupleCountOff = pageLsnOff + 4; // 4
@@ -51,13 +49,13 @@
     protected ByteBuffer buf = null;
     protected ISlotManager slotManager;
 
-    protected IBTreeTupleWriter tupleWriter;
-    protected IBTreeTupleReference frameTuple;
+    protected ITreeIndexTupleWriter tupleWriter;
+    protected ITreeIndexTupleReference frameTuple;
 
-    public NSMFrame(IBTreeTupleWriter tupleWriter) {
+    public TreeIndexNSMFrame(ITreeIndexTupleWriter tupleWriter, ISlotManager slotManager) {
         this.tupleWriter = tupleWriter;
         this.frameTuple = tupleWriter.createTupleReference();
-        this.slotManager = new OrderedSlotManager();
+        this.slotManager = slotManager;
     }
 
     @Override
@@ -76,6 +74,11 @@
     }
 
     @Override
+    public boolean isInterior() {
+        return buf.get(levelOff) > 0;
+    }
+
+    @Override
     public byte getLevel() {
         return buf.get(levelOff);
     }
@@ -126,7 +129,7 @@
     }
 
     @Override
-    public void compact(MultiComparator cmp) {
+    public boolean compact(MultiComparator cmp) {
         resetSpaceParams();
         frameTuple.setFieldCount(cmp.getFieldCount());
 
@@ -144,7 +147,7 @@
 
         for (int i = 0; i < sortedTupleOffs.size(); i++) {
             int tupleOff = sortedTupleOffs.get(i).tupleOff;
-            frameTuple.resetByOffset(buf, tupleOff);
+            frameTuple.resetByTupleOffset(buf, tupleOff);
 
             int tupleEndOff = frameTuple.getFieldStart(frameTuple.getFieldCount() - 1)
                     + frameTuple.getFieldLength(frameTuple.getFieldCount() - 1);
@@ -157,33 +160,36 @@
 
         buf.putInt(freeSpaceOff, freeSpace);
         buf.putInt(totalFreeSpaceOff, buf.capacity() - freeSpace - tupleCount * slotManager.getSlotSize());
+
+        return false;
     }
 
     @Override
     public void delete(ITupleReference tuple, MultiComparator cmp, boolean exactDelete) throws Exception {
+
         frameTuple.setFieldCount(cmp.getFieldCount());
         int tupleIndex = slotManager.findTupleIndex(tuple, frameTuple, cmp, FindTupleMode.FTM_EXACT,
                 FindTupleNoExactMatchPolicy.FTP_HIGHER_KEY);
         int slotOff = slotManager.getSlotOff(tupleIndex);
         if (tupleIndex < 0) {
-            throw new BTreeException("Key to be deleted does not exist.");
+            throw new TreeIndexException("Key to be deleted does not exist.");
         } else {
             if (exactDelete) {
                 // check the non-key columns for equality by byte-by-byte
                 // comparison
                 int tupleOff = slotManager.getTupleOff(slotOff);
-                frameTuple.resetByOffset(buf, tupleOff);
+                frameTuple.resetByTupleOffset(buf, tupleOff);
 
-                int comparison = cmp.fieldRangeCompare(tuple, frameTuple, cmp.getKeyFieldCount() - 1, cmp
-                        .getFieldCount()
-                        - cmp.getKeyFieldCount());
+                int comparison = cmp.fieldRangeCompare(tuple, frameTuple, cmp.getKeyFieldCount() - 1,
+                        cmp.getFieldCount() - cmp.getKeyFieldCount());
                 if (comparison != 0) {
-                    throw new BTreeException("Cannot delete tuple. Byte-by-byte comparison failed to prove equality.");
+                    throw new TreeIndexException(
+                            "Cannot delete tuple. Byte-by-byte comparison failed to prove equality.");
                 }
             }
 
             int tupleOff = slotManager.getTupleOff(slotOff);
-            frameTuple.resetByOffset(buf, tupleOff);
+            frameTuple.resetByTupleOffset(buf, tupleOff);
             int tupleSize = tupleWriter.bytesRequired(frameTuple);
 
             // perform deletion (we just do a memcpy to overwrite the slot)
@@ -198,36 +204,39 @@
     }
 
     @Override
-    public SpaceStatus hasSpaceInsert(ITupleReference tuple, MultiComparator cmp) {
+    public FrameOpSpaceStatus hasSpaceInsert(ITupleReference tuple, MultiComparator cmp) {
         int bytesRequired = tupleWriter.bytesRequired(tuple);
         if (bytesRequired + slotManager.getSlotSize() <= buf.capacity() - buf.getInt(freeSpaceOff)
                 - (buf.getInt(tupleCountOff) * slotManager.getSlotSize()))
-            return SpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE;
+            return FrameOpSpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE;
         else if (bytesRequired + slotManager.getSlotSize() <= buf.getInt(totalFreeSpaceOff))
-            return SpaceStatus.SUFFICIENT_SPACE;
+            return FrameOpSpaceStatus.SUFFICIENT_SPACE;
         else
-            return SpaceStatus.INSUFFICIENT_SPACE;
+            return FrameOpSpaceStatus.INSUFFICIENT_SPACE;
     }
 
     @Override
-    public SpaceStatus hasSpaceUpdate(int rid, ITupleReference tuple, MultiComparator cmp) {
+    public FrameOpSpaceStatus hasSpaceUpdate(int rid, ITupleReference tuple, MultiComparator cmp) {
         // TODO Auto-generated method stub
-        return SpaceStatus.INSUFFICIENT_SPACE;
+        return FrameOpSpaceStatus.INSUFFICIENT_SPACE;
     }
 
     protected void resetSpaceParams() {
-        buf.putInt(freeSpaceOff, totalFreeSpaceOff + 4);
-        buf.putInt(totalFreeSpaceOff, buf.capacity() - (totalFreeSpaceOff + 4));
+        buf.putInt(freeSpaceOff, smFlagOff + 1);
+        buf.putInt(totalFreeSpaceOff, buf.capacity() - (smFlagOff + 1));
     }
 
     @Override
-    public void insert(ITupleReference tuple, MultiComparator cmp) throws Exception {
+    public int findTupleIndex(ITupleReference tuple, MultiComparator cmp) throws Exception {
         frameTuple.setFieldCount(cmp.getFieldCount());
-        int tupleIndex = slotManager.findTupleIndex(tuple, frameTuple, cmp, FindTupleMode.FTM_INCLUSIVE,
+        return slotManager.findTupleIndex(tuple, frameTuple, cmp, FindTupleMode.FTM_INCLUSIVE,
                 FindTupleNoExactMatchPolicy.FTP_HIGHER_KEY);
+    }
+
+    @Override
+    public void insert(ITupleReference tuple, MultiComparator cmp, int tupleIndex) throws Exception {
         slotManager.insertSlot(tupleIndex, buf.getInt(freeSpaceOff));
         int bytesWritten = tupleWriter.writeTuple(tuple, buf, buf.getInt(freeSpaceOff));
-
         buf.putInt(tupleCountOff, buf.getInt(tupleCountOff) + 1);
         buf.putInt(freeSpaceOff, buf.getInt(freeSpaceOff) + bytesWritten);
         buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) - bytesWritten - slotManager.getSlotSize());
@@ -262,8 +271,8 @@
         for (int i = 0; i < tupleCount; i++) {
             frameTuple.resetByTupleIndex(this, i);
             for (int j = 0; j < cmp.getKeyFieldCount(); j++) {
-                ByteArrayInputStream inStream = new ByteArrayInputStream(frameTuple.getFieldData(j), frameTuple
-                        .getFieldStart(j), frameTuple.getFieldLength(j));
+                ByteArrayInputStream inStream = new ByteArrayInputStream(frameTuple.getFieldData(j),
+                        frameTuple.getFieldStart(j), frameTuple.getFieldLength(j));
                 DataInput dataIn = new DataInputStream(inStream);
                 Object o = fields[j].deserialize(dataIn);
                 strBuilder.append(o.toString() + " ");
@@ -309,7 +318,7 @@
         frameTuple.setFieldCount(fieldCount);
     }
 
-    public IBTreeTupleWriter getTupleWriter() {
+    public ITreeIndexTupleWriter getTupleWriter() {
         return tupleWriter;
     }
 }
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/freepage/LinkedListFreePageManager.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/freepage/LinkedListFreePageManager.java
new file mode 100644
index 0000000..42bf70f
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/freepage/LinkedListFreePageManager.java
@@ -0,0 +1,187 @@
+package edu.uci.ics.hyracks.storage.am.common.freepage;
+
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
+
+public class LinkedListFreePageManager implements IFreePageManager {
+
+    private static final byte META_PAGE_LEVEL_INDICATOR = -1;
+    private static final byte FREE_PAGE_LEVEL_INDICATOR = -2;
+    private final IBufferCache bufferCache;
+    private final int fileId;
+    private final int headPage;
+    private final ITreeIndexMetaDataFrameFactory metaDataFrameFactory;
+
+    public LinkedListFreePageManager(IBufferCache bufferCache, int fileId, int headPage,
+            ITreeIndexMetaDataFrameFactory metaDataFrameFactory) {
+        this.bufferCache = bufferCache;
+        this.fileId = fileId;
+        this.headPage = headPage;
+        this.metaDataFrameFactory = metaDataFrameFactory;
+    }
+
+    @Override
+    public void addFreePage(ITreeIndexMetaDataFrame metaFrame, int freePage) throws HyracksDataException {
+
+        ICachedPage metaNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, headPage), false);
+        metaNode.acquireWriteLatch();
+
+        try {
+            metaFrame.setPage(metaNode);
+
+            if (metaFrame.hasSpace()) {
+                metaFrame.addFreePage(freePage);
+            } else {
+                // allocate a new page in the chain of meta pages
+                int newPage = metaFrame.getFreePage();
+                if (newPage < 0) {
+                    throw new Exception("Inconsistent Meta Page State. It has no space, but it also has no entries.");
+                }
+
+                ICachedPage newNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, newPage), false);
+                newNode.acquireWriteLatch();
+
+                try {
+                    int metaMaxPage = metaFrame.getMaxPage();
+
+                    // copy metaDataPage to newNode
+                    System.arraycopy(metaNode.getBuffer().array(), 0, newNode.getBuffer().array(), 0, metaNode
+                            .getBuffer().capacity());
+
+                    metaFrame.initBuffer(META_PAGE_LEVEL_INDICATOR);
+                    metaFrame.setNextPage(newPage);
+                    metaFrame.setMaxPage(metaMaxPage);
+                    metaFrame.addFreePage(freePage);
+                } finally {
+                    newNode.releaseWriteLatch();
+                    bufferCache.unpin(newNode);
+                }
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            metaNode.releaseWriteLatch();
+            bufferCache.unpin(metaNode);
+        }
+    }
+
+    @Override
+    public int getFreePage(ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException {
+        ICachedPage metaNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, headPage), false);
+
+        metaNode.acquireWriteLatch();
+
+        int freePage = -1;
+        try {
+            metaFrame.setPage(metaNode);
+            freePage = metaFrame.getFreePage();
+            if (freePage < 0) { // no free page entry on this page
+                int nextPage = metaFrame.getNextPage();
+                if (nextPage > 0) { // sibling may have free pages
+                    ICachedPage nextNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, nextPage), false);
+
+                    nextNode.acquireWriteLatch();
+                    // we copy over the free space entries of nextpage into the
+                    // first meta page (metaDataPage)
+                    // we need to link the first page properly to the next page
+                    // of nextpage
+                    try {
+                        // remember entries that remain unchanged
+                        int maxPage = metaFrame.getMaxPage();
+
+                        // copy entire page (including sibling pointer, free
+                        // page entries, and all other info)
+                        // after this copy nextPage is considered a free page
+                        System.arraycopy(nextNode.getBuffer().array(), 0, metaNode.getBuffer().array(), 0, nextNode
+                                .getBuffer().capacity());
+
+                        // reset unchanged entry
+                        metaFrame.setMaxPage(maxPage);
+
+                        freePage = metaFrame.getFreePage();
+                        // sibling also has no free pages, this "should" not
+                        // happen, but we deal with it anyway just to be safe
+                        if (freePage < 0) {
+                            freePage = nextPage;
+                        } else {
+                            metaFrame.addFreePage(nextPage);
+                        }
+                    } finally {
+                        nextNode.releaseWriteLatch();
+                        bufferCache.unpin(nextNode);
+                    }
+                } else {
+                    freePage = metaFrame.getMaxPage();
+                    freePage++;
+                    metaFrame.setMaxPage(freePage);
+                }
+            }
+        } finally {
+            metaNode.releaseWriteLatch();
+            bufferCache.unpin(metaNode);
+        }
+
+        return freePage;
+    }
+
+    @Override
+    public int getMaxPage(ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException {
+        ICachedPage metaNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, headPage), false);
+        metaNode.acquireWriteLatch();
+        int maxPage = -1;
+        try {
+            metaFrame.setPage(metaNode);
+            maxPage = metaFrame.getMaxPage();
+        } finally {
+            metaNode.releaseWriteLatch();
+            bufferCache.unpin(metaNode);
+        }
+        return maxPage;
+    }
+
+    @Override
+    public void init(ITreeIndexMetaDataFrame metaFrame, int currentMaxPage) throws HyracksDataException {
+        // initialize meta data page
+        ICachedPage metaNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, headPage), true);
+
+        metaNode.acquireWriteLatch();
+        try {
+            metaFrame.setPage(metaNode);
+            metaFrame.initBuffer(META_PAGE_LEVEL_INDICATOR);
+            metaFrame.setMaxPage(currentMaxPage);
+        } finally {
+            metaNode.releaseWriteLatch();
+            bufferCache.unpin(metaNode);
+        }
+    }
+
+    @Override
+    public ITreeIndexMetaDataFrameFactory getMetaDataFrameFactory() {
+        return metaDataFrameFactory;
+    }
+
+    @Override
+    public byte getFreePageLevelIndicator() {
+        return FREE_PAGE_LEVEL_INDICATOR;
+    }
+
+    @Override
+    public byte getMetaPageLevelIndicator() {
+        return META_PAGE_LEVEL_INDICATOR;
+    }
+
+    @Override
+    public boolean isFreePage(ITreeIndexMetaDataFrame metaFrame) {
+        return metaFrame.getLevel() == FREE_PAGE_LEVEL_INDICATOR;
+    }
+
+    @Override
+    public boolean isMetaPage(ITreeIndexMetaDataFrame metaFrame) {
+        return metaFrame.getLevel() == META_PAGE_LEVEL_INDICATOR;
+    }
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/DiskOrderScanCursor.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/impls/TreeDiskOrderScanCursor.java
similarity index 73%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/DiskOrderScanCursor.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/impls/TreeDiskOrderScanCursor.java
index 29086ba..2c2cb5e 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/DiskOrderScanCursor.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/impls/TreeDiskOrderScanCursor.java
@@ -13,34 +13,32 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.common.impls;
 
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeCursor;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.ISearchPredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.ICursorInitialState;
+import edu.uci.ics.hyracks.storage.am.common.api.ISearchPredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
 
-public class DiskOrderScanCursor implements IBTreeCursor {
-
-    // TODO: might want to return tuples in physical order, not logical order to
-    // speed up access
+public class TreeDiskOrderScanCursor implements ITreeIndexCursor {
 
     private int tupleIndex = 0;
     private int fileId = -1;
     int currentPageId = -1;
-    int maxPageId = -1; // TODO: figure out how to scan to the end of file, this
-    // is dirty and may not with concurrent updates
+    int maxPageId = -1;
     private ICachedPage page = null;
-    private IBTreeLeafFrame frame = null;
+    private ITreeIndexFrame frame = null;
     private IBufferCache bufferCache = null;
 
-    private IBTreeTupleReference frameTuple;
+    private ITreeIndexTupleReference frameTuple;
 
-    public DiskOrderScanCursor(IBTreeLeafFrame frame) {
+    public TreeDiskOrderScanCursor(ITreeIndexFrame frame) {
         this.frame = frame;
         this.frameTuple = frame.getTupleWriter().createTupleReference();
     }
@@ -53,7 +51,7 @@
     }
 
     @Override
-    public IBTreeTupleReference getTuple() {
+    public ITreeIndexTupleReference getTuple() {
         return frameTuple;
     }
 
@@ -105,23 +103,22 @@
     }
 
     @Override
-    public void open(ICachedPage page, ISearchPredicate searchPred) throws HyracksDataException {
+    public void open(ICursorInitialState initialState, ISearchPredicate searchPred) throws HyracksDataException {
         // in case open is called multiple times without closing
-        if (this.page != null) {
-            this.page.releaseReadLatch();
-            bufferCache.unpin(this.page);
+        if (page != null) {
+            page.releaseReadLatch();
+            bufferCache.unpin(page);
         }
 
-        this.page = page;
+        page = initialState.getPage();
         tupleIndex = 0;
         frame.setPage(page);
-        RangePredicate pred = (RangePredicate) searchPred;
-        MultiComparator lowKeyCmp = pred.getLowKeyComparator();
+        MultiComparator lowKeyCmp = searchPred.getLowKeyComparator();
         frameTuple.setFieldCount(lowKeyCmp.getFieldCount());
         boolean leafExists = positionToNextLeaf(false);
         if (!leafExists) {
             throw new HyracksDataException(
-                    "Failed to open disk-order scan cursor for B-tree. Traget B-tree has no leaves.");
+                    "Failed to open disk-order scan cursor for tree index. Traget tree index has no leaves.");
         }
     }
 
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FindTupleMode.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/FindTupleMode.java
similarity index 92%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FindTupleMode.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/FindTupleMode.java
index 9e2fa75..cea2500 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FindTupleMode.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/FindTupleMode.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.common.ophelpers;
 
 public enum FindTupleMode {
     FTM_INCLUSIVE, FTM_EXCLUSIVE, FTM_EXACT
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FindTupleNoExactMatchPolicy.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/FindTupleNoExactMatchPolicy.java
similarity index 92%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FindTupleNoExactMatchPolicy.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/FindTupleNoExactMatchPolicy.java
index 1bc6ea3..0d534ed 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/FindTupleNoExactMatchPolicy.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/FindTupleNoExactMatchPolicy.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.common.ophelpers;
 
 public enum FindTupleNoExactMatchPolicy {
     FTP_LOWER_KEY, FTP_HIGHER_KEY
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOp.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/IndexOp.java
similarity index 82%
copy from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOp.java
copy to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/IndexOp.java
index d698c8a..e40c5c8 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOp.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/IndexOp.java
@@ -13,8 +13,8 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.common.ophelpers;
 
-public enum BTreeOp {
-    BTO_INSERT, BTO_DELETE, BTO_UPDATE, BTO_SEARCH
+public enum IndexOp {
+    INSERT, DELETE, UPDATE, SEARCH, DISKORDERSCAN
 }
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/IndexOpContext.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/IndexOpContext.java
new file mode 100644
index 0000000..4f6e656
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/IndexOpContext.java
@@ -0,0 +1,5 @@
+package edu.uci.ics.hyracks.storage.am.common.ophelpers;
+
+public interface IndexOpContext {
+    void reset();
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/IntArrayList.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/IntArrayList.java
similarity index 76%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/IntArrayList.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/IntArrayList.java
index 2d0b9df..46551dd 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/IntArrayList.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/IntArrayList.java
@@ -13,16 +13,18 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.common.ophelpers;
 
 public class IntArrayList {
     private int[] data;
     private int size;
+    private int first;
     private final int growth;
 
     public IntArrayList(int initialCapacity, int growth) {
         data = new int[initialCapacity];
         size = 0;
+        first = 0;
         this.growth = growth;
     }
 
@@ -30,6 +32,10 @@
         return size;
     }
 
+    public int first() {
+        return first;
+    }
+
     public void add(int i) {
         if (size == data.length) {
             int[] newData = new int[data.length + growth];
@@ -54,8 +60,27 @@
         return data[i];
     }
 
+    // WARNING: caller is responsible for checking i < size
+    public void set(int i, int value) {
+        data[i] = value;
+
+    }
+
+    public int getFirst() {
+        return data[first];
+    }
+
+    public void moveFirst() {
+        first++;
+    }
+
     public void clear() {
         size = 0;
+        first = 0;
+    }
+
+    public boolean isLast() {
+        return size == first;
     }
 
     public boolean isEmpty() {
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/MultiComparator.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/MultiComparator.java
similarity index 83%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/MultiComparator.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/MultiComparator.java
index e029af0..1842bf8 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/MultiComparator.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/MultiComparator.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.common.ophelpers;
 
 import java.io.ByteArrayInputStream;
 import java.io.DataInput;
@@ -24,8 +24,8 @@
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.IntegerBinaryComparatorFactory;
 
-@SuppressWarnings("unchecked")
 public class MultiComparator {
 
     private static final long serialVersionUID = 1L;
@@ -33,6 +33,12 @@
     private IBinaryComparator[] cmps = null;
     private ITypeTrait[] typeTraits;
 
+    private IBinaryComparator intCmp = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+
+    public IBinaryComparator getIntCmp() {
+        return intCmp;
+    }
+
     public MultiComparator(ITypeTrait[] typeTraits, IBinaryComparator[] cmps) {
         this.typeTraits = typeTraits;
         this.cmps = cmps;
@@ -40,8 +46,8 @@
 
     public int compare(ITupleReference tupleA, ITupleReference tupleB) {
         for (int i = 0; i < cmps.length; i++) {
-            int cmp = cmps[i].compare(tupleA.getFieldData(i), tupleA.getFieldStart(i), tupleA.getFieldLength(i), tupleB
-                    .getFieldData(i), tupleB.getFieldStart(i), tupleB.getFieldLength(i));
+            int cmp = cmps[i].compare(tupleA.getFieldData(i), tupleA.getFieldStart(i), tupleA.getFieldLength(i),
+                    tupleB.getFieldData(i), tupleB.getFieldStart(i), tupleB.getFieldLength(i));
             if (cmp < 0)
                 return -1;
             else if (cmp > 0)
@@ -52,8 +58,8 @@
 
     public int fieldRangeCompare(ITupleReference tupleA, ITupleReference tupleB, int startFieldIndex, int numFields) {
         for (int i = startFieldIndex; i < startFieldIndex + numFields; i++) {
-            int cmp = cmps[i].compare(tupleA.getFieldData(i), tupleA.getFieldStart(i), tupleA.getFieldLength(i), tupleB
-                    .getFieldData(i), tupleB.getFieldStart(i), tupleB.getFieldLength(i));
+            int cmp = cmps[i].compare(tupleA.getFieldData(i), tupleA.getFieldStart(i), tupleA.getFieldLength(i),
+                    tupleB.getFieldData(i), tupleB.getFieldStart(i), tupleB.getFieldLength(i));
             if (cmp < 0)
                 return -1;
             else if (cmp > 0)
@@ -86,10 +92,6 @@
         this.cmps = cmps;
     }
 
-    public int size() {
-        return cmps.length;
-    }
-
     public int getFieldCount() {
         return typeTraits.length;
     }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/SlotOffTupleOff.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/SlotOffTupleOff.java
similarity index 94%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/SlotOffTupleOff.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/SlotOffTupleOff.java
index c074642..4fc1861 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/SlotOffTupleOff.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/SlotOffTupleOff.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.common.ophelpers;
 
 public class SlotOffTupleOff implements Comparable<SlotOffTupleOff> {
     public int tupleIndex;
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleReference.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/SimpleTupleReference.java
similarity index 70%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleReference.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/SimpleTupleReference.java
index d2b2892..f9e00ac 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleReference.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/SimpleTupleReference.java
@@ -13,14 +13,14 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.tuples;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
 import java.nio.ByteBuffer;
 
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
 
-public class SimpleTupleReference implements IBTreeTupleReference {
+public class SimpleTupleReference implements ITreeIndexTupleReference {
 
     protected ByteBuffer buf;
     protected int fieldStartIndex;
@@ -30,14 +30,14 @@
     protected int fieldSlotsBytes;
 
     @Override
-    public void resetByOffset(ByteBuffer buf, int tupleStartOff) {
+    public void resetByTupleOffset(ByteBuffer buf, int tupleStartOff) {
         this.buf = buf;
         this.tupleStartOff = tupleStartOff;
     }
 
     @Override
-    public void resetByTupleIndex(IBTreeFrame frame, int tupleIndex) {
-        resetByOffset(frame.getBuffer(), frame.getTupleOffset(tupleIndex));
+    public void resetByTupleIndex(ITreeIndexFrame frame, int tupleIndex) {
+        resetByTupleOffset(frame.getBuffer(), frame.getTupleOffset(tupleIndex));
     }
 
     @Override
@@ -67,10 +67,10 @@
     @Override
     public int getFieldLength(int fIdx) {
         if (fIdx == 0) {
-            return buf.getInt(tupleStartOff + nullFlagsBytes);
+            return buf.getShort(tupleStartOff + nullFlagsBytes);
         } else {
-            return buf.getInt(tupleStartOff + nullFlagsBytes + fIdx * 4)
-                    - buf.getInt(tupleStartOff + nullFlagsBytes + ((fIdx - 1) * 4));
+            return buf.getShort(tupleStartOff + nullFlagsBytes + fIdx * 2)
+                    - buf.getShort(tupleStartOff + nullFlagsBytes + ((fIdx - 1) * 2));
         }
     }
 
@@ -80,7 +80,7 @@
             return tupleStartOff + nullFlagsBytes + fieldSlotsBytes;
         } else {
             return tupleStartOff + nullFlagsBytes + fieldSlotsBytes
-                    + buf.getInt(tupleStartOff + nullFlagsBytes + ((fIdx - 1) * 4));
+                    + buf.getShort(tupleStartOff + nullFlagsBytes + ((fIdx - 1) * 2));
         }
     }
 
@@ -89,6 +89,6 @@
     }
 
     protected int getFieldSlotsBytes() {
-        return fieldCount * 4;
+        return fieldCount * 2;
     }
-}
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleWriter.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/SimpleTupleWriter.java
similarity index 74%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleWriter.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/SimpleTupleWriter.java
index 1eaa90d..1730c4a 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleWriter.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/SimpleTupleWriter.java
@@ -13,15 +13,15 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.tuples;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
 import java.nio.ByteBuffer;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
 
-public class SimpleTupleWriter implements IBTreeTupleWriter {
+public class SimpleTupleWriter implements ITreeIndexTupleWriter {
 
     @Override
     public int bytesRequired(ITupleReference tuple) {
@@ -42,7 +42,7 @@
     }
 
     @Override
-    public IBTreeTupleReference createTupleReference() {
+    public ITreeIndexTupleReference createTupleReference() {
         return new SimpleTupleReference();
     }
 
@@ -58,11 +58,11 @@
 
         int fieldEndOff = 0;
         for (int i = 0; i < tuple.getFieldCount(); i++) {
-            System.arraycopy(tuple.getFieldData(i), tuple.getFieldStart(i), targetBuf.array(), runner, tuple
-                    .getFieldLength(i));
+            System.arraycopy(tuple.getFieldData(i), tuple.getFieldStart(i), targetBuf.array(), runner,
+                    tuple.getFieldLength(i));
             fieldEndOff += tuple.getFieldLength(i);
             runner += tuple.getFieldLength(i);
-            targetBuf.putInt(targetOff + nullFlagsBytes + i * 4, fieldEndOff);
+            targetBuf.putShort(targetOff + nullFlagsBytes + i * 2, (short) fieldEndOff);
         }
 
         return runner - targetOff;
@@ -81,30 +81,30 @@
         int fieldEndOff = 0;
         int fieldCounter = 0;
         for (int i = startField; i < startField + numFields; i++) {
-            System.arraycopy(tuple.getFieldData(i), tuple.getFieldStart(i), targetBuf.array(), runner, tuple
-                    .getFieldLength(i));
+            System.arraycopy(tuple.getFieldData(i), tuple.getFieldStart(i), targetBuf.array(), runner,
+                    tuple.getFieldLength(i));
             fieldEndOff += tuple.getFieldLength(i);
             runner += tuple.getFieldLength(i);
-            targetBuf.putInt(targetOff + nullFlagsBytes + fieldCounter * 4, fieldEndOff);
+            targetBuf.putShort(targetOff + nullFlagsBytes + fieldCounter * 2, (short) fieldEndOff);
             fieldCounter++;
         }
 
         return runner - targetOff;
     }
 
-    private int getNullFlagsBytes(ITupleReference tuple) {
+    protected int getNullFlagsBytes(ITupleReference tuple) {
         return (int) Math.ceil((double) tuple.getFieldCount() / 8.0);
     }
 
-    private int getFieldSlotsBytes(ITupleReference tuple) {
-        return tuple.getFieldCount() * 4;
+    protected int getFieldSlotsBytes(ITupleReference tuple) {
+        return tuple.getFieldCount() * 2;
     }
 
-    private int getNullFlagsBytes(ITupleReference tuple, int startField, int numFields) {
+    protected int getNullFlagsBytes(ITupleReference tuple, int startField, int numFields) {
         return (int) Math.ceil((double) numFields / 8.0);
     }
 
-    private int getFieldSlotsBytes(ITupleReference tuple, int startField, int numFields) {
-        return numFields * 4;
+    protected int getFieldSlotsBytes(ITupleReference tuple, int startField, int numFields) {
+        return numFields * 2;
     }
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleWriterFactory.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/SimpleTupleWriterFactory.java
similarity index 68%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleWriterFactory.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/SimpleTupleWriterFactory.java
index 3b06153..ebb2905 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleWriterFactory.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/SimpleTupleWriterFactory.java
@@ -13,17 +13,17 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.tuples;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriterFactory;
 
-public class SimpleTupleWriterFactory implements IBTreeTupleWriterFactory {
+public class SimpleTupleWriterFactory implements ITreeIndexTupleWriterFactory {
 
     private static final long serialVersionUID = 1L;
 
     @Override
-    public IBTreeTupleWriter createTupleWriter() {
+    public ITreeIndexTupleWriter createTupleWriter() {
         return new SimpleTupleWriter();
     }
 
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleReference.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/TypeAwareTupleReference.java
similarity index 82%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleReference.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/TypeAwareTupleReference.java
index b82adb8..4f571b3 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleReference.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/TypeAwareTupleReference.java
@@ -13,15 +13,15 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.tuples;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
 import java.nio.ByteBuffer;
 
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
 
-public class TypeAwareTupleReference implements IBTreeTupleReference {
+public class TypeAwareTupleReference implements ITreeIndexTupleReference {
     protected ByteBuffer buf;
     protected int fieldStartIndex;
     protected int fieldCount;
@@ -29,9 +29,9 @@
     protected int nullFlagsBytes;
     protected int dataStartOff;
 
-    private ITypeTrait[] typeTraits;
-    private VarLenIntEncoderDecoder encDec = new VarLenIntEncoderDecoder();
-    private int[] decodedFieldSlots;
+    protected ITypeTrait[] typeTraits;
+    protected VarLenIntEncoderDecoder encDec = new VarLenIntEncoderDecoder();
+    protected int[] decodedFieldSlots;
 
     public TypeAwareTupleReference(ITypeTrait[] typeTraits) {
         this.typeTraits = typeTraits;
@@ -39,7 +39,7 @@
     }
 
     @Override
-    public void resetByOffset(ByteBuffer buf, int tupleStartOff) {
+    public void resetByTupleOffset(ByteBuffer buf, int tupleStartOff) {
         this.buf = buf;
         this.tupleStartOff = tupleStartOff;
 
@@ -62,8 +62,8 @@
     }
 
     @Override
-    public void resetByTupleIndex(IBTreeFrame frame, int tupleIndex) {
-        resetByOffset(frame.getBuffer(), frame.getTupleOffset(tupleIndex));
+    public void resetByTupleIndex(ITreeIndexFrame frame, int tupleIndex) {
+        resetByTupleOffset(frame.getBuffer(), frame.getTupleOffset(tupleIndex));
     }
 
     @Override
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriter.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/TypeAwareTupleWriter.java
similarity index 79%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriter.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/TypeAwareTupleWriter.java
index c975dae..81b48e5 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriter.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/TypeAwareTupleWriter.java
@@ -13,19 +13,19 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.tuples;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
 import java.nio.ByteBuffer;
 
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleReference;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
 
-public class TypeAwareTupleWriter implements IBTreeTupleWriter {
+public class TypeAwareTupleWriter implements ITreeIndexTupleWriter {
 
-    private ITypeTrait[] typeTraits;
-    private VarLenIntEncoderDecoder encDec = new VarLenIntEncoderDecoder();
+    protected ITypeTrait[] typeTraits;
+    protected VarLenIntEncoderDecoder encDec = new VarLenIntEncoderDecoder();
 
     public TypeAwareTupleWriter(ITypeTrait[] typeTraits) {
         this.typeTraits = typeTraits;
@@ -42,7 +42,7 @@
 
     @Override
     public int bytesRequired(ITupleReference tuple, int startField, int numFields) {
-        int bytes = getNullFlagsBytes(tuple, startField, numFields) + getFieldSlotsBytes(tuple, startField, numFields);
+        int bytes = getNullFlagsBytes(numFields) + getFieldSlotsBytes(tuple, startField, numFields);
         for (int i = startField; i < startField + numFields; i++) {
             bytes += tuple.getFieldLength(i);
         }
@@ -50,7 +50,7 @@
     }
 
     @Override
-    public IBTreeTupleReference createTupleReference() {
+    public ITreeIndexTupleReference createTupleReference() {
         return new TypeAwareTupleReference(typeTraits);
     }
 
@@ -74,8 +74,8 @@
 
         // write data fields
         for (int i = 0; i < tuple.getFieldCount(); i++) {
-            System.arraycopy(tuple.getFieldData(i), tuple.getFieldStart(i), targetBuf.array(), runner, tuple
-                    .getFieldLength(i));
+            System.arraycopy(tuple.getFieldData(i), tuple.getFieldStart(i), targetBuf.array(), runner,
+                    tuple.getFieldLength(i));
             runner += tuple.getFieldLength(i);
         }
 
@@ -86,7 +86,7 @@
     public int writeTupleFields(ITupleReference tuple, int startField, int numFields, ByteBuffer targetBuf,
             int targetOff) {
         int runner = targetOff;
-        int nullFlagsBytes = getNullFlagsBytes(tuple, startField, numFields);
+        int nullFlagsBytes = getNullFlagsBytes(numFields);
         // write null indicator bits
         for (int i = 0; i < nullFlagsBytes; i++) {
             targetBuf.put(runner++, (byte) 0);
@@ -102,19 +102,19 @@
         runner = encDec.getPos();
 
         for (int i = startField; i < startField + numFields; i++) {
-            System.arraycopy(tuple.getFieldData(i), tuple.getFieldStart(i), targetBuf.array(), runner, tuple
-                    .getFieldLength(i));
+            System.arraycopy(tuple.getFieldData(i), tuple.getFieldStart(i), targetBuf.array(), runner,
+                    tuple.getFieldLength(i));
             runner += tuple.getFieldLength(i);
         }
 
         return runner - targetOff;
     }
 
-    private int getNullFlagsBytes(ITupleReference tuple) {
+    protected int getNullFlagsBytes(ITupleReference tuple) {
         return (int) Math.ceil((double) tuple.getFieldCount() / 8.0);
     }
 
-    private int getFieldSlotsBytes(ITupleReference tuple) {
+    protected int getFieldSlotsBytes(ITupleReference tuple) {
         int fieldSlotBytes = 0;
         for (int i = 0; i < tuple.getFieldCount(); i++) {
             if (typeTraits[i].getStaticallyKnownDataLength() == ITypeTrait.VARIABLE_LENGTH) {
@@ -124,11 +124,11 @@
         return fieldSlotBytes;
     }
 
-    private int getNullFlagsBytes(ITupleReference tuple, int startField, int numFields) {
+    protected int getNullFlagsBytes(int numFields) {
         return (int) Math.ceil((double) numFields / 8.0);
     }
 
-    private int getFieldSlotsBytes(ITupleReference tuple, int startField, int numFields) {
+    protected int getFieldSlotsBytes(ITupleReference tuple, int startField, int numFields) {
         int fieldSlotBytes = 0;
         for (int i = startField; i < startField + numFields; i++) {
             if (typeTraits[i].getStaticallyKnownDataLength() == ITypeTrait.VARIABLE_LENGTH) {
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriterFactory.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/TypeAwareTupleWriterFactory.java
similarity index 73%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriterFactory.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/TypeAwareTupleWriterFactory.java
index bfaa120..82072ae 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriterFactory.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/TypeAwareTupleWriterFactory.java
@@ -13,13 +13,13 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.tuples;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriterFactory;
 
-public class TypeAwareTupleWriterFactory implements IBTreeTupleWriterFactory {
+public class TypeAwareTupleWriterFactory implements ITreeIndexTupleWriterFactory {
 
     private static final long serialVersionUID = 1L;
     private ITypeTrait[] typeTraits;
@@ -29,7 +29,7 @@
     }
 
     @Override
-    public IBTreeTupleWriter createTupleWriter() {
+    public ITreeIndexTupleWriter createTupleWriter() {
         return new TypeAwareTupleWriter(typeTraits);
     }
 
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/VarLenIntEncoderDecoder.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/VarLenIntEncoderDecoder.java
similarity index 97%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/VarLenIntEncoderDecoder.java
rename to hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/VarLenIntEncoderDecoder.java
index 8e40855..d266d41 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/VarLenIntEncoderDecoder.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/tuples/VarLenIntEncoderDecoder.java
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.tuples;
+package edu.uci.ics.hyracks.storage.am.common.tuples;
 
 // encodes positive integers in a variable-byte format
 
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/utility/TreeIndexBufferCacheWarmup.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/utility/TreeIndexBufferCacheWarmup.java
new file mode 100644
index 0000000..eb261da
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/utility/TreeIndexBufferCacheWarmup.java
@@ -0,0 +1,84 @@
+package edu.uci.ics.hyracks.storage.am.common.utility;
+
+import java.util.ArrayList;
+import java.util.Random;
+
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IntArrayList;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
+
+public class TreeIndexBufferCacheWarmup {
+    private final IBufferCache bufferCache;
+    private final IFreePageManager freePageManager;
+    private final int fileId;
+    private final ArrayList<IntArrayList> pagesByLevel = new ArrayList<IntArrayList>();
+    private final Random rnd = new Random();
+
+    public TreeIndexBufferCacheWarmup(IBufferCache bufferCache, IFreePageManager freePageManager, int fileId) {
+        this.bufferCache = bufferCache;
+        this.freePageManager = freePageManager;
+        this.fileId = fileId;
+    }
+
+    public void warmup(ITreeIndexFrame frame, ITreeIndexMetaDataFrame metaFrame, int[] warmupTreeLevels,
+            int[] warmupRepeats) throws HyracksDataException {
+        bufferCache.openFile(fileId);
+
+        // scan entire file to determine pages in each level
+        int maxPageId = freePageManager.getMaxPage(metaFrame);
+        for (int pageId = 0; pageId <= maxPageId; pageId++) {
+            ICachedPage page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+            page.acquireReadLatch();
+            try {
+                frame.setPage(page);
+                byte level = frame.getLevel();
+                while (level >= pagesByLevel.size()) {
+                    pagesByLevel.add(new IntArrayList(100, 100));
+                }
+                if (level >= 0) {
+                    // System.out.println("ADDING: " + level + " " + pageId);
+                    pagesByLevel.get(level).add(pageId);
+                }
+            } finally {
+                page.releaseReadLatch();
+                bufferCache.unpin(page);
+            }
+        }
+
+        // pin certain pages again to simulate frequent access
+        for (int i = 0; i < warmupTreeLevels.length; i++) {
+            if (warmupTreeLevels[i] < pagesByLevel.size()) {
+                int repeats = warmupRepeats[i];
+                IntArrayList pageIds = pagesByLevel.get(warmupTreeLevels[i]);
+                int[] remainingPageIds = new int[pageIds.size()];
+                for (int r = 0; r < repeats; r++) {
+                    for (int j = 0; j < pageIds.size(); j++) {
+                        remainingPageIds[j] = pageIds.get(j);
+                    }
+
+                    int remainingLength = pageIds.size();
+                    for (int j = 0; j < pageIds.size(); j++) {
+                        int index = Math.abs(rnd.nextInt()) % remainingLength;
+                        int pageId = remainingPageIds[index];
+
+                        // pin & latch then immediately unlatch & unpin
+                        ICachedPage page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+                        page.acquireReadLatch();
+                        page.releaseReadLatch();
+                        bufferCache.unpin(page);
+
+                        remainingPageIds[index] = remainingPageIds[remainingLength - 1];
+                        remainingLength--;
+                    }
+                }
+            }
+        }
+
+        bufferCache.closeFile(fileId);
+    }
+}
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/utility/TreeIndexStats.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/utility/TreeIndexStats.java
new file mode 100644
index 0000000..5b01b2d
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/utility/TreeIndexStats.java
@@ -0,0 +1,134 @@
+package edu.uci.ics.hyracks.storage.am.common.utility;
+
+import java.text.DecimalFormat;
+
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+
+public class TreeIndexStats {
+
+    private TreeIndexNodeTypeStats rootStats = new TreeIndexNodeTypeStats();
+    private TreeIndexNodeTypeStats interiorStats = new TreeIndexNodeTypeStats();
+    private TreeIndexNodeTypeStats leafStats = new TreeIndexNodeTypeStats();
+
+    private int freePages = 0;
+    private int metaPages = 0;
+    private int treeLevels = 0;
+
+    public void begin() {
+        rootStats.clear();
+        interiorStats.clear();
+        leafStats.clear();
+        freePages = 0;
+        metaPages = 0;
+        treeLevels = 0;
+    }
+
+    public void addRoot(ITreeIndexFrame frame) {
+        treeLevels = frame.getLevel() + 1;
+        rootStats.add(frame);
+    }
+
+    public void add(ITreeIndexFrame frame) {
+        if (frame.isLeaf()) {
+            leafStats.add(frame);
+        } else if (frame.isInterior()) {
+            interiorStats.add(frame);
+        }
+    }
+
+    public void add(ITreeIndexMetaDataFrame metaFrame, IFreePageManager freePageManager) {
+        if (freePageManager.isFreePage(metaFrame)) {
+            freePages++;
+        } else if (freePageManager.isMetaPage(metaFrame)) {
+            metaPages++;
+        }
+    }
+
+    public void end() {
+        // nothing here currently
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder strBuilder = new StringBuilder();
+        DecimalFormat df = new DecimalFormat("#####.##");
+
+        strBuilder.append("TREE LEVELS:  " + treeLevels + "\n");
+        strBuilder.append("FREE PAGES :  " + freePages + "\n");
+        strBuilder.append("META PAGES :  " + metaPages + "\n");
+        long totalPages = interiorStats.getNumPages() + leafStats.getNumPages() + freePages + metaPages;
+        strBuilder.append("TOTAL PAGES : " + totalPages + "\n");
+
+        strBuilder.append("\n");
+        strBuilder.append("ROOT STATS" + "\n");
+        strBuilder.append("NUM TUPLES:      " + rootStats.getNumTuples() + "\n");
+        strBuilder.append("FILL FACTOR    : " + df.format(rootStats.getAvgFillFactor()) + "\n");
+
+        if (interiorStats.getNumPages() > 0) {
+            strBuilder.append("\n");
+            strBuilder.append("INTERIOR STATS" + "\n");
+            strBuilder.append("NUM PAGES:       " + interiorStats.getNumPages() + "\n");
+            strBuilder.append("NUM TUPLES:      " + interiorStats.getNumTuples() + "\n");
+            strBuilder.append("AVG TUPLES/PAGE: " + df.format(interiorStats.getAvgNumTuples()) + "\n");
+            strBuilder.append("AVG FILL FACTOR: " + df.format(interiorStats.getAvgFillFactor()) + "\n");
+        }
+
+        if (leafStats.getNumPages() > 0) {
+            strBuilder.append("\n");
+            strBuilder.append("LEAF STATS" + "\n");
+            strBuilder.append("NUM PAGES:       " + df.format(leafStats.getNumPages()) + "\n");
+            strBuilder.append("NUM TUPLES:      " + df.format(leafStats.getNumTuples()) + "\n");
+            strBuilder.append("AVG TUPLES/PAGE: " + df.format(leafStats.getAvgNumTuples()) + "\n");
+            strBuilder.append("AVG FILL FACTOR: " + df.format(leafStats.getAvgFillFactor()) + "\n");
+        }
+
+        return strBuilder.toString();
+    }
+
+    public class TreeIndexNodeTypeStats {
+        private long numTuples;
+        private long sumTuplesSizes;
+        private long numPages;
+        private double sumFillFactors;
+
+        public void clear() {
+            numTuples = 0;
+            sumTuplesSizes = 0;
+            numPages = 0;
+        }
+
+        public void add(ITreeIndexFrame frame) {
+            numPages++;
+            numTuples += frame.getTupleCount();
+            sumFillFactors += (double) (frame.getBuffer().capacity() - frame.getTotalFreeSpace())
+                    / (double) frame.getBuffer().capacity();
+        }
+
+        public long getNumTuples() {
+            return numTuples;
+        }
+
+        public long getSumTupleSizes() {
+            return sumTuplesSizes;
+        }
+
+        public long getNumPages() {
+            return numPages;
+        }
+
+        public double getAvgNumTuples() {
+            return (double) numTuples / (double) numPages;
+        }
+
+        public double getAvgTupleSize() {
+            return (double) sumTuplesSizes / (double) numTuples;
+        }
+
+        public double getAvgFillFactor() {
+            return sumFillFactors / numPages;
+        }
+    }
+
+}
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/utility/TreeIndexStatsGatherer.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/utility/TreeIndexStatsGatherer.java
new file mode 100644
index 0000000..fc0ab5e
--- /dev/null
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/utility/TreeIndexStatsGatherer.java
@@ -0,0 +1,70 @@
+package edu.uci.ics.hyracks.storage.am.common.utility;
+
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
+
+public class TreeIndexStatsGatherer {
+
+    private final TreeIndexStats treeIndexStats = new TreeIndexStats();
+    private final IBufferCache bufferCache;
+    private final IFreePageManager freePageManager;
+    private final int fileId;
+    private final int rootPage;
+
+    public TreeIndexStatsGatherer(IBufferCache bufferCache, IFreePageManager freePageManager, int fileId, int rootPage) {
+        this.bufferCache = bufferCache;
+        this.freePageManager = freePageManager;
+        this.fileId = fileId;
+        this.rootPage = rootPage;
+    }
+
+    public TreeIndexStats gatherStats(ITreeIndexFrame leafFrame, ITreeIndexFrame interiorFrame,
+            ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException {
+
+        bufferCache.openFile(fileId);
+
+        treeIndexStats.begin();
+
+        int maxPageId = freePageManager.getMaxPage(metaFrame);
+        for (int pageId = 0; pageId <= maxPageId; pageId++) {
+            ICachedPage page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+            page.acquireReadLatch();
+            try {
+                metaFrame.setPage(page);
+                leafFrame.setPage(page);
+                interiorFrame.setPage(page);
+
+                if (leafFrame.isLeaf()) {
+                    if (pageId == rootPage) {
+                        treeIndexStats.addRoot(leafFrame);
+                    } else {
+                        treeIndexStats.add(leafFrame);
+                    }
+                } else if (interiorFrame.isInterior()) {
+                    if (pageId == rootPage) {
+                        treeIndexStats.addRoot(interiorFrame);
+                    } else {
+                        treeIndexStats.add(interiorFrame);
+                    }
+                } else {
+                    treeIndexStats.add(metaFrame, freePageManager);
+                }
+
+            } finally {
+                page.releaseReadLatch();
+                bufferCache.unpin(page);
+            }
+        }
+
+        treeIndexStats.end();
+
+        bufferCache.closeFile(fileId);
+
+        return treeIndexStats;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/pom.xml b/hyracks-storage-am-invertedindex/pom.xml
index 78a053c..ca40e57 100644
--- a/hyracks-storage-am-invertedindex/pom.xml
+++ b/hyracks-storage-am-invertedindex/pom.xml
@@ -58,7 +58,7 @@
   		<version>0.1.7-SNAPSHOT</version>
   		<type>jar</type>
   		<scope>compile</scope>
-  	</dependency>  	
+  	</dependency>    
   	<dependency>
   		<groupId>junit</groupId>
   		<artifactId>junit</artifactId>
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IBinaryTokenizer.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IBinaryTokenizer.java
deleted file mode 100644
index 0d5dc8f..0000000
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IBinaryTokenizer.java
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.invertedindex.api;
-
-import java.io.DataOutput;
-import java.io.IOException;
-
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-
-public interface IBinaryTokenizer {
-
-    public void reset(byte[] data, int start, int length);
-
-    public boolean hasNext();
-
-    public void next();
-
-    public int getTokenStartOff();
-
-    public int getTokenLength();
-
-    public int getNumTokens();
-
-    public void writeToken(DataOutput dos) throws IOException;
-
-    public RecordDescriptor getTokenSchema();
-}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexOperatorDescriptorHelper.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexOperatorDescriptorHelper.java
new file mode 100644
index 0000000..b3afe4a
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexOperatorDescriptorHelper.java
@@ -0,0 +1,33 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.api;
+
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOperatorDescriptorHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+
+public interface IInvertedIndexOperatorDescriptorHelper extends ITreeIndexOperatorDescriptorHelper {
+    public IFileSplitProvider getInvIndexFileSplitProvider();
+
+    public IBinaryComparatorFactory[] getInvIndexComparatorFactories();
+
+    public ITypeTrait[] getInvIndexTypeTraits();
+
+    public IIndexRegistryProvider<InvertedIndex> getInvIndexRegistryProvider();
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexResultCursor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexResultCursor.java
index 990936e..fb73a65 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexResultCursor.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexResultCursor.java
@@ -15,14 +15,14 @@
 
 package edu.uci.ics.hyracks.storage.am.invertedindex.api;
 
-import java.nio.ByteBuffer;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 
 public interface IInvertedIndexResultCursor {
     public boolean hasNext();
 
     public void next();
 
-    public ByteBuffer getBuffer();
+    public ITupleReference getTuple();
 
-    public void reset();
+    public void reset(IInvertedIndexSearcher invIndexSearcher);
 }
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IBinaryTokenizerFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexSearchModifier.java
similarity index 76%
rename from hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IBinaryTokenizerFactory.java
rename to hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexSearchModifier.java
index 7e91fd4..8f7a3e3 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IBinaryTokenizerFactory.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexSearchModifier.java
@@ -15,8 +15,10 @@
 
 package edu.uci.ics.hyracks.storage.am.invertedindex.api;
 
-import java.io.Serializable;
+import java.util.List;
 
-public interface IBinaryTokenizerFactory extends Serializable {
-    public IBinaryTokenizer createBinaryTokenizer();
+public interface IInvertedIndexSearchModifier {
+    int getOccurrenceThreshold(List<IInvertedListCursor> invListCursors);
+
+    int getPrefixLists(List<IInvertedListCursor> invListCursors);
 }
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexSearcher.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexSearcher.java
index 98dc3b9..36d64ea 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexSearcher.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedIndexSearcher.java
@@ -15,10 +15,21 @@
 
 package edu.uci.ics.hyracks.storage.am.invertedindex.api;
 
+import java.nio.ByteBuffer;
+import java.util.List;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 
 public interface IInvertedIndexSearcher {
-    public void search(ITupleReference queryTuple, int queryFieldIndex) throws Exception;
+    public void search(IInvertedIndexResultCursor resultCursor, ITupleReference queryTuple, int queryFieldIndex,
+            IInvertedIndexSearchModifier searchModifier) throws Exception;
 
-    public IInvertedIndexResultCursor getResultCursor();
+    public IFrameTupleAccessor createResultFrameTupleAccessor();
+
+    public ITupleReference createResultTupleReference();
+
+    public List<ByteBuffer> getResultBuffers();
+
+    public int getNumValidResultBuffers();
 }
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListBuilder.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListBuilder.java
new file mode 100644
index 0000000..aaaef56
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListBuilder.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.api;
+
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+
+public interface IInvertedListBuilder {
+    public boolean startNewList(ITupleReference tuple, int numTokenFields);
+
+    // returns true if successfully appended
+    // returns false if not enough space in targetBuf
+    public boolean appendElement(ITupleReference tuple, int numTokenFields, int numElementFields);
+
+    public void setTargetBuffer(byte[] targetBuf, int startPos);
+
+    public int getListSize();
+
+    public int getPos();
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListCursor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListCursor.java
new file mode 100644
index 0000000..9435f3c
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IInvertedListCursor.java
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.api;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+
+public interface IInvertedListCursor extends Comparable<IInvertedListCursor> {
+    void reset(int startPageId, int endPageId, int startOff, int numElements);
+
+    void pinPagesSync() throws HyracksDataException;
+
+    void pinPagesAsync() throws HyracksDataException;
+
+    void unpinPages() throws HyracksDataException;
+
+    boolean hasNext();
+
+    void next();
+
+    ITupleReference getTuple();
+
+    // getters
+    int getNumElements();
+
+    int getStartPageId();
+
+    int getEndPageId();
+
+    int getStartOff();
+
+    // jump to a specific element
+    void positionCursor(int elementIx);
+
+    boolean containsKey(ITupleReference searchTuple, MultiComparator invListCmp);
+
+    // for debugging
+    String printInvList(ISerializerDeserializer[] serdes) throws HyracksDataException;
+
+    String printCurrentElement(ISerializerDeserializer[] serdes) throws HyracksDataException;
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/AbstractInvertedIndexOperatorDescriptor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/AbstractInvertedIndexOperatorDescriptor.java
new file mode 100644
index 0000000..0d0c5bf
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/AbstractInvertedIndexOperatorDescriptor.java
@@ -0,0 +1,151 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.dataflow;
+
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.job.JobSpecification;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexOperatorDescriptorHelper;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+
+public abstract class AbstractInvertedIndexOperatorDescriptor extends AbstractSingleActivityOperatorDescriptor
+        implements IInvertedIndexOperatorDescriptorHelper {
+
+    private static final long serialVersionUID = 1L;
+
+    // general
+    protected final IStorageManagerInterface storageManager;
+
+    // btree
+    protected final IFileSplitProvider btreeFileSplitProvider;
+    protected final IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider;
+    protected final ITreeIndexFrameFactory interiorFrameFactory;
+    protected final ITreeIndexFrameFactory leafFrameFactory;
+    protected final ITypeTrait[] btreeTypeTraits;
+    protected final IBinaryComparatorFactory[] btreeComparatorFactories;
+    protected final ITreeIndexOpHelperFactory opHelperFactory;
+
+    // inverted index
+    protected final IFileSplitProvider invIndexFileSplitProvider;
+    protected final IIndexRegistryProvider<InvertedIndex> invIndexRegistryProvider;
+    protected final ITypeTrait[] invIndexTypeTraits;
+    protected final IBinaryComparatorFactory[] invIndexComparatorFactories;
+
+    public AbstractInvertedIndexOperatorDescriptor(JobSpecification spec, int inputArity, int outputArity,
+            RecordDescriptor recDesc, IStorageManagerInterface storageManager,
+            IFileSplitProvider btreeFileSplitProvider, IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider,
+            ITreeIndexFrameFactory interiorFrameFactory, ITreeIndexFrameFactory leafFrameFactory,
+            ITypeTrait[] btreeTypeTraits, IBinaryComparatorFactory[] btreeComparatorFactories, float btreeFillFactor,
+            ITreeIndexOpHelperFactory opHelperFactory, IFileSplitProvider invIndexFileSplitProvider,
+            IIndexRegistryProvider<InvertedIndex> invIndexRegistryProvider, ITypeTrait[] invIndexTypeTraits,
+            IBinaryComparatorFactory[] invIndexComparatorFactories) {
+        super(spec, inputArity, outputArity);
+
+        // general
+        this.storageManager = storageManager;
+
+        // btree
+        this.btreeFileSplitProvider = btreeFileSplitProvider;
+        this.treeIndexRegistryProvider = treeIndexRegistryProvider;
+        this.interiorFrameFactory = interiorFrameFactory;
+        this.leafFrameFactory = leafFrameFactory;
+        this.btreeTypeTraits = btreeTypeTraits;
+        this.btreeComparatorFactories = btreeComparatorFactories;
+        this.opHelperFactory = opHelperFactory;
+
+        // inverted index
+        this.invIndexFileSplitProvider = invIndexFileSplitProvider;
+        this.invIndexRegistryProvider = invIndexRegistryProvider;
+        this.invIndexTypeTraits = invIndexTypeTraits;
+        this.invIndexComparatorFactories = invIndexComparatorFactories;
+
+        if (outputArity > 0)
+            recordDescriptors[0] = recDesc;
+    }
+
+    @Override
+    public IFileSplitProvider getTreeIndexFileSplitProvider() {
+        return btreeFileSplitProvider;
+    }
+
+    @Override
+    public IBinaryComparatorFactory[] getTreeIndexComparatorFactories() {
+        return btreeComparatorFactories;
+    }
+
+    @Override
+    public ITypeTrait[] getTreeIndexTypeTraits() {
+        return btreeTypeTraits;
+    }
+
+    @Override
+    public ITreeIndexFrameFactory getTreeIndexInteriorFactory() {
+        return interiorFrameFactory;
+    }
+
+    @Override
+    public ITreeIndexFrameFactory getTreeIndexLeafFactory() {
+        return leafFrameFactory;
+    }
+
+    @Override
+    public IStorageManagerInterface getStorageManager() {
+        return storageManager;
+    }
+
+    @Override
+    public IIndexRegistryProvider<ITreeIndex> getTreeIndexRegistryProvider() {
+        return treeIndexRegistryProvider;
+    }
+
+    @Override
+    public RecordDescriptor getRecordDescriptor() {
+        return recordDescriptors[0];
+    }
+
+    @Override
+    public IIndexRegistryProvider<InvertedIndex> getInvIndexRegistryProvider() {
+        return invIndexRegistryProvider;
+    }
+
+    @Override
+    public IBinaryComparatorFactory[] getInvIndexComparatorFactories() {
+        return invIndexComparatorFactories;
+    }
+
+    @Override
+    public IFileSplitProvider getInvIndexFileSplitProvider() {
+        return invIndexFileSplitProvider;
+    }
+
+    @Override
+    public ITypeTrait[] getInvIndexTypeTraits() {
+        return invIndexTypeTraits;
+    }
+
+    @Override
+    public ITreeIndexOpHelperFactory getTreeIndexOpHelperFactory() {
+        return opHelperFactory;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/BinaryTokenizerOperatorDescriptor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/BinaryTokenizerOperatorDescriptor.java
index 059a1e2..83246d6 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/BinaryTokenizerOperatorDescriptor.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/BinaryTokenizerOperatorDescriptor.java
@@ -23,7 +23,7 @@
 import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
 import edu.uci.ics.hyracks.api.job.JobSpecification;
 import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizerFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizerFactory;
 
 public class BinaryTokenizerOperatorDescriptor extends AbstractSingleActivityOperatorDescriptor {
 
@@ -50,6 +50,6 @@
     public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
             IRecordDescriptorProvider recordDescProvider, int partition, int nPartitions) throws HyracksDataException {
         return new BinaryTokenizerOperatorNodePushable(ctx, recordDescProvider.getInputRecordDescriptor(odId, 0),
-                recordDescriptors[0], tokenizerFactory.createBinaryTokenizer(), tokenFields, projFields);
+                recordDescriptors[0], tokenizerFactory.createTokenizer(), tokenFields, projFields);
     }
 }
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/BinaryTokenizerOperatorNodePushable.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/BinaryTokenizerOperatorNodePushable.java
index 9dac535..0647f45 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/BinaryTokenizerOperatorNodePushable.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/BinaryTokenizerOperatorNodePushable.java
@@ -27,7 +27,8 @@
 import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
 import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
 import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputUnaryOutputOperatorNodePushable;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizer;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizer;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IToken;
 
 public class BinaryTokenizerOperatorNodePushable extends AbstractUnaryInputUnaryOutputOperatorNodePushable {
 
@@ -84,7 +85,8 @@
 
                     builder.reset();
                     try {
-                        tokenizer.writeToken(builderDos);
+                        IToken token = tokenizer.getToken();
+                        token.serializeToken(builderDos);
                         builder.addFieldEndOffset();
                     } catch (IOException e) {
                         throw new HyracksDataException(e.getMessage());
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorDescriptor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorDescriptor.java
new file mode 100644
index 0000000..d003580
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorDescriptor.java
@@ -0,0 +1,65 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
+import edu.uci.ics.hyracks.api.job.JobSpecification;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+
+public class InvertedIndexBulkLoadOperatorDescriptor extends AbstractInvertedIndexOperatorDescriptor {
+
+    private static final long serialVersionUID = 1L;
+
+    private final int[] fieldPermutation;
+    private final float btreeFillFactor;
+    private final IInvertedListBuilder invListBuilder;
+
+    public InvertedIndexBulkLoadOperatorDescriptor(JobSpecification spec, IStorageManagerInterface storageManager,
+            int[] fieldPermutation, IFileSplitProvider btreeFileSplitProvider,
+            IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider, ITreeIndexFrameFactory interiorFrameFactory,
+            ITreeIndexFrameFactory leafFrameFactory, ITypeTrait[] btreeTypeTraits,
+            IBinaryComparatorFactory[] btreeComparatorFactories, float btreeFillFactor,
+            ITreeIndexOpHelperFactory opHelperFactory, IFileSplitProvider invIndexFileSplitProvider,
+            IIndexRegistryProvider<InvertedIndex> invIndexRegistryProvider, ITypeTrait[] invIndexTypeTraits,
+            IBinaryComparatorFactory[] invIndexComparatorFactories, IInvertedListBuilder invListBuilder) {
+        super(spec, 1, 0, null, storageManager, btreeFileSplitProvider, treeIndexRegistryProvider,
+                interiorFrameFactory, leafFrameFactory, btreeTypeTraits, btreeComparatorFactories, btreeFillFactor,
+                opHelperFactory, invIndexFileSplitProvider, invIndexRegistryProvider, invIndexTypeTraits,
+                invIndexComparatorFactories);
+        this.fieldPermutation = fieldPermutation;
+        this.btreeFillFactor = btreeFillFactor;
+        this.invListBuilder = invListBuilder;
+    }
+
+    @Override
+    public IOperatorNodePushable createPushRuntime(IHyracksStageletContext ctx, IOperatorEnvironment env,
+            IRecordDescriptorProvider recordDescProvider, int partition, int nPartitions) {
+        return new InvertedIndexBulkLoadOperatorNodePushable(this, ctx, partition, fieldPermutation, btreeFillFactor,
+                invListBuilder, recordDescProvider);
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorNodePushable.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorNodePushable.java
new file mode 100644
index 0000000..4969124
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexBulkLoadOperatorNodePushable.java
@@ -0,0 +1,111 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.storage.am.invertedindex.dataflow;
+
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputSinkOperatorNodePushable;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexHelperOpenMode;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.PermutingFrameTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexOpHelper;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+
+public class InvertedIndexBulkLoadOperatorNodePushable extends AbstractUnaryInputSinkOperatorNodePushable {
+    private final TreeIndexOpHelper treeIndexOpHelper;
+    private float btreeFillFactor;
+
+    private final InvertedIndexOpHelper invIndexOpHelper;
+    protected final IInvertedListBuilder invListBuilder;
+    private InvertedIndex.BulkLoadContext bulkLoadCtx;
+
+    private final IHyracksStageletContext ctx;
+
+    private FrameTupleAccessor accessor;
+    private PermutingFrameTupleReference tuple = new PermutingFrameTupleReference();
+
+    private IRecordDescriptorProvider recordDescProvider;
+
+    public InvertedIndexBulkLoadOperatorNodePushable(AbstractInvertedIndexOperatorDescriptor opDesc,
+            IHyracksStageletContext ctx, int partition, int[] fieldPermutation, float btreeFillFactor,
+            IInvertedListBuilder invListBuilder, IRecordDescriptorProvider recordDescProvider) {
+        treeIndexOpHelper = opDesc.getTreeIndexOpHelperFactory().createTreeIndexOpHelper(opDesc, ctx, partition,
+                IndexHelperOpenMode.CREATE);
+        invIndexOpHelper = new InvertedIndexOpHelper(opDesc, ctx, partition, IndexHelperOpenMode.CREATE);
+        this.btreeFillFactor = btreeFillFactor;
+        this.recordDescProvider = recordDescProvider;
+        this.ctx = ctx;
+        this.invListBuilder = invListBuilder;
+        tuple.setFieldPermutation(fieldPermutation);
+    }
+
+    @Override
+    public void open() throws HyracksDataException {
+        AbstractInvertedIndexOperatorDescriptor opDesc = (AbstractInvertedIndexOperatorDescriptor) treeIndexOpHelper
+                .getOperatorDescriptor();
+        RecordDescriptor recDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getOperatorId(), 0);
+        accessor = new FrameTupleAccessor(treeIndexOpHelper.getHyracksStageletContext().getFrameSize(), recDesc);
+
+        // btree
+        try {
+            treeIndexOpHelper.init();
+            treeIndexOpHelper.getTreeIndex().open(treeIndexOpHelper.getIndexFileId());
+        } catch (Exception e) {
+            // cleanup in case of failure
+            treeIndexOpHelper.deinit();
+            throw new HyracksDataException(e);
+        }
+
+        // inverted index
+        try {
+            invIndexOpHelper.init();
+            invIndexOpHelper.getInvIndex().open(invIndexOpHelper.getInvIndexFileId());
+            bulkLoadCtx = invIndexOpHelper.getInvIndex().beginBulkLoad(invListBuilder, ctx.getFrameSize(),
+                    btreeFillFactor);
+        } catch (Exception e) {
+            // cleanup in case of failure
+            invIndexOpHelper.deinit();
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
+        accessor.reset(buffer);
+        int tupleCount = accessor.getTupleCount();
+        for (int i = 0; i < tupleCount; i++) {
+            tuple.reset(accessor, i);
+            invIndexOpHelper.getInvIndex().bulkLoadAddTuple(bulkLoadCtx, tuple);
+        }
+    }
+
+    @Override
+    public void close() throws HyracksDataException {
+        try {
+            invIndexOpHelper.getInvIndex().endBulkLoad(bulkLoadCtx);
+        } finally {
+            treeIndexOpHelper.deinit();
+        }
+    }
+
+    @Override
+    public void flush() throws HyracksDataException {
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexOpHelper.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexOpHelper.java
new file mode 100644
index 0000000..c16cfcd
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/dataflow/InvertedIndexOpHelper.java
@@ -0,0 +1,158 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package edu.uci.ics.hyracks.storage.am.invertedindex.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOperatorDescriptorHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexHelperOpenMode;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexRegistry;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexOperatorDescriptorHelper;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+
+public final class InvertedIndexOpHelper {
+
+    private InvertedIndex invIndex;
+    private int invIndexFileId = -1;
+    private int partition;
+
+    private IInvertedIndexOperatorDescriptorHelper opDesc;
+    private IHyracksStageletContext ctx;
+
+    private IndexHelperOpenMode mode;
+
+    public InvertedIndexOpHelper(IInvertedIndexOperatorDescriptorHelper opDesc, final IHyracksStageletContext ctx,
+            int partition, IndexHelperOpenMode mode) {
+        this.opDesc = opDesc;
+        this.ctx = ctx;
+        this.mode = mode;
+        this.partition = partition;
+    }
+
+    public void init() throws HyracksDataException {
+        IBufferCache bufferCache = opDesc.getStorageManager().getBufferCache(ctx);
+        IFileMapProvider fileMapProvider = opDesc.getStorageManager().getFileMapProvider(ctx);
+        IFileSplitProvider fileSplitProvider = opDesc.getInvIndexFileSplitProvider();
+
+        FileReference f = fileSplitProvider.getFileSplits()[partition].getLocalFile();
+        boolean fileIsMapped = fileMapProvider.isMapped(f);
+
+        switch (mode) {
+
+            case OPEN: {
+                if (!fileIsMapped) {
+                    throw new HyracksDataException("Trying to open inverted index from unmapped file " + f.toString());
+                }
+            }
+                break;
+
+            case CREATE:
+            case ENLIST: {
+                if (!fileIsMapped) {
+                    bufferCache.createFile(f);
+                }
+            }
+                break;
+
+        }
+
+        int fileId = fileMapProvider.lookupFileId(f);
+        try {
+            bufferCache.openFile(fileId);
+        } catch (HyracksDataException e) {
+            // revert state of buffer cache since file failed to open
+            if (!fileIsMapped) {
+                bufferCache.deleteFile(fileId);
+            }
+            throw e;
+        }
+
+        // only set btreeFileId member when openFile() succeeds,
+        // otherwise deinit() will try to close the file that failed to open
+        invIndexFileId = fileId;
+        IndexRegistry<InvertedIndex> invIndexRegistry = opDesc.getInvIndexRegistryProvider().getRegistry(ctx);
+        invIndex = invIndexRegistry.get(invIndexFileId);
+        if (invIndex == null) {
+
+            // create new inverted index and register it
+            invIndexRegistry.lock();
+            try {
+                // check if inverted index has already been registered by
+                // another thread
+                invIndex = invIndexRegistry.get(invIndexFileId);
+                if (invIndex == null) {
+                    // this thread should create and register the inverted index
+
+                    IBinaryComparator[] comparators = new IBinaryComparator[opDesc.getInvIndexComparatorFactories().length];
+                    for (int i = 0; i < opDesc.getInvIndexComparatorFactories().length; i++) {
+                        comparators[i] = opDesc.getInvIndexComparatorFactories()[i].createBinaryComparator();
+                    }
+
+                    MultiComparator cmp = new MultiComparator(opDesc.getInvIndexTypeTraits(), comparators);
+
+                    // assumes btree has already been registered
+                    IFileSplitProvider btreeFileSplitProvider = opDesc.getTreeIndexFileSplitProvider();
+                    IndexRegistry<ITreeIndex> treeIndexRegistry = opDesc.getTreeIndexRegistryProvider()
+                            .getRegistry(ctx);
+                    FileReference btreeFile = btreeFileSplitProvider.getFileSplits()[partition].getLocalFile();
+                    boolean btreeFileIsMapped = fileMapProvider.isMapped(btreeFile);
+                    if (!btreeFileIsMapped) {
+                        throw new HyracksDataException(
+                                "Trying to create inverted index, but associated BTree file has not been mapped");
+                    }
+                    int btreeFileId = fileMapProvider.lookupFileId(f);
+                    BTree btree = (BTree) treeIndexRegistry.get(btreeFileId);
+
+                    invIndex = new InvertedIndex(bufferCache, btree, cmp);
+                    invIndex.open(invIndexFileId);
+                    invIndexRegistry.register(invIndexFileId, invIndex);
+                }
+            } finally {
+                invIndexRegistry.unlock();
+            }
+        }
+    }
+
+    public void deinit() throws HyracksDataException {
+        if (invIndexFileId != -1) {
+            IBufferCache bufferCache = opDesc.getStorageManager().getBufferCache(ctx);
+            bufferCache.closeFile(invIndexFileId);
+        }
+    }
+
+    public InvertedIndex getInvIndex() {
+        return invIndex;
+    }
+
+    public IHyracksStageletContext getHyracksStageletContext() {
+        return ctx;
+    }
+
+    public ITreeIndexOperatorDescriptorHelper getOperatorDescriptor() {
+        return opDesc;
+    }
+
+    public int getInvIndexFileId() {
+        return invIndexFileId;
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListBuilder.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListBuilder.java
new file mode 100644
index 0000000..03fc9a1
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListBuilder.java
@@ -0,0 +1,79 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
+
+public class FixedSizeElementInvertedListBuilder implements IInvertedListBuilder {
+    private final int listElementSize;
+    private int listSize = 0;
+
+    private byte[] targetBuf;
+    private int pos;
+
+    public FixedSizeElementInvertedListBuilder(ITypeTrait[] invListFields) {
+        int tmp = 0;
+        for (int i = 0; i < invListFields.length; i++) {
+            tmp += invListFields[i].getStaticallyKnownDataLength();
+        }
+        listElementSize = tmp;
+    }
+
+    @Override
+    public boolean startNewList(ITupleReference tuple, int tokenField) {
+        if (pos + listElementSize > targetBuf.length)
+            return false;
+        else {
+            listSize = 0;
+            return true;
+        }
+    }
+
+    @Override
+    public boolean appendElement(ITupleReference tuple, int numTokenFields, int numElementFields) {
+        if (pos + listElementSize > targetBuf.length)
+            return false;
+
+        for (int i = 0; i < numElementFields; i++) {
+            int field = numTokenFields + i;
+            System.arraycopy(tuple.getFieldData(field), tuple.getFieldStart(field), targetBuf, pos,
+                    tuple.getFieldLength(field));
+        }
+
+        listSize++;
+        pos += listElementSize;
+
+        return true;
+    }
+
+    @Override
+    public void setTargetBuffer(byte[] targetBuf, int startPos) {
+        this.targetBuf = targetBuf;
+        this.pos = startPos;
+    }
+
+    @Override
+    public int getListSize() {
+        return listSize;
+    }
+
+    @Override
+    public int getPos() {
+        return pos;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListCursor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListCursor.java
new file mode 100644
index 0000000..f7ef56e
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeElementInvertedListCursor.java
@@ -0,0 +1,280 @@
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import java.io.ByteArrayInputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
+
+public class FixedSizeElementInvertedListCursor implements IInvertedListCursor {
+
+    private final IBufferCache bufferCache;
+    private final int fileId;
+    private final int elementSize;
+    private int currentElementIx;
+    private int currentOff;
+    private int currentPageIx;
+
+    private int startPageId;
+    private int endPageId;
+    private int startOff;
+    private int numElements;
+
+    private final FixedSizeTupleReference tuple;
+    private ICachedPage[] pages = new ICachedPage[10];
+    private int[] elementIndexes = new int[10];
+
+    public FixedSizeElementInvertedListCursor(IBufferCache bufferCache, int fileId, ITypeTrait[] invListFields) {
+        this.bufferCache = bufferCache;
+        this.fileId = fileId;
+        this.currentElementIx = 0;
+        this.currentPageIx = 0;
+
+        int tmp = 0;
+        for (int i = 0; i < invListFields.length; i++) {
+            tmp += invListFields[i].getStaticallyKnownDataLength();
+        }
+        elementSize = tmp;
+        this.currentOff = -elementSize;
+        this.tuple = new FixedSizeTupleReference(invListFields);
+    }
+
+    @Override
+    public boolean hasNext() {
+        if (currentElementIx < numElements)
+            return true;
+        else
+            return false;
+    }
+
+    @Override
+    public void next() {
+        if (currentOff + elementSize >= bufferCache.getPageSize()) {
+            currentPageIx++;
+            currentOff = 0;
+        } else {
+            currentOff += elementSize;
+        }
+
+        currentElementIx++;
+        tuple.reset(pages[currentPageIx].getBuffer().array(), currentOff);
+    }
+
+    @Override
+    public void pinPagesAsync() {
+        // TODO: implement
+    }
+
+    @Override
+    public void pinPagesSync() throws HyracksDataException {
+        int pix = 0;
+        for (int i = startPageId; i <= endPageId; i++) {
+            pages[pix] = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, i), false);
+            pages[pix].acquireReadLatch();
+            pix++;
+        }
+    }
+
+    @Override
+    public void unpinPages() throws HyracksDataException {
+        int numPages = endPageId - startPageId + 1;
+        for (int i = 0; i < numPages; i++) {
+            pages[i].releaseReadLatch();
+            bufferCache.unpin(pages[i]);
+        }
+    }
+
+    @Override
+    public void positionCursor(int elementIx) {
+        int numPages = endPageId - startPageId + 1;
+
+        currentPageIx = binarySearch(elementIndexes, 0, numPages, elementIx);
+        if (currentPageIx < 0) {
+            throw new IndexOutOfBoundsException("Requested index: " + elementIx + " from array with numElements: "
+                    + numElements);
+        }
+
+        if (currentPageIx == 0) {
+            currentOff = startOff + elementIx * elementSize;
+        } else {
+            int relativeElementIx = elementIx - elementIndexes[currentPageIx - 1] - 1;
+            currentOff = relativeElementIx * elementSize;
+        }
+
+        currentElementIx = elementIx;
+        tuple.reset(pages[currentPageIx].getBuffer().array(), currentOff);
+    }
+
+    @Override
+    public boolean containsKey(ITupleReference searchTuple, MultiComparator invListCmp) {
+        int mid;
+        int begin = 0;
+        int end = numElements - 1;
+
+        while (begin <= end) {
+            mid = (begin + end) / 2;
+            positionCursor(mid);
+            int cmp = invListCmp.compare(searchTuple, tuple);
+            if (cmp < 0) {
+                end = mid - 1;
+            } else if (cmp > 0) {
+                begin = mid + 1;
+            } else {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    @Override
+    public void reset(int startPageId, int endPageId, int startOff, int numElements) {
+        this.startPageId = startPageId;
+        this.endPageId = endPageId;
+        this.startOff = startOff;
+        this.numElements = numElements;
+        this.currentElementIx = 0;
+        this.currentPageIx = 0;
+        this.currentOff = startOff - elementSize;
+
+        int numPages = endPageId - startPageId + 1;
+        if (numPages > pages.length) {
+            pages = new ICachedPage[endPageId - startPageId + 1];
+            elementIndexes = new int[endPageId - startPageId + 1];
+        }
+
+        // fill elementIndexes
+        // first page
+        int cumulElements = (bufferCache.getPageSize() - startOff) / elementSize;
+        elementIndexes[0] = cumulElements - 1;
+
+        // middle, full pages
+        for (int i = 1; i < numPages - 1; i++) {
+            elementIndexes[i] = elementIndexes[i - 1] + (bufferCache.getPageSize() / elementSize);
+        }
+
+        // last page
+        elementIndexes[numPages - 1] = numElements - 1;
+    }
+
+    @Override
+    public String printInvList(ISerializerDeserializer[] serdes) throws HyracksDataException {
+        int oldCurrentOff = currentOff;
+        int oldCurrentPageId = currentPageIx;
+        int oldCurrentElementIx = currentElementIx;
+
+        currentOff = startOff - elementSize;
+        currentPageIx = 0;
+        currentElementIx = 0;
+
+        StringBuilder strBuilder = new StringBuilder();
+
+        int count = 0;
+        while (hasNext()) {
+            next();
+            count++;
+            for (int i = 0; i < tuple.getFieldCount(); i++) {
+                ByteArrayInputStream inStream = new ByteArrayInputStream(tuple.getFieldData(i), tuple.getFieldStart(i),
+                        tuple.getFieldLength(i));
+                DataInput dataIn = new DataInputStream(inStream);
+                Object o = serdes[i].deserialize(dataIn);
+                strBuilder.append(o.toString());
+                if (i + 1 < tuple.getFieldCount())
+                    strBuilder.append(",");
+            }
+            strBuilder.append(" ");
+        }
+
+        // reset previous state
+        currentOff = oldCurrentOff;
+        currentPageIx = oldCurrentPageId;
+        currentElementIx = oldCurrentElementIx;
+
+        return strBuilder.toString();
+    }
+
+    public String printCurrentElement(ISerializerDeserializer[] serdes) throws HyracksDataException {
+        StringBuilder strBuilder = new StringBuilder();
+        for (int i = 0; i < tuple.getFieldCount(); i++) {
+            ByteArrayInputStream inStream = new ByteArrayInputStream(tuple.getFieldData(i), tuple.getFieldStart(i),
+                    tuple.getFieldLength(i));
+            DataInput dataIn = new DataInputStream(inStream);
+            Object o = serdes[i].deserialize(dataIn);
+            strBuilder.append(o.toString());
+            if (i + 1 < tuple.getFieldCount())
+                strBuilder.append(",");
+        }
+        return strBuilder.toString();
+    }
+
+    private int binarySearch(int[] arr, int arrStart, int arrLength, int key) {
+        int mid;
+        int begin = arrStart;
+        int end = arrStart + arrLength - 1;
+
+        while (begin <= end) {
+            mid = (begin + end) / 2;
+            int cmp = (key - arr[mid]);
+            if (cmp < 0) {
+                end = mid - 1;
+            } else if (cmp > 0) {
+                begin = mid + 1;
+            } else {
+                return mid;
+            }
+        }
+
+        if (begin > arr.length - 1)
+            return -1;
+        if (key < arr[begin])
+            return begin;
+        else
+            return -1;
+    }
+
+    @Override
+    public int compareTo(IInvertedListCursor invListCursor) {
+        return numElements - invListCursor.getNumElements();
+    }
+
+    @Override
+    public int getEndPageId() {
+        return endPageId;
+    }
+
+    @Override
+    public int getNumElements() {
+        return numElements;
+    }
+
+    @Override
+    public int getStartOff() {
+        return startOff;
+    }
+
+    @Override
+    public int getStartPageId() {
+        return startPageId;
+    }
+
+    public int getOffset() {
+        return currentOff;
+    }
+
+    public ICachedPage getPage() {
+        return pages[currentPageIx];
+    }
+
+    @Override
+    public ITupleReference getTuple() {
+        return tuple;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeFrameTupleAccessor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeFrameTupleAccessor.java
new file mode 100644
index 0000000..9858eb0
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeFrameTupleAccessor.java
@@ -0,0 +1,98 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.comm.FrameHelper;
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+
+public class FixedSizeFrameTupleAccessor implements IFrameTupleAccessor {
+
+    private final int frameSize;
+    private ByteBuffer buffer;
+
+    private final ITypeTrait[] fields;
+    private final int[] fieldStartOffsets;
+    private final int tupleSize;
+
+    public FixedSizeFrameTupleAccessor(int frameSize, ITypeTrait[] fields) {
+        this.frameSize = frameSize;
+        this.fields = fields;
+        this.fieldStartOffsets = new int[fields.length];
+        this.fieldStartOffsets[0] = 0;
+        for (int i = 1; i < fields.length; i++) {
+            fieldStartOffsets[i] = fieldStartOffsets[i - 1] + fields[i - 1].getStaticallyKnownDataLength();
+        }
+
+        int tmp = 0;
+        for (int i = 0; i < fields.length; i++) {
+            tmp += fields[i].getStaticallyKnownDataLength();
+        }
+        tupleSize = tmp;
+    }
+
+    @Override
+    public ByteBuffer getBuffer() {
+        return buffer;
+    }
+
+    @Override
+    public int getFieldCount() {
+        return fields.length;
+    }
+
+    @Override
+    public int getFieldEndOffset(int tupleIndex, int fIdx) {
+        return getTupleStartOffset(tupleIndex) + fieldStartOffsets[fIdx] + fields[fIdx].getStaticallyKnownDataLength();
+    }
+
+    @Override
+    public int getFieldLength(int tupleIndex, int fIdx) {
+        return fields[fIdx].getStaticallyKnownDataLength();
+    }
+
+    @Override
+    public int getFieldSlotsLength() {
+        return 0;
+    }
+
+    @Override
+    public int getFieldStartOffset(int tupleIndex, int fIdx) {
+        return tupleIndex * tupleSize + fieldStartOffsets[fIdx];
+    }
+
+    @Override
+    public int getTupleCount() {
+        return buffer.getInt(FrameHelper.getTupleCountOffset(frameSize));
+    }
+
+    @Override
+    public int getTupleEndOffset(int tupleIndex) {
+        return getFieldEndOffset(tupleIndex, fields.length - 1);
+    }
+
+    @Override
+    public int getTupleStartOffset(int tupleIndex) {
+        return tupleIndex * tupleSize;
+    }
+
+    @Override
+    public void reset(ByteBuffer buffer) {
+        this.buffer = buffer;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeFrameTupleAppender.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeFrameTupleAppender.java
new file mode 100644
index 0000000..edc2304
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeFrameTupleAppender.java
@@ -0,0 +1,127 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.comm.FrameHelper;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+
+public class FixedSizeFrameTupleAppender {
+
+    private static final int TUPLE_COUNT_SIZE = 4;
+    private final int frameSize;
+    private final int tupleSize;
+    private ByteBuffer buffer;
+    private int tupleCount;
+    private int tupleDataEndOffset;
+
+    public FixedSizeFrameTupleAppender(int frameSize, ITypeTrait[] fields) {
+        this.frameSize = frameSize;
+        int tmp = 0;
+        for (int i = 0; i < fields.length; i++) {
+            tmp += fields[i].getStaticallyKnownDataLength();
+        }
+        tupleSize = tmp;
+    }
+
+    public void reset(ByteBuffer buffer, boolean clear) {
+        this.buffer = buffer;
+        if (clear) {
+            buffer.putInt(FrameHelper.getTupleCountOffset(frameSize), 0);
+            tupleCount = 0;
+            tupleDataEndOffset = 0;
+        }
+    }
+
+    public boolean append(byte[] bytes, int offset) {
+        if (tupleDataEndOffset + tupleSize + TUPLE_COUNT_SIZE <= frameSize) {
+            System.arraycopy(bytes, offset, buffer.array(), tupleDataEndOffset, tupleSize);
+            tupleDataEndOffset += tupleSize;
+            tupleCount++;
+            return true;
+        }
+        return false;
+    }
+
+    public boolean append(byte[] bytes, int offset, int length) {
+        if (tupleDataEndOffset + length + TUPLE_COUNT_SIZE <= frameSize) {
+            System.arraycopy(bytes, offset, buffer.array(), tupleDataEndOffset, length);
+            tupleDataEndOffset += length;
+            return true;
+        }
+        return false;
+    }
+
+    public boolean append(int fieldValue) {
+        if (tupleDataEndOffset + 4 + TUPLE_COUNT_SIZE <= frameSize) {
+            buffer.putInt(tupleDataEndOffset, fieldValue);
+            tupleDataEndOffset += 4;
+            tupleCount++;
+            return true;
+        }
+        return false;
+    }
+
+    public boolean append(long fieldValue) {
+        if (tupleDataEndOffset + 8 + TUPLE_COUNT_SIZE <= frameSize) {
+            buffer.putLong(tupleDataEndOffset, fieldValue);
+            tupleDataEndOffset += 8;
+            tupleCount++;
+            return true;
+        }
+        return false;
+    }
+
+    public boolean append(char fieldValue) {
+        if (tupleDataEndOffset + 2 + TUPLE_COUNT_SIZE <= frameSize) {
+            buffer.putLong(tupleDataEndOffset, fieldValue);
+            tupleDataEndOffset += 2;
+            tupleCount++;
+            return true;
+        }
+        return false;
+    }
+
+    public boolean append(byte fieldValue) {
+        if (tupleDataEndOffset + 1 + TUPLE_COUNT_SIZE <= frameSize) {
+            buffer.put(tupleDataEndOffset, fieldValue);
+            tupleDataEndOffset += 1;
+            tupleCount++;
+            return true;
+        }
+        return false;
+    }
+
+    // returns true if an entire tuple fits
+    // returns false otherwise
+    public boolean hasSpace() {
+        return tupleDataEndOffset + tupleSize + TUPLE_COUNT_SIZE <= frameSize;
+    }
+
+    public void incrementTupleCount(int count) {
+        buffer.putInt(FrameHelper.getTupleCountOffset(frameSize),
+                buffer.getInt(FrameHelper.getTupleCountOffset(frameSize)) + count);
+    }
+
+    public int getTupleCount() {
+        return tupleCount;
+    }
+
+    public ByteBuffer getBuffer() {
+        return buffer;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeTupleReference.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeTupleReference.java
new file mode 100644
index 0000000..248b81e
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/FixedSizeTupleReference.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+
+public class FixedSizeTupleReference implements ITupleReference {
+
+    private final ITypeTrait[] typeTraits;
+    private final int[] fieldStartOffsets;
+    private byte[] data;
+    private int startOff;
+
+    public FixedSizeTupleReference(ITypeTrait[] typeTraits) {
+        this.typeTraits = typeTraits;
+        this.fieldStartOffsets = new int[typeTraits.length];
+        this.fieldStartOffsets[0] = 0;
+        for (int i = 1; i < typeTraits.length; i++) {
+            fieldStartOffsets[i] = fieldStartOffsets[i - 1] + typeTraits[i - 1].getStaticallyKnownDataLength();
+        }
+    }
+
+    public void reset(byte[] data, int startOff) {
+        this.data = data;
+        this.startOff = startOff;
+    }
+
+    @Override
+    public int getFieldCount() {
+        return typeTraits.length;
+    }
+
+    @Override
+    public byte[] getFieldData(int fIdx) {
+        return data;
+    }
+
+    @Override
+    public int getFieldLength(int fIdx) {
+        return typeTraits[fIdx].getStaticallyKnownDataLength();
+    }
+
+    @Override
+    public int getFieldStart(int fIdx) {
+        return startOff + fieldStartOffsets[fIdx];
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndex.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndex.java
new file mode 100644
index 0000000..9eab110
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndex.java
@@ -0,0 +1,289 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ByteArrayAccessibleOutputStream;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.FrameTupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
+import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexBulkLoadContext;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
+
+/**
+ * An inverted index consists of two files: 1. a file storing (paginated)
+ * inverted lists 2. a BTree-file mapping from tokens to inverted lists
+ * 
+ * Implemented features: bulk loading and searching (based on T-Occurrence) Not
+ * implemented features: updates (insert/update/delete) Limitations: a query
+ * cannot exceed the size of a Hyracks frame
+ */
+public class InvertedIndex {
+
+    private BTree btree;
+    private int rootPageId = 0;
+    private IBufferCache bufferCache;
+    private int fileId;
+    private final MultiComparator invListCmp;
+    private final int numTokenFields;
+    private final int numInvListKeys;
+
+    public InvertedIndex(IBufferCache bufferCache, BTree btree, MultiComparator invListCmp) {
+        this.bufferCache = bufferCache;
+        this.btree = btree;
+        this.invListCmp = invListCmp;
+        this.numTokenFields = btree.getMultiComparator().getKeyFieldCount();
+        this.numInvListKeys = invListCmp.getKeyFieldCount();
+    }
+
+    public void open(int fileId) {
+        this.fileId = fileId;
+    }
+
+    public void close() {
+        this.fileId = -1;
+    }
+
+    public BulkLoadContext beginBulkLoad(IInvertedListBuilder invListBuilder, int hyracksFrameSize,
+            float btreeFillFactor) throws HyracksDataException {
+        BulkLoadContext ctx = new BulkLoadContext(invListBuilder, hyracksFrameSize, btreeFillFactor);
+        ctx.init(rootPageId, fileId);
+        return ctx;
+    }
+
+    // ASSUMPTIONS:
+    // the first btree.getMultiComparator().getKeyFieldCount() fields in tuple
+    // are btree keys (e.g., a string token)
+    // the next invListCmp.getKeyFieldCount() fields in tuple are keys of the
+    // inverted list (e.g., primary key)
+    // key fields of inverted list are fixed size
+    public void bulkLoadAddTuple(BulkLoadContext ctx, ITupleReference tuple) throws HyracksDataException {
+
+        // first inverted list, copy token to baaos and start new list
+        if (ctx.currentInvListTokenBaaos.size() == 0) {
+            ctx.currentInvListStartPageId = ctx.currentPageId;
+            ctx.currentInvListStartOffset = ctx.invListBuilder.getPos();
+
+            // remember current token
+            ctx.currentInvListTokenBaaos.reset();
+            for (int i = 0; i < numTokenFields; i++) {
+                ctx.currentInvListTokenBaaos.write(tuple.getFieldData(i), tuple.getFieldStart(i),
+                        tuple.getFieldLength(i));
+            }
+
+            if (!ctx.invListBuilder.startNewList(tuple, numTokenFields)) {
+                ctx.pinNextPage();
+                ctx.invListBuilder.setTargetBuffer(ctx.currentPage.getBuffer().array(), 0);
+                if (!ctx.invListBuilder.startNewList(tuple, numTokenFields)) {
+                    throw new IllegalStateException("Failed to create first inverted list.");
+                }
+            }
+        }
+
+        // create new inverted list?
+        ctx.currentInvListToken.reset(ctx.currentInvListTokenBaaos.getByteArray(), 0);
+        if (ctx.tokenCmp.compare(tuple, ctx.currentInvListToken) != 0) {
+
+            // create entry in btree for last inverted list
+            createAndInsertBTreeTuple(ctx);
+
+            // remember new token
+            ctx.currentInvListTokenBaaos.reset();
+            for (int i = 0; i < numTokenFields; i++) {
+                ctx.currentInvListTokenBaaos.write(tuple.getFieldData(i), tuple.getFieldStart(i),
+                        tuple.getFieldLength(i));
+            }
+
+            // start new list
+            if (!ctx.invListBuilder.startNewList(tuple, numTokenFields)) {
+                ctx.pinNextPage();
+                ctx.invListBuilder.setTargetBuffer(ctx.currentPage.getBuffer().array(), 0);
+                if (!ctx.invListBuilder.startNewList(tuple, numTokenFields)) {
+                    throw new IllegalStateException("Failed to start new inverted list after switching to a new page.");
+                }
+            }
+
+            ctx.currentInvListStartPageId = ctx.currentPageId;
+            ctx.currentInvListStartOffset = ctx.invListBuilder.getPos();
+        }
+
+        // append to current inverted list
+        if (!ctx.invListBuilder.appendElement(tuple, numTokenFields, numInvListKeys)) {
+            ctx.pinNextPage();
+            ctx.invListBuilder.setTargetBuffer(ctx.currentPage.getBuffer().array(), 0);
+            if (!ctx.invListBuilder.appendElement(tuple, numTokenFields, numInvListKeys)) {
+                throw new IllegalStateException(
+                        "Failed to append element to inverted list after switching to a new page.");
+            }
+        }
+    }
+
+    public boolean openCursor(ITreeIndexCursor btreeCursor, RangePredicate btreePred, BTreeOpContext btreeOpCtx,
+            IInvertedListCursor invListCursor) throws Exception {
+        btree.search(btreeCursor, btreePred, btreeOpCtx);
+
+        boolean ret = false;
+        if (btreeCursor.hasNext()) {
+
+            btreeCursor.next();
+            ITupleReference frameTuple = btreeCursor.getTuple();
+
+            // hardcoded mapping of btree fields
+            int startPageId = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(1),
+                    frameTuple.getFieldStart(1));
+            int endPageId = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(2),
+                    frameTuple.getFieldStart(2));
+            int startOff = IntegerSerializerDeserializer
+                    .getInt(frameTuple.getFieldData(3), frameTuple.getFieldStart(3));
+            int numElements = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(4),
+                    frameTuple.getFieldStart(4));
+
+            invListCursor.reset(startPageId, endPageId, startOff, numElements);
+            ret = true;
+        } else {
+            invListCursor.reset(0, 0, 0, 0);
+        }
+
+        btreeCursor.close();
+        btreeCursor.reset();
+
+        return ret;
+    }
+
+    public void createAndInsertBTreeTuple(BulkLoadContext ctx) throws HyracksDataException {
+        // build tuple
+        ctx.btreeTupleBuilder.reset();
+        ctx.btreeTupleBuilder.addField(ctx.currentInvListTokenBaaos.getByteArray(), 0,
+                ctx.currentInvListTokenBaaos.size());
+        ctx.btreeTupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, ctx.currentInvListStartPageId);
+        ctx.btreeTupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, ctx.currentPageId);
+        ctx.btreeTupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, ctx.currentInvListStartOffset);
+        ctx.btreeTupleBuilder.addField(IntegerSerializerDeserializer.INSTANCE, ctx.invListBuilder.getListSize());
+
+        // append to buffer
+        ctx.btreeTupleAppender.reset(ctx.btreeTupleBuffer, true);
+        ctx.btreeTupleAppender.append(ctx.btreeTupleBuilder.getFieldEndOffsets(), ctx.btreeTupleBuilder.getByteArray(),
+                0, ctx.btreeTupleBuilder.getSize());
+
+        // reset tuple reference
+        ctx.btreeFrameTupleReference.reset(ctx.btreeFrameTupleAccessor, 0);
+
+        btree.bulkLoadAddTuple(ctx.btreeBulkLoadCtx, ctx.btreeFrameTupleReference);
+    }
+
+    public void endBulkLoad(BulkLoadContext ctx) throws HyracksDataException {
+        // create entry in btree for last inverted list
+        createAndInsertBTreeTuple(ctx);
+        btree.endBulkLoad(ctx.btreeBulkLoadCtx);
+        ctx.deinit();
+    }
+
+    public IBufferCache getBufferCache() {
+        return bufferCache;
+    }
+
+    public int getInvListsFileId() {
+        return fileId;
+    }
+
+    public MultiComparator getInvListElementCmp() {
+        return invListCmp;
+    }
+
+    public BTree getBTree() {
+        return btree;
+    }
+
+    public final class BulkLoadContext {
+        private final ByteBuffer btreeTupleBuffer;
+        private final ArrayTupleBuilder btreeTupleBuilder;
+        private final FrameTupleAppender btreeTupleAppender;
+        private final FrameTupleAccessor btreeFrameTupleAccessor;
+        private final FrameTupleReference btreeFrameTupleReference = new FrameTupleReference();
+        private final float btreeFillFactor;
+        private IIndexBulkLoadContext btreeBulkLoadCtx;
+
+        private int currentInvListStartPageId;
+        private int currentInvListStartOffset;
+        private final ByteArrayAccessibleOutputStream currentInvListTokenBaaos = new ByteArrayAccessibleOutputStream();
+        private final FixedSizeTupleReference currentInvListToken = new FixedSizeTupleReference(
+                invListCmp.getTypeTraits());
+
+        private int currentPageId;
+        private ICachedPage currentPage;
+        private final IInvertedListBuilder invListBuilder;
+        private final MultiComparator tokenCmp;
+
+        public BulkLoadContext(IInvertedListBuilder invListBuilder, int hyracksFrameSize, float btreeFillFactor) {
+            this.invListBuilder = invListBuilder;
+            this.tokenCmp = btree.getMultiComparator();
+            this.btreeTupleBuffer = ByteBuffer.allocate(hyracksFrameSize);
+            this.btreeTupleBuilder = new ArrayTupleBuilder(tokenCmp.getFieldCount());
+            this.btreeTupleAppender = new FrameTupleAppender(hyracksFrameSize);
+            // TODO: serde never used, only need correct number of fields
+            // tuple contains (token, start page, end page, start offset, num
+            // elements)
+            RecordDescriptor recDesc = new RecordDescriptor(new ISerializerDeserializer[] {
+                    IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
+                    IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE,
+                    IntegerSerializerDeserializer.INSTANCE });
+            this.btreeFrameTupleAccessor = new FrameTupleAccessor(hyracksFrameSize, recDesc);
+            this.btreeFillFactor = btreeFillFactor;
+        }
+
+        public void init(int startPageId, int fileId) throws HyracksDataException {
+            btreeBulkLoadCtx = btree.beginBulkLoad(BTree.DEFAULT_FILL_FACTOR,
+                    btree.getLeafFrameFactory().createFrame(), btree.getInteriorFrameFactory().createFrame(), btree
+                            .getFreePageManager().getMetaDataFrameFactory().createFrame());
+            currentPageId = startPageId;
+            currentPage = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, currentPageId), true);
+            currentPage.acquireWriteLatch();
+            invListBuilder.setTargetBuffer(currentPage.getBuffer().array(), 0);
+            btreeFrameTupleAccessor.reset(btreeTupleBuffer);
+        }
+
+        public void deinit() throws HyracksDataException {
+            if (currentPage != null) {
+                currentPage.releaseWriteLatch();
+                bufferCache.unpin(currentPage);
+            }
+        }
+
+        public void pinNextPage() throws HyracksDataException {
+            currentPage.releaseWriteLatch();
+            bufferCache.unpin(currentPage);
+            currentPageId++;
+            currentPage = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, currentPageId), true);
+            currentPage.acquireWriteLatch();
+        }
+    };
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IBinaryTokenizerFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndexException.java
similarity index 72%
copy from hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IBinaryTokenizerFactory.java
copy to hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndexException.java
index 7e91fd4..494ac0c 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/api/IBinaryTokenizerFactory.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/InvertedIndexException.java
@@ -13,10 +13,12 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.invertedindex.api;
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
 
-import java.io.Serializable;
+public class InvertedIndexException extends Exception {
+    private static final long serialVersionUID = 1L;
 
-public interface IBinaryTokenizerFactory extends Serializable {
-    public IBinaryTokenizer createBinaryTokenizer();
+    public InvertedIndexException(String msg) {
+        super(msg);
+    }
 }
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/ListResultCursor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/ListResultCursor.java
deleted file mode 100644
index adc5221..0000000
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/ListResultCursor.java
+++ /dev/null
@@ -1,57 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
-
-import java.nio.ByteBuffer;
-import java.util.List;
-
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexResultCursor;
-
-public class ListResultCursor implements IInvertedIndexResultCursor {
-
-    private List<ByteBuffer> resultBuffers;
-    private int numResultBuffers;
-    private int currentPos = 0;
-
-    public void setResults(List<ByteBuffer> resultBuffers, int numResultBuffers) {
-        this.resultBuffers = resultBuffers;
-        this.numResultBuffers = numResultBuffers;
-        reset();
-    }
-
-    @Override
-    public boolean hasNext() {
-        if (currentPos + 1 < numResultBuffers)
-            return true;
-        else
-            return false;
-    }
-
-    @Override
-    public void next() {
-        currentPos++;
-    }
-
-    @Override
-    public ByteBuffer getBuffer() {
-        return resultBuffers.get(currentPos);
-    }
-
-    @Override
-    public void reset() {
-        currentPos = -1;
-    }
-}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrameFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/OccurrenceThresholdPanicException.java
similarity index 69%
copy from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrameFactory.java
copy to hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/OccurrenceThresholdPanicException.java
index 50733de..b0e737c 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeLeafFrameFactory.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/OccurrenceThresholdPanicException.java
@@ -13,10 +13,12 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
 
-import java.io.Serializable;
+public class OccurrenceThresholdPanicException extends InvertedIndexException {
+    private static final long serialVersionUID = 1L;
 
-public interface IBTreeLeafFrameFactory extends Serializable {
-    public IBTreeLeafFrame getFrame();
-}
\ No newline at end of file
+    public OccurrenceThresholdPanicException(String msg) {
+        super(msg);
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/SearchResultCursor.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/SearchResultCursor.java
new file mode 100644
index 0000000..5a7230c
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/SearchResultCursor.java
@@ -0,0 +1,76 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import java.nio.ByteBuffer;
+import java.util.List;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexResultCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexSearcher;
+
+public class SearchResultCursor implements IInvertedIndexResultCursor {
+
+    private List<ByteBuffer> resultBuffers;
+    private IFrameTupleAccessor fta;
+    private FixedSizeTupleReference resultTuple;
+    private int numResultBuffers;
+    private int currentBufferIndex = 0;
+    private int tupleIndex = 0;
+
+    public SearchResultCursor(IFrameTupleAccessor fta, ITupleReference resultTuple) {
+        this.fta = fta;
+        this.resultTuple = (FixedSizeTupleReference) resultTuple;
+    }
+
+    @Override
+    public boolean hasNext() {
+        if (currentBufferIndex < numResultBuffers && tupleIndex < fta.getTupleCount())
+            return true;
+        else
+            return false;
+    }
+
+    @Override
+    public void next() {
+        resultTuple.reset(fta.getBuffer().array(), fta.getTupleStartOffset(tupleIndex));
+        tupleIndex++;
+        if (tupleIndex >= fta.getTupleCount()) {
+            if (currentBufferIndex + 1 < numResultBuffers) {
+                currentBufferIndex++;
+                fta.reset(resultBuffers.get(currentBufferIndex));
+                tupleIndex = 0;
+            }
+        }
+    }
+
+    @Override
+    public ITupleReference getTuple() {
+        return resultTuple;
+    }
+
+    @Override
+    public void reset(IInvertedIndexSearcher invIndexSearcher) {
+        currentBufferIndex = 0;
+        tupleIndex = 0;
+        resultBuffers = invIndexSearcher.getResultBuffers();
+        numResultBuffers = invIndexSearcher.getNumValidResultBuffers();
+        if (numResultBuffers > 0) {
+            fta.reset(resultBuffers.get(0));
+        }
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/SimpleConjunctiveSearcher.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/SimpleConjunctiveSearcher.java
deleted file mode 100644
index 6ad5a9c..0000000
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/SimpleConjunctiveSearcher.java
+++ /dev/null
@@ -1,294 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
-
-import java.io.DataOutput;
-import java.io.IOException;
-import java.nio.ByteBuffer;
-import java.util.ArrayList;
-import java.util.List;
-
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
-import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
-import edu.uci.ics.hyracks.dataflow.common.data.accessors.FrameTupleReference;
-import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
-import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeCursor;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
-import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
-import edu.uci.ics.hyracks.storage.am.btree.impls.RangeSearchCursor;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizer;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexResultCursor;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexSearcher;
-
-public class SimpleConjunctiveSearcher implements IInvertedIndexSearcher {
-
-    private final int numKeyFields;
-    private final int numValueFields;
-
-    private final IBinaryComparator[] keyCmps;
-    private final IBinaryComparator[] valueCmps;
-
-    private final BTree btree;
-    private final IHyracksStageletContext ctx;
-    private final ArrayTupleBuilder resultTupleBuilder;
-    private final FrameTupleAppender resultTupleAppender;
-    private final FrameTupleAccessor resultFrameAccessor;
-
-    private List<ByteBuffer> newResultBuffers = new ArrayList<ByteBuffer>();
-    private List<ByteBuffer> prevResultBuffers = new ArrayList<ByteBuffer>();
-    private List<ByteBuffer> swap = null;
-    private final ListResultCursor resultCursor = new ListResultCursor();
-    private int maxResultBufIdx = 0;
-
-    private final IBTreeLeafFrame leafFrame;
-    private final IBTreeInteriorFrame interiorFrame;
-    private final IBTreeCursor btreeCursor;
-    private final FrameTupleReference searchKey = new FrameTupleReference();
-    private final RangePredicate pred = new RangePredicate(true, null, null, true, true, null, null);
-
-    private final IBinaryTokenizer queryTokenizer;
-
-    public SimpleConjunctiveSearcher(IHyracksStageletContext ctx, BTree btree, RecordDescriptor btreeRecDesc,
-            IBinaryTokenizer queryTokenizer, int numKeyFields, int numValueFields) {
-        this.ctx = ctx;
-        this.btree = btree;
-        this.queryTokenizer = queryTokenizer;
-        this.numKeyFields = numKeyFields;
-        this.numValueFields = numValueFields;
-
-        leafFrame = btree.getLeafFrameFactory().getFrame();
-        interiorFrame = btree.getInteriorFrameFactory().getFrame();
-        btreeCursor = new RangeSearchCursor(leafFrame);
-        resultTupleAppender = new FrameTupleAppender(ctx.getFrameSize());
-        resultTupleBuilder = new ArrayTupleBuilder(numValueFields);
-        newResultBuffers.add(ctx.allocateFrame());
-        prevResultBuffers.add(ctx.allocateFrame());
-
-        MultiComparator btreeCmp = btree.getMultiComparator();
-
-        keyCmps = new IBinaryComparator[numKeyFields];
-        for (int i = 0; i < numKeyFields; i++) {
-            keyCmps[i] = btreeCmp.getComparators()[i];
-        }
-
-        valueCmps = new IBinaryComparator[numValueFields];
-        for (int i = 0; i < numValueFields; i++) {
-            valueCmps[i] = btreeCmp.getComparators()[numKeyFields + i];
-        }
-
-        MultiComparator searchCmp = new MultiComparator(btreeCmp.getTypeTraits(), keyCmps);
-        pred.setLowKeyComparator(searchCmp);
-        pred.setHighKeyComparator(searchCmp);
-        pred.setLowKey(searchKey, true);
-        pred.setHighKey(searchKey, true);
-
-        ISerializerDeserializer[] valueSerde = new ISerializerDeserializer[numValueFields];
-        for (int i = 0; i < numValueFields; i++) {
-            valueSerde[i] = btreeRecDesc.getFields()[numKeyFields + i];
-
-        }
-        RecordDescriptor valueRecDesc = new RecordDescriptor(valueSerde);
-        resultFrameAccessor = new FrameTupleAccessor(ctx.getFrameSize(), valueRecDesc);
-    }
-
-    public void search(ITupleReference queryTuple, int queryFieldIndex) throws Exception {
-
-        // parse query, TODO: this parsing is too simple
-        RecordDescriptor queryTokenRecDesc = new RecordDescriptor(
-                new ISerializerDeserializer[] { UTF8StringSerializerDeserializer.INSTANCE });
-
-        ArrayTupleBuilder queryTokenBuilder = new ArrayTupleBuilder(queryTokenRecDesc.getFields().length);
-        DataOutput queryTokenDos = queryTokenBuilder.getDataOutput();
-        FrameTupleAppender queryTokenAppender = new FrameTupleAppender(ctx.getFrameSize());
-        ByteBuffer queryTokenFrame = ctx.allocateFrame();
-        queryTokenAppender.reset(queryTokenFrame, true);
-
-        queryTokenizer.reset(queryTuple.getFieldData(queryFieldIndex), queryTuple.getFieldStart(queryFieldIndex),
-                queryTuple.getFieldLength(queryFieldIndex));
-        while (queryTokenizer.hasNext()) {
-            queryTokenizer.next();
-
-            queryTokenBuilder.reset();
-            try {
-                queryTokenizer.writeToken(queryTokenDos);
-                queryTokenBuilder.addFieldEndOffset();
-            } catch (IOException e) {
-                throw new HyracksDataException(e);
-            }
-
-            // WARNING: assuming one frame is enough to hold all tokens
-            queryTokenAppender.append(queryTokenBuilder.getFieldEndOffsets(), queryTokenBuilder.getByteArray(), 0,
-                    queryTokenBuilder.getSize());
-        }
-
-        FrameTupleAccessor queryTokenAccessor = new FrameTupleAccessor(ctx.getFrameSize(), queryTokenRecDesc);
-        queryTokenAccessor.reset(queryTokenFrame);
-        int numQueryTokens = queryTokenAccessor.getTupleCount();
-
-        maxResultBufIdx = 0;
-
-        BTreeOpContext opCtx = btree.createOpContext(BTreeOp.BTO_SEARCH, leafFrame, interiorFrame, null);
-
-        resultTupleAppender.reset(newResultBuffers.get(0), true);
-        try {
-            // append first inverted list to temporary results
-            searchKey.reset(queryTokenAccessor, 0);
-            btree.search(btreeCursor, pred, opCtx);
-            while (btreeCursor.hasNext()) {
-                btreeCursor.next();
-                maxResultBufIdx = appendTupleToNewResults(btreeCursor, maxResultBufIdx);
-            }
-            btreeCursor.close();
-            btreeCursor.reset();
-        } catch (Exception e) {
-            throw new HyracksDataException(e);
-        }
-
-        resultFrameAccessor.reset(newResultBuffers.get(0));
-
-        // intersect temporary results with remaining inverted lists
-        for (int i = 1; i < numQueryTokens; i++) {
-            swap = prevResultBuffers;
-            prevResultBuffers = newResultBuffers;
-            newResultBuffers = swap;
-            try {
-                searchKey.reset(queryTokenAccessor, i);
-                btree.search(btreeCursor, pred, opCtx);
-                maxResultBufIdx = intersectList(btreeCursor, prevResultBuffers, maxResultBufIdx, newResultBuffers);
-            } catch (Exception e) {
-                throw new HyracksDataException(e);
-            }
-            btreeCursor.close();
-            btreeCursor.reset();
-        }
-    }
-
-    private int appendTupleToNewResults(IBTreeCursor btreeCursor, int newBufIdx) throws IOException {
-        ByteBuffer newCurrentBuffer = newResultBuffers.get(newBufIdx);
-
-        ITupleReference tuple = btreeCursor.getTuple();
-        resultTupleBuilder.reset();
-        DataOutput dos = resultTupleBuilder.getDataOutput();
-        for (int i = 0; i < numValueFields; i++) {
-            int fIdx = numKeyFields + i;
-            dos.write(tuple.getFieldData(fIdx), tuple.getFieldStart(fIdx), tuple.getFieldLength(fIdx));
-            resultTupleBuilder.addFieldEndOffset();
-        }
-
-        if (!resultTupleAppender.append(resultTupleBuilder.getFieldEndOffsets(), resultTupleBuilder.getByteArray(), 0,
-                resultTupleBuilder.getSize())) {
-            newBufIdx++;
-            if (newBufIdx >= newResultBuffers.size()) {
-                newResultBuffers.add(ctx.allocateFrame());
-            }
-            newCurrentBuffer = newResultBuffers.get(newBufIdx);
-            resultTupleAppender.reset(newCurrentBuffer, true);
-            if (!resultTupleAppender.append(resultTupleBuilder.getFieldEndOffsets(), resultTupleBuilder.getByteArray(),
-                    0, resultTupleBuilder.getSize())) {
-                throw new IllegalStateException();
-            }
-        }
-
-        return newBufIdx;
-    }
-
-    private int intersectList(IBTreeCursor btreeCursor, List<ByteBuffer> prevResultBuffers, int maxPrevBufIdx,
-            List<ByteBuffer> newResultBuffers) throws IOException, Exception {
-
-        int newBufIdx = 0;
-        ByteBuffer newCurrentBuffer = newResultBuffers.get(0);
-
-        int prevBufIdx = 0;
-        ByteBuffer prevCurrentBuffer = prevResultBuffers.get(0);
-
-        resultTupleBuilder.reset();
-        resultTupleAppender.reset(newCurrentBuffer, true);
-        resultFrameAccessor.reset(prevCurrentBuffer);
-
-        // WARNING: not very efficient but good enough for the first cut
-        boolean advanceCursor = true;
-        boolean advancePrevResult = false;
-        int resultTidx = 0;
-
-        while ((!advanceCursor || btreeCursor.hasNext()) && prevBufIdx <= maxPrevBufIdx
-                && resultTidx < resultFrameAccessor.getTupleCount()) {
-
-            if (advanceCursor)
-                btreeCursor.next();
-            ITupleReference tuple = btreeCursor.getTuple();
-
-            int cmp = 0;
-            for (int i = 0; i < valueCmps.length; i++) {
-                int tupleFidx = numKeyFields + i;
-                cmp = valueCmps[i].compare(tuple.getFieldData(tupleFidx), tuple.getFieldStart(tupleFidx),
-                        tuple.getFieldLength(tupleFidx), resultFrameAccessor.getBuffer().array(),
-                        resultFrameAccessor.getTupleStartOffset(resultTidx) + resultFrameAccessor.getFieldSlotsLength()
-                                + resultFrameAccessor.getFieldStartOffset(resultTidx, i),
-                        resultFrameAccessor.getFieldLength(resultTidx, i));
-                if (cmp != 0)
-                    break;
-            }
-
-            // match found
-            if (cmp == 0) {
-                newBufIdx = appendTupleToNewResults(btreeCursor, newBufIdx);
-
-                advanceCursor = true;
-                advancePrevResult = true;
-            } else {
-                if (cmp < 0) {
-                    advanceCursor = true;
-                    advancePrevResult = false;
-                } else {
-                    advanceCursor = false;
-                    advancePrevResult = true;
-                }
-            }
-
-            if (advancePrevResult) {
-                resultTidx++;
-                if (resultTidx >= resultFrameAccessor.getTupleCount()) {
-                    prevBufIdx++;
-                    if (prevBufIdx <= maxPrevBufIdx) {
-                        prevCurrentBuffer = prevResultBuffers.get(prevBufIdx);
-                        resultFrameAccessor.reset(prevCurrentBuffer);
-                        resultTidx = 0;
-                    }
-                }
-            }
-        }
-
-        return newBufIdx;
-    }
-
-    @Override
-    public IInvertedIndexResultCursor getResultCursor() {
-        resultCursor.setResults(newResultBuffers, maxResultBufIdx + 1);
-        return resultCursor;
-    }
-}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcher.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcher.java
new file mode 100644
index 0000000..d1fba3b
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcher.java
@@ -0,0 +1,543 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import java.io.DataOutput;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.List;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.dataflow.value.TypeTrait;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.FrameTupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeRangeSearchCursor;
+import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexResultCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexSearchModifier;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexSearcher;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizer;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IToken;
+
+public class TOccurrenceSearcher implements IInvertedIndexSearcher {
+
+    protected final IHyracksStageletContext ctx;
+    protected final FixedSizeFrameTupleAppender resultFrameTupleApp;
+    protected final FixedSizeFrameTupleAccessor resultFrameTupleAcc;
+    protected final FixedSizeTupleReference resultTuple;
+    protected final int invListKeyLength;
+    protected int currentNumResults;
+
+    protected List<ByteBuffer> newResultBuffers = new ArrayList<ByteBuffer>();
+    protected List<ByteBuffer> prevResultBuffers = new ArrayList<ByteBuffer>();
+    protected List<ByteBuffer> swap = null;
+    protected int maxResultBufIdx = 0;
+
+    protected final ITreeIndexFrame leafFrame;
+    protected final ITreeIndexFrame interiorFrame;
+    protected final ITreeIndexCursor btreeCursor;
+    protected final FrameTupleReference searchKey = new FrameTupleReference();
+    protected final RangePredicate btreePred = new RangePredicate(true, null, null, true, true, null, null);
+    protected final BTreeOpContext btreeOpCtx;
+
+    protected RecordDescriptor queryTokenRecDesc = new RecordDescriptor(
+            new ISerializerDeserializer[] { UTF8StringSerializerDeserializer.INSTANCE });
+    protected ArrayTupleBuilder queryTokenBuilder = new ArrayTupleBuilder(queryTokenRecDesc.getFields().length);
+    protected DataOutput queryTokenDos = queryTokenBuilder.getDataOutput();
+    protected FrameTupleAppender queryTokenAppender;
+    protected ByteBuffer queryTokenFrame;
+
+    protected final InvertedIndex invIndex;
+    protected final IBinaryTokenizer queryTokenizer;
+    protected final ITypeTrait[] invListFieldsWithCount;
+    protected int occurrenceThreshold;
+
+    protected final int cursorCacheSize = 10;
+    protected List<IInvertedListCursor> invListCursorCache = new ArrayList<IInvertedListCursor>(cursorCacheSize);
+    protected List<IInvertedListCursor> invListCursors = new ArrayList<IInvertedListCursor>(cursorCacheSize);
+
+    public TOccurrenceSearcher(IHyracksStageletContext ctx, InvertedIndex invIndex, IBinaryTokenizer queryTokenizer) {
+        this.ctx = ctx;
+        this.invIndex = invIndex;
+        this.queryTokenizer = queryTokenizer;
+
+        leafFrame = invIndex.getBTree().getLeafFrameFactory().createFrame();
+        interiorFrame = invIndex.getBTree().getInteriorFrameFactory().createFrame();
+
+        btreeCursor = new BTreeRangeSearchCursor((IBTreeLeafFrame) leafFrame);
+        ITypeTrait[] invListFields = invIndex.getInvListElementCmp().getTypeTraits();
+        invListFieldsWithCount = new TypeTrait[invListFields.length + 1];
+        int tmp = 0;
+        for (int i = 0; i < invListFields.length; i++) {
+            invListFieldsWithCount[i] = invListFields[i];
+            tmp += invListFields[i].getStaticallyKnownDataLength();
+        }
+        // using an integer for counting occurrences
+        invListFieldsWithCount[invListFields.length] = new TypeTrait(4);
+        invListKeyLength = tmp;
+
+        btreeOpCtx = invIndex.getBTree().createOpContext(IndexOp.SEARCH, leafFrame, interiorFrame, null);
+
+        resultFrameTupleApp = new FixedSizeFrameTupleAppender(ctx.getFrameSize(), invListFieldsWithCount);
+        resultFrameTupleAcc = new FixedSizeFrameTupleAccessor(ctx.getFrameSize(), invListFieldsWithCount);
+        resultTuple = new FixedSizeTupleReference(invListFieldsWithCount);
+        newResultBuffers.add(ctx.allocateFrame());
+        prevResultBuffers.add(ctx.allocateFrame());
+
+        MultiComparator searchCmp = invIndex.getBTree().getMultiComparator();
+        btreePred.setLowKeyComparator(searchCmp);
+        btreePred.setHighKeyComparator(searchCmp);
+        btreePred.setLowKey(searchKey, true);
+        btreePred.setHighKey(searchKey, true);
+
+        // pre-create cursor objects
+        for (int i = 0; i < cursorCacheSize; i++) {
+            invListCursorCache.add(new FixedSizeElementInvertedListCursor(invIndex.getBufferCache(), invIndex
+                    .getInvListsFileId(), invIndex.getInvListElementCmp().getTypeTraits()));
+        }
+
+        queryTokenAppender = new FrameTupleAppender(ctx.getFrameSize());
+        queryTokenFrame = ctx.allocateFrame();
+
+        currentNumResults = 0;
+    }
+
+    public void reset() {
+        for (ByteBuffer b : newResultBuffers) {
+            resultFrameTupleApp.reset(b, true);
+        }
+        for (ByteBuffer b : prevResultBuffers) {
+            resultFrameTupleApp.reset(b, true);
+        }
+        currentNumResults = 0;
+    }
+
+    public void search(IInvertedIndexResultCursor resultCursor, ITupleReference queryTuple, int queryFieldIndex,
+            IInvertedIndexSearchModifier searchModifier) throws Exception {
+
+        queryTokenAppender.reset(queryTokenFrame, true);
+        queryTokenizer.reset(queryTuple.getFieldData(queryFieldIndex), queryTuple.getFieldStart(queryFieldIndex),
+                queryTuple.getFieldLength(queryFieldIndex));
+
+        while (queryTokenizer.hasNext()) {
+            queryTokenizer.next();
+            queryTokenBuilder.reset();
+            try {
+                IToken token = queryTokenizer.getToken();
+                token.serializeToken(queryTokenDos);
+                queryTokenBuilder.addFieldEndOffset();
+                // WARNING: assuming one frame is big enough to hold all tokens
+                queryTokenAppender.append(queryTokenBuilder.getFieldEndOffsets(), queryTokenBuilder.getByteArray(), 0,
+                        queryTokenBuilder.getSize());
+            } catch (IOException e) {
+                throw new HyracksDataException(e);
+            }
+        }
+
+        FrameTupleAccessor queryTokenAccessor = new FrameTupleAccessor(ctx.getFrameSize(), queryTokenRecDesc);
+        queryTokenAccessor.reset(queryTokenFrame);
+        int numQueryTokens = queryTokenAccessor.getTupleCount();
+
+        // expand cursor cache if necessary
+        if (numQueryTokens > invListCursorCache.size()) {
+            int diff = numQueryTokens - invListCursorCache.size();
+            for (int i = 0; i < diff; i++) {
+                invListCursorCache.add(new FixedSizeElementInvertedListCursor(invIndex.getBufferCache(), invIndex
+                        .getInvListsFileId(), invIndex.getInvListElementCmp().getTypeTraits()));
+            }
+        }
+
+        invListCursors.clear();
+        for (int i = 0; i < numQueryTokens; i++) {
+            searchKey.reset(queryTokenAccessor, i);
+            invIndex.openCursor(btreeCursor, btreePred, btreeOpCtx, invListCursorCache.get(i));
+            invListCursors.add(invListCursorCache.get(i));
+        }
+
+        occurrenceThreshold = searchModifier.getOccurrenceThreshold(invListCursors);
+
+        // TODO: deal with panic cases properly
+        if (occurrenceThreshold <= 0) {
+            throw new OccurrenceThresholdPanicException("Merge Threshold is <= 0. Failing Search.");
+        }
+
+        int numPrefixLists = searchModifier.getPrefixLists(invListCursors);
+        maxResultBufIdx = mergePrefixLists(numPrefixLists, numQueryTokens);
+        maxResultBufIdx = mergeSuffixLists(numPrefixLists, numQueryTokens, maxResultBufIdx);
+
+        resultCursor.reset(this);
+    }
+
+    protected int mergePrefixLists(int numPrefixTokens, int numQueryTokens) throws IOException {
+        int maxPrevBufIdx = 0;
+        for (int i = 0; i < numPrefixTokens; i++) {
+            swap = prevResultBuffers;
+            prevResultBuffers = newResultBuffers;
+            newResultBuffers = swap;
+            currentNumResults = 0;
+
+            invListCursors.get(i).pinPagesSync();
+            maxPrevBufIdx = mergePrefixList(invListCursors.get(i), prevResultBuffers, maxPrevBufIdx, newResultBuffers);
+            invListCursors.get(i).unpinPages();
+        }
+        return maxPrevBufIdx;
+    }
+
+    protected int mergeSuffixLists(int numPrefixTokens, int numQueryTokens, int maxPrevBufIdx) throws IOException {
+        for (int i = numPrefixTokens; i < numQueryTokens; i++) {
+            swap = prevResultBuffers;
+            prevResultBuffers = newResultBuffers;
+            newResultBuffers = swap;
+
+            invListCursors.get(i).pinPagesSync();
+            int numInvListElements = invListCursors.get(i).getNumElements();
+            // should we binary search the next list or should we sort-merge it?
+            if (currentNumResults * Math.log(numInvListElements) < currentNumResults + numInvListElements) {
+                maxPrevBufIdx = mergeSuffixListProbe(invListCursors.get(i), prevResultBuffers, maxPrevBufIdx,
+                        newResultBuffers, i, numQueryTokens);
+            } else {
+                maxPrevBufIdx = mergeSuffixListScan(invListCursors.get(i), prevResultBuffers, maxPrevBufIdx,
+                        newResultBuffers, i, numQueryTokens);
+            }
+            invListCursors.get(i).unpinPages();
+        }
+        return maxPrevBufIdx;
+    }
+
+    protected int mergeSuffixListProbe(IInvertedListCursor invListCursor, List<ByteBuffer> prevResultBuffers,
+            int maxPrevBufIdx, List<ByteBuffer> newResultBuffers, int invListIx, int numQueryTokens) throws IOException {
+
+        int newBufIdx = 0;
+        ByteBuffer newCurrentBuffer = newResultBuffers.get(0);
+
+        int prevBufIdx = 0;
+        ByteBuffer prevCurrentBuffer = prevResultBuffers.get(0);
+
+        int resultTidx = 0;
+
+        currentNumResults = 0;
+
+        MultiComparator invListCmp = invIndex.getInvListElementCmp();
+
+        resultFrameTupleAcc.reset(prevCurrentBuffer);
+        resultFrameTupleApp.reset(newCurrentBuffer, true);
+
+        while (resultTidx < resultFrameTupleAcc.getTupleCount()) {
+
+            resultTuple.reset(prevCurrentBuffer.array(), resultFrameTupleAcc.getTupleStartOffset(resultTidx));
+            int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                    resultTuple.getFieldStart(resultTuple.getFieldCount() - 1));
+
+            if (invListCursor.containsKey(resultTuple, invListCmp)) {
+                count++;
+                newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+            } else {
+                if (count + numQueryTokens - invListIx > occurrenceThreshold) {
+                    newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+                }
+            }
+
+            resultTidx++;
+            if (resultTidx >= resultFrameTupleAcc.getTupleCount()) {
+                prevBufIdx++;
+                if (prevBufIdx <= maxPrevBufIdx) {
+                    prevCurrentBuffer = prevResultBuffers.get(prevBufIdx);
+                    resultFrameTupleAcc.reset(prevCurrentBuffer);
+                    resultTidx = 0;
+                }
+            }
+        }
+
+        return newBufIdx;
+    }
+
+    protected int mergeSuffixListScan(IInvertedListCursor invListCursor, List<ByteBuffer> prevResultBuffers,
+            int maxPrevBufIdx, List<ByteBuffer> newResultBuffers, int invListIx, int numQueryTokens) throws IOException {
+        int newBufIdx = 0;
+        ByteBuffer newCurrentBuffer = newResultBuffers.get(0);
+
+        int prevBufIdx = 0;
+        ByteBuffer prevCurrentBuffer = prevResultBuffers.get(0);
+
+        boolean advanceCursor = true;
+        boolean advancePrevResult = false;
+        int resultTidx = 0;
+
+        MultiComparator invListCmp = invIndex.getInvListElementCmp();
+
+        resultFrameTupleAcc.reset(prevCurrentBuffer);
+        resultFrameTupleApp.reset(newCurrentBuffer, true);
+
+        int invListTidx = 0;
+        int invListNumTuples = invListCursor.getNumElements();
+
+        if (invListCursor.hasNext())
+            invListCursor.next();
+
+        while (invListTidx < invListNumTuples && resultTidx < resultFrameTupleAcc.getTupleCount()) {
+
+            ITupleReference invListTuple = invListCursor.getTuple();
+
+            resultTuple.reset(prevCurrentBuffer.array(), resultFrameTupleAcc.getTupleStartOffset(resultTidx));
+
+            int cmp = invListCmp.compare(invListTuple, resultTuple);
+            if (cmp == 0) {
+                int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                        resultTuple.getFieldStart(resultTuple.getFieldCount() - 1)) + 1;
+                newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+                advanceCursor = true;
+                advancePrevResult = true;
+            } else {
+                if (cmp < 0) {
+                    advanceCursor = true;
+                    advancePrevResult = false;
+                } else {
+                    int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                            resultTuple.getFieldStart(resultTuple.getFieldCount() - 1));
+                    if (count + numQueryTokens - invListIx > occurrenceThreshold) {
+                        newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+                    }
+                    advanceCursor = false;
+                    advancePrevResult = true;
+                }
+            }
+
+            if (advancePrevResult) {
+                resultTidx++;
+                if (resultTidx >= resultFrameTupleAcc.getTupleCount()) {
+                    prevBufIdx++;
+                    if (prevBufIdx <= maxPrevBufIdx) {
+                        prevCurrentBuffer = prevResultBuffers.get(prevBufIdx);
+                        resultFrameTupleAcc.reset(prevCurrentBuffer);
+                        resultTidx = 0;
+                    }
+                }
+            }
+
+            if (advanceCursor) {
+                invListTidx++;
+                invListCursor.next();
+            }
+        }
+
+        // append remaining elements from previous result set
+        while (resultTidx < resultFrameTupleAcc.getTupleCount()) {
+
+            resultTuple.reset(prevCurrentBuffer.array(), resultFrameTupleAcc.getTupleStartOffset(resultTidx));
+
+            int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                    resultTuple.getFieldStart(resultTuple.getFieldCount() - 1));
+            if (count + numQueryTokens - invListIx > occurrenceThreshold) {
+                newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+            }
+
+            resultTidx++;
+            if (resultTidx >= resultFrameTupleAcc.getTupleCount()) {
+                prevBufIdx++;
+                if (prevBufIdx <= maxPrevBufIdx) {
+                    prevCurrentBuffer = prevResultBuffers.get(prevBufIdx);
+                    resultFrameTupleAcc.reset(prevCurrentBuffer);
+                    resultTidx = 0;
+                }
+            }
+        }
+
+        return newBufIdx;
+    }
+
+    protected int mergePrefixList(IInvertedListCursor invListCursor, List<ByteBuffer> prevResultBuffers,
+            int maxPrevBufIdx, List<ByteBuffer> newResultBuffers) throws IOException {
+        int newBufIdx = 0;
+        ByteBuffer newCurrentBuffer = newResultBuffers.get(0);
+
+        int prevBufIdx = 0;
+        ByteBuffer prevCurrentBuffer = prevResultBuffers.get(0);
+
+        boolean advanceCursor = true;
+        boolean advancePrevResult = false;
+        int resultTidx = 0;
+
+        MultiComparator invListCmp = invIndex.getInvListElementCmp();
+
+        resultFrameTupleAcc.reset(prevCurrentBuffer);
+        resultFrameTupleApp.reset(newCurrentBuffer, true);
+
+        int invListTidx = 0;
+        int invListNumTuples = invListCursor.getNumElements();
+
+        if (invListCursor.hasNext())
+            invListCursor.next();
+
+        while (invListTidx < invListNumTuples && resultTidx < resultFrameTupleAcc.getTupleCount()) {
+
+            ITupleReference invListTuple = invListCursor.getTuple();
+            resultTuple.reset(prevCurrentBuffer.array(), resultFrameTupleAcc.getTupleStartOffset(resultTidx));
+
+            int cmp = invListCmp.compare(invListTuple, resultTuple);
+            if (cmp == 0) {
+                int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                        resultTuple.getFieldStart(resultTuple.getFieldCount() - 1)) + 1;
+                newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+                advanceCursor = true;
+                advancePrevResult = true;
+            } else {
+                if (cmp < 0) {
+                    int count = 1;
+                    newBufIdx = appendTupleToNewResults(invListTuple, count, newBufIdx);
+                    advanceCursor = true;
+                    advancePrevResult = false;
+                } else {
+                    int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                            resultTuple.getFieldStart(resultTuple.getFieldCount() - 1));
+                    newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+                    advanceCursor = false;
+                    advancePrevResult = true;
+                }
+            }
+
+            if (advancePrevResult) {
+                resultTidx++;
+                if (resultTidx >= resultFrameTupleAcc.getTupleCount()) {
+                    prevBufIdx++;
+                    if (prevBufIdx <= maxPrevBufIdx) {
+                        prevCurrentBuffer = prevResultBuffers.get(prevBufIdx);
+                        resultFrameTupleAcc.reset(prevCurrentBuffer);
+                        resultTidx = 0;
+                    }
+                }
+            }
+
+            if (advanceCursor) {
+                invListTidx++;
+                invListCursor.next();
+            }
+        }
+
+        // append remaining new elements from inverted list
+        while (invListTidx < invListNumTuples) {
+            ITupleReference invListTuple = invListCursor.getTuple();
+            newBufIdx = appendTupleToNewResults(invListTuple, 1, newBufIdx);
+            invListTidx++;
+            invListCursor.next();
+        }
+
+        // append remaining elements from previous result set
+        while (resultTidx < resultFrameTupleAcc.getTupleCount()) {
+
+            resultTuple.reset(prevCurrentBuffer.array(), resultFrameTupleAcc.getTupleStartOffset(resultTidx));
+
+            int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                    resultTuple.getFieldStart(resultTuple.getFieldCount() - 1));
+            newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+
+            resultTidx++;
+            if (resultTidx >= resultFrameTupleAcc.getTupleCount()) {
+                prevBufIdx++;
+                if (prevBufIdx <= maxPrevBufIdx) {
+                    prevCurrentBuffer = prevResultBuffers.get(prevBufIdx);
+                    resultFrameTupleAcc.reset(prevCurrentBuffer);
+                    resultTidx = 0;
+                }
+            }
+        }
+
+        return newBufIdx;
+    }
+
+    protected int appendTupleToNewResults(ITupleReference tuple, int newCount, int newBufIdx) throws IOException {
+        ByteBuffer newCurrentBuffer = newResultBuffers.get(newBufIdx);
+
+        if (!resultFrameTupleApp.hasSpace()) {
+            newBufIdx++;
+            if (newBufIdx >= newResultBuffers.size()) {
+                newResultBuffers.add(ctx.allocateFrame());
+            }
+            newCurrentBuffer = newResultBuffers.get(newBufIdx);
+            resultFrameTupleApp.reset(newCurrentBuffer, true);
+        }
+
+        // append key
+        if (!resultFrameTupleApp.append(tuple.getFieldData(0), tuple.getFieldStart(0), invListKeyLength)) {
+            throw new IllegalStateException();
+        }
+
+        // append new count
+        if (!resultFrameTupleApp.append(newCount)) {
+            throw new IllegalStateException();
+        }
+
+        resultFrameTupleApp.incrementTupleCount(1);
+
+        currentNumResults++;
+
+        return newBufIdx;
+    }
+
+    public IFrameTupleAccessor createResultFrameTupleAccessor() {
+        return new FixedSizeFrameTupleAccessor(ctx.getFrameSize(), invListFieldsWithCount);
+    }
+
+    public ITupleReference createResultTupleReference() {
+        return new FixedSizeTupleReference(invListFieldsWithCount);
+    }
+
+    @Override
+    public List<ByteBuffer> getResultBuffers() {
+        return newResultBuffers;
+    }
+
+    @Override
+    public int getNumValidResultBuffers() {
+        return maxResultBufIdx + 1;
+    }
+
+    public int getOccurrenceThreshold() {
+        return occurrenceThreshold;
+    }
+
+    public void printNewResults(int maxResultBufIdx) {
+        StringBuffer strBuffer = new StringBuffer();
+        for (int i = 0; i <= maxResultBufIdx; i++) {
+            ByteBuffer testBuf = newResultBuffers.get(i);
+            resultFrameTupleAcc.reset(testBuf);
+            for (int j = 0; j < resultFrameTupleAcc.getTupleCount(); j++) {
+                strBuffer.append(IntegerSerializerDeserializer.getInt(resultFrameTupleAcc.getBuffer().array(),
+                        resultFrameTupleAcc.getFieldStartOffset(j, 0)) + ",");
+                strBuffer.append(IntegerSerializerDeserializer.getInt(resultFrameTupleAcc.getBuffer().array(),
+                        resultFrameTupleAcc.getFieldStartOffset(j, 1)) + " ");
+            }
+        }
+        System.out.println(strBuffer.toString());
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixProbeOnly.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixProbeOnly.java
new file mode 100644
index 0000000..30d67f0
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixProbeOnly.java
@@ -0,0 +1,94 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.List;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizer;
+
+public class TOccurrenceSearcherSuffixProbeOnly extends TOccurrenceSearcher {
+
+    public TOccurrenceSearcherSuffixProbeOnly(IHyracksStageletContext ctx, InvertedIndex invIndex,
+            IBinaryTokenizer queryTokenizer) {
+        super(ctx, invIndex, queryTokenizer);
+    }
+
+    protected int mergeSuffixLists(int numPrefixTokens, int numQueryTokens, int maxPrevBufIdx) throws IOException {
+        for (int i = numPrefixTokens; i < numQueryTokens; i++) {
+            swap = prevResultBuffers;
+            prevResultBuffers = newResultBuffers;
+            newResultBuffers = swap;
+            currentNumResults = 0;
+
+            invListCursors.get(i).pinPagesSync();
+            maxPrevBufIdx = mergeSuffixListProbe(invListCursors.get(i), prevResultBuffers, maxPrevBufIdx,
+                    newResultBuffers, i, numQueryTokens);
+            invListCursors.get(i).unpinPages();
+        }
+        return maxPrevBufIdx;
+    }
+
+    protected int mergeSuffixListProbe(IInvertedListCursor invListCursor, List<ByteBuffer> prevResultBuffers,
+            int maxPrevBufIdx, List<ByteBuffer> newResultBuffers, int invListIx, int numQueryTokens) throws IOException {
+
+        int newBufIdx = 0;
+        ByteBuffer newCurrentBuffer = newResultBuffers.get(0);
+
+        int prevBufIdx = 0;
+        ByteBuffer prevCurrentBuffer = prevResultBuffers.get(0);
+
+        int resultTidx = 0;
+
+        MultiComparator invListCmp = invIndex.getInvListElementCmp();
+
+        resultFrameTupleAcc.reset(prevCurrentBuffer);
+        resultFrameTupleApp.reset(newCurrentBuffer, true);
+
+        while (resultTidx < resultFrameTupleAcc.getTupleCount()) {
+
+            resultTuple.reset(prevCurrentBuffer.array(), resultFrameTupleAcc.getTupleStartOffset(resultTidx));
+            int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                    resultTuple.getFieldStart(resultTuple.getFieldCount() - 1));
+
+            if (invListCursor.containsKey(resultTuple, invListCmp)) {
+                count++;
+                newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+            } else {
+                if (count + numQueryTokens - invListIx > occurrenceThreshold) {
+                    newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+                }
+            }
+
+            resultTidx++;
+            if (resultTidx >= resultFrameTupleAcc.getTupleCount()) {
+                prevBufIdx++;
+                if (prevBufIdx <= maxPrevBufIdx) {
+                    prevCurrentBuffer = prevResultBuffers.get(prevBufIdx);
+                    resultFrameTupleAcc.reset(prevCurrentBuffer);
+                    resultTidx = 0;
+                }
+            }
+        }
+
+        return newBufIdx;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixScanOnly.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixScanOnly.java
new file mode 100644
index 0000000..f8bc1ab
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/impls/TOccurrenceSearcherSuffixScanOnly.java
@@ -0,0 +1,133 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.impls;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.List;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizer;
+
+public class TOccurrenceSearcherSuffixScanOnly extends TOccurrenceSearcher {
+
+    public TOccurrenceSearcherSuffixScanOnly(IHyracksStageletContext ctx, InvertedIndex invIndex,
+            IBinaryTokenizer queryTokenizer) {
+        super(ctx, invIndex, queryTokenizer);
+    }
+
+    protected int mergeSuffixLists(int numPrefixTokens, int numQueryTokens, int maxPrevBufIdx) throws IOException {
+        for (int i = numPrefixTokens; i < numQueryTokens; i++) {
+            swap = prevResultBuffers;
+            prevResultBuffers = newResultBuffers;
+            newResultBuffers = swap;
+            currentNumResults = 0;
+
+            invListCursors.get(i).pinPagesSync();
+            maxPrevBufIdx = mergeSuffixListScan(invListCursors.get(i), prevResultBuffers, maxPrevBufIdx,
+                    newResultBuffers, i, numQueryTokens);
+            invListCursors.get(i).unpinPages();
+        }
+        return maxPrevBufIdx;
+    }
+
+    protected int mergeSuffixListScan(IInvertedListCursor invListCursor, List<ByteBuffer> prevResultBuffers,
+            int maxPrevBufIdx, List<ByteBuffer> newResultBuffers, int invListIx, int numQueryTokens) throws IOException {
+
+        int newBufIdx = 0;
+        ByteBuffer newCurrentBuffer = newResultBuffers.get(0);
+
+        int prevBufIdx = 0;
+        ByteBuffer prevCurrentBuffer = prevResultBuffers.get(0);
+
+        boolean advanceCursor = true;
+        boolean advancePrevResult = false;
+        int resultTidx = 0;
+
+        MultiComparator invListCmp = invIndex.getInvListElementCmp();
+
+        resultFrameTupleAcc.reset(prevCurrentBuffer);
+        resultFrameTupleApp.reset(newCurrentBuffer, true);
+
+        while (invListCursor.hasNext() && resultTidx < resultFrameTupleAcc.getTupleCount()) {
+
+            if (advanceCursor)
+                invListCursor.next();
+
+            ITupleReference invListTuple = invListCursor.getTuple();
+
+            resultTuple.reset(prevCurrentBuffer.array(), resultFrameTupleAcc.getTupleStartOffset(resultTidx));
+
+            int cmp = invListCmp.compare(invListTuple, resultTuple);
+            if (cmp == 0) {
+                int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                        resultTuple.getFieldStart(resultTuple.getFieldCount() - 1)) + 1;
+                newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+                advanceCursor = true;
+                advancePrevResult = true;
+            } else {
+                if (cmp < 0) {
+                    advanceCursor = true;
+                    advancePrevResult = false;
+                } else {
+                    int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                            resultTuple.getFieldStart(resultTuple.getFieldCount() - 1));
+                    if (count + numQueryTokens - invListIx > occurrenceThreshold) {
+                        newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+                    }
+                    advanceCursor = false;
+                    advancePrevResult = true;
+                }
+            }
+
+            if (advancePrevResult) {
+                resultTidx++;
+                if (resultTidx >= resultFrameTupleAcc.getTupleCount()) {
+                    prevBufIdx++;
+                    if (prevBufIdx <= maxPrevBufIdx) {
+                        prevCurrentBuffer = prevResultBuffers.get(prevBufIdx);
+                        resultFrameTupleAcc.reset(prevCurrentBuffer);
+                        resultTidx = 0;
+                    }
+                }
+            }
+        }
+
+        // append remaining elements from previous result set
+        while (resultTidx < resultFrameTupleAcc.getTupleCount()) {
+
+            int count = IntegerSerializerDeserializer.getInt(resultTuple.getFieldData(0),
+                    resultTuple.getFieldStart(resultTuple.getFieldCount() - 1));
+            newBufIdx = appendTupleToNewResults(resultTuple, count, newBufIdx);
+
+            resultTidx++;
+            if (resultTidx >= resultFrameTupleAcc.getTupleCount()) {
+                prevBufIdx++;
+                if (prevBufIdx <= maxPrevBufIdx) {
+                    prevCurrentBuffer = prevResultBuffers.get(prevBufIdx);
+                    resultFrameTupleAcc.reset(prevCurrentBuffer);
+                    resultTidx = 0;
+                }
+            }
+        }
+
+        return newBufIdx;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchmodifiers/ConjunctiveSearchModifier.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchmodifiers/ConjunctiveSearchModifier.java
new file mode 100644
index 0000000..55945be
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchmodifiers/ConjunctiveSearchModifier.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.searchmodifiers;
+
+import java.util.Collections;
+import java.util.List;
+
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexSearchModifier;
+
+public class ConjunctiveSearchModifier implements IInvertedIndexSearchModifier {
+
+    @Override
+    public int getOccurrenceThreshold(List<IInvertedListCursor> invListCursors) {
+        return invListCursors.size();
+    }
+
+    @Override
+    public int getPrefixLists(List<IInvertedListCursor> invListCursors) {
+        Collections.sort(invListCursors);
+        return 1;
+    }
+
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchmodifiers/EditDistanceSearchModifier.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchmodifiers/EditDistanceSearchModifier.java
new file mode 100644
index 0000000..ac109b6
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchmodifiers/EditDistanceSearchModifier.java
@@ -0,0 +1,60 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.searchmodifiers;
+
+import java.util.Collections;
+import java.util.List;
+
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexSearchModifier;
+
+public class EditDistanceSearchModifier implements IInvertedIndexSearchModifier {
+
+    private int gramLength;
+    private int edThresh;
+
+    public EditDistanceSearchModifier(int gramLength, int edThresh) {
+        this.gramLength = gramLength;
+        this.edThresh = edThresh;
+    }
+
+    @Override
+    public int getOccurrenceThreshold(List<IInvertedListCursor> invListCursors) {
+        return invListCursors.size() - edThresh * gramLength;
+    }
+
+    @Override
+    public int getPrefixLists(List<IInvertedListCursor> invListCursors) {
+        Collections.sort(invListCursors);
+        return invListCursors.size() - getOccurrenceThreshold(invListCursors) + 1;
+    }
+
+    public int getGramLength() {
+        return gramLength;
+    }
+
+    public void setGramLength(int gramLength) {
+        this.gramLength = gramLength;
+    }
+
+    public int getEdThresh() {
+        return edThresh;
+    }
+
+    public void setEdThresh(int edThresh) {
+        this.edThresh = edThresh;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchmodifiers/JaccardSearchModifier.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchmodifiers/JaccardSearchModifier.java
new file mode 100644
index 0000000..f42841c
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchmodifiers/JaccardSearchModifier.java
@@ -0,0 +1,53 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.searchmodifiers;
+
+import java.util.Collections;
+import java.util.List;
+
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexSearchModifier;
+
+public class JaccardSearchModifier implements IInvertedIndexSearchModifier {
+
+    private float jaccThresh;
+
+    public JaccardSearchModifier(float jaccThresh) {
+        this.jaccThresh = jaccThresh;
+    }
+
+    @Override
+    public int getOccurrenceThreshold(List<IInvertedListCursor> invListCursors) {
+        return (int) Math.floor((float) invListCursors.size() * jaccThresh);
+    }
+
+    @Override
+    public int getPrefixLists(List<IInvertedListCursor> invListCursors) {
+        Collections.sort(invListCursors);
+        if (invListCursors.size() == 0) {
+            return 0;
+        }
+        return invListCursors.size() - getOccurrenceThreshold(invListCursors) + 1;
+    }
+
+    public float getJaccThresh() {
+        return jaccThresh;
+    }
+
+    public void setJaccThresh(float jaccThresh) {
+        this.jaccThresh = jaccThresh;
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/AbstractUTF8StringBinaryTokenizer.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/AbstractUTF8StringBinaryTokenizer.java
new file mode 100644
index 0000000..bbb32d6
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/AbstractUTF8StringBinaryTokenizer.java
@@ -0,0 +1,78 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import edu.uci.ics.hyracks.dataflow.common.data.util.StringUtils;
+
+public abstract class AbstractUTF8StringBinaryTokenizer implements
+		IBinaryTokenizer {
+
+	protected byte[] data;
+	protected int start;
+	protected int length;
+	protected int tokenLength;
+	protected int index;
+	protected int utf8Length;
+
+	protected final IntArray tokensStart;
+	protected final IntArray tokensLength;
+	protected final IToken token;
+
+	protected final boolean ignoreTokenCount;
+	protected final boolean sourceHasTypeTag;
+
+	public AbstractUTF8StringBinaryTokenizer(boolean ignoreTokenCount,
+			boolean sourceHasTypeTag, ITokenFactory tokenFactory) {
+		this.ignoreTokenCount = ignoreTokenCount;
+		this.sourceHasTypeTag = sourceHasTypeTag;
+		if (!ignoreTokenCount) {
+			tokensStart = new IntArray();
+			tokensLength = new IntArray();
+		} else {
+			tokensStart = null;
+			tokensLength = null;
+		}
+		token = tokenFactory.createToken();
+	}
+
+	@Override
+	public IToken getToken() {
+		return token;
+	}
+
+	@Override
+	public void reset(byte[] data, int start, int length) {
+		this.start = start;
+		index = this.start;
+		if (sourceHasTypeTag) {
+			index++; // skip type tag
+		}
+		utf8Length = StringUtils.getUTFLen(data, index);
+		index += 2; // skip utf8 length indicator
+		this.data = data;
+		this.length = length + start;
+
+		tokenLength = 0;
+		if (!ignoreTokenCount) {
+			tokensStart.reset();
+			tokensLength.reset();
+		}
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/AbstractUTF8Token.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/AbstractUTF8Token.java
new file mode 100644
index 0000000..92d6ac2
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/AbstractUTF8Token.java
@@ -0,0 +1,106 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import java.io.DataOutput;
+import java.io.IOException;
+
+import edu.uci.ics.hyracks.dataflow.common.data.util.StringUtils;
+
+public abstract class AbstractUTF8Token implements IToken {
+	public static final int GOLDEN_RATIO_32 = 0x09e3779b9;
+
+	protected int length;
+	protected int tokenLength;
+	protected int start;
+	protected int tokenCount;
+	protected byte[] data;
+	protected final byte tokenTypeTag;
+	protected final byte countTypeTag;
+
+	public AbstractUTF8Token() {
+		tokenTypeTag = -1;
+		countTypeTag = -1;
+	}
+
+	public AbstractUTF8Token(byte tokenTypeTag, byte countTypeTag) {
+		this.tokenTypeTag = tokenTypeTag;
+		this.countTypeTag = countTypeTag;
+	}
+
+	@Override
+	public byte[] getData() {
+		return data;
+	}
+
+	@Override
+	public int getLength() {
+		return length;
+	}
+
+	public int getLowerCaseUTF8Len(int size) {
+		int lowerCaseUTF8Len = 0;
+		int pos = start;
+		for (int i = 0; i < size; i++) {
+			char c = StringUtils.toLowerCase(StringUtils.charAt(data, pos));
+			lowerCaseUTF8Len += StringUtils.getModifiedUTF8Len(c);
+			pos += StringUtils.charSize(data, pos);
+		}
+		return lowerCaseUTF8Len;
+	}
+
+	@Override
+	public int getStart() {
+		return start;
+	}
+
+	@Override
+	public int getTokenLength() {
+		return tokenLength;
+	}
+
+	public void handleCountTypeTag(DataOutput dos) throws IOException {
+		if (countTypeTag > 0) {
+			dos.write(countTypeTag);
+		}
+	}
+
+	public void handleTokenTypeTag(DataOutput dos) throws IOException {
+		if (tokenTypeTag > 0) {
+			dos.write(tokenTypeTag);
+		}
+	}
+
+	@Override
+	public void reset(byte[] data, int start, int length, int tokenLength,
+			int tokenCount) {
+		this.data = data;
+		this.start = start;
+		this.length = length;
+		this.tokenLength = tokenLength;
+		this.tokenCount = tokenCount;
+	}
+
+	@Override
+	public void serializeTokenCount(DataOutput dos) throws IOException {
+		handleCountTypeTag(dos);
+		dos.writeInt(tokenCount);
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/AbstractUTF8TokenFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/AbstractUTF8TokenFactory.java
new file mode 100644
index 0000000..3b0b82d
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/AbstractUTF8TokenFactory.java
@@ -0,0 +1,36 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+public abstract class AbstractUTF8TokenFactory implements ITokenFactory {
+	private static final long serialVersionUID = 1L;
+	protected final byte tokenTypeTag;
+	protected final byte countTypeTag;
+
+	public AbstractUTF8TokenFactory() {
+		tokenTypeTag = -1;
+		countTypeTag = -1;
+	}
+
+	public AbstractUTF8TokenFactory(byte tokenTypeTag, byte countTypeTag) {
+		this.tokenTypeTag = tokenTypeTag;
+		this.countTypeTag = countTypeTag;
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/DelimitedUTF8StringBinaryTokenizer.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/DelimitedUTF8StringBinaryTokenizer.java
index 425436b..de9ad2c 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/DelimitedUTF8StringBinaryTokenizer.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/DelimitedUTF8StringBinaryTokenizer.java
@@ -1,116 +1,87 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
+ * You may obtain a copy of the License at
+ *
  *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
  * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
  */
 
 package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
 
-import java.io.DataOutput;
-import java.io.IOException;
-
-import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
 import edu.uci.ics.hyracks.dataflow.common.data.util.StringUtils;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizer;
 
-public class DelimitedUTF8StringBinaryTokenizer implements IBinaryTokenizer {
+public class DelimitedUTF8StringBinaryTokenizer extends
+		AbstractUTF8StringBinaryTokenizer {
 
-    private static final RecordDescriptor tokenSchema = new RecordDescriptor(
-            new ISerializerDeserializer[] { UTF8StringSerializerDeserializer.INSTANCE });
+	public DelimitedUTF8StringBinaryTokenizer(boolean ignoreTokenCount,
+			boolean sourceHasTypeTag, ITokenFactory tokenFactory) {
+		super(ignoreTokenCount, sourceHasTypeTag, tokenFactory);
+	}
 
-    private final char delimiter;
-    private final byte typeTag;
-    private byte[] data;
-    private int start;
-    private int length;
+	@Override
+	public boolean hasNext() {
+		// skip delimiters
+		while (index < length && isSeparator(StringUtils.charAt(data, index))) {
+			index += StringUtils.charSize(data, index);
+		}
+		return index < length;
+	}
 
-    private int tokenLength;
-    private int tokenStart;
-    private int pos;
+	private boolean isSeparator(char c) {
+		return !(Character.isLetterOrDigit(c)
+				|| Character.getType(c) == Character.OTHER_LETTER || Character
+				.getType(c) == Character.OTHER_NUMBER);
+	}
 
-    public DelimitedUTF8StringBinaryTokenizer(char delimiter, byte typeTag) {
-        this.delimiter = delimiter;
-        this.typeTag = typeTag;
-    }
+	@Override
+	public void next() {
+		tokenLength = 0;
+		int currentTokenStart = index;
+		while (index < length && !isSeparator(StringUtils.charAt(data, index))) {
+			index += StringUtils.charSize(data, index);
+			tokenLength++;
+		}
+		int tokenCount = 1;
+		if (tokenLength > 0 && !ignoreTokenCount) {
+			// search if we got the same token before
+			for (int i = 0; i < tokensStart.length(); ++i) {
+				if (tokenLength == tokensLength.get(i)) {
+					int tokenStart = tokensStart.get(i);
+					tokenCount++; // assume we found it
+					int offset = 0;
+					int currLength = 0;
+					while (currLength < tokenLength) {
+						// case insensitive comparison
+						if (StringUtils.toLowerCase(StringUtils.charAt(data,
+								currentTokenStart + offset)) != StringUtils
+								.toLowerCase(StringUtils.charAt(data,
+										tokenStart + offset))) {
+							tokenCount--;
+							break;
+						}
+						offset += StringUtils.charSize(data, currentTokenStart
+								+ offset);
+						currLength++;
+					}
+				}
+			}
+			// add the new token to the list of seen tokens
+			tokensStart.add(currentTokenStart);
+			tokensLength.add(tokenLength);
+		}
 
-    public DelimitedUTF8StringBinaryTokenizer(char delimiter) {
-        this.delimiter = delimiter;
-        this.typeTag = -1;
-    }
-
-    @Override
-    public int getTokenLength() {
-        return tokenLength;
-    }
-
-    @Override
-    public int getTokenStartOff() {
-        return tokenStart;
-    }
-
-    @Override
-    public boolean hasNext() {
-        if (pos >= start + length)
-            return false;
-        else
-            return true;
-    }
-
-    @Override
-    public void next() {
-        tokenLength = 0;
-        tokenStart = pos;
-        while (pos < start + length) {
-            int len = StringUtils.charSize(data, pos);
-            char ch = StringUtils.charAt(data, pos);
-            pos += len;
-            if (ch == delimiter) {
-                break;
-            }
-            tokenLength += len;
-        }
-    }
-
-    @Override
-    public void reset(byte[] data, int start, int length) {
-        this.data = data;
-        this.start = start;
-        this.pos = start;
-        this.length = length;
-        this.tokenLength = 0;
-        this.tokenStart = 0;
-        pos += 2; // UTF-8 specific
-    }
-
-    @Override
-    public void writeToken(DataOutput dos) throws IOException {
-        if (typeTag > 0)
-            dos.write(typeTag);
-
-        // WARNING: 2-byte length indicator is specific to UTF-8
-        dos.writeShort((short) tokenLength);
-        dos.write(data, tokenStart, tokenLength);
-    }
-
-    @Override
-    public RecordDescriptor getTokenSchema() {
-        return tokenSchema;
-    }
-
-    // cannot be implemented for this tokenizer
-    @Override
-    public int getNumTokens() {
-        return -1;
-    }
+		// set token
+		token.reset(data, currentTokenStart, index, tokenLength, tokenCount);
+	}
 }
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/DelimitedUTF8StringBinaryTokenizerFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/DelimitedUTF8StringBinaryTokenizerFactory.java
index 2e85db5..4a350b3 100644
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/DelimitedUTF8StringBinaryTokenizerFactory.java
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/DelimitedUTF8StringBinaryTokenizerFactory.java
@@ -1,41 +1,42 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
+ * You may obtain a copy of the License at
+ *
  *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
  * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
  */
 
 package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
 
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizer;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizerFactory;
+public class DelimitedUTF8StringBinaryTokenizerFactory implements
+		IBinaryTokenizerFactory {
 
-public class DelimitedUTF8StringBinaryTokenizerFactory implements IBinaryTokenizerFactory {
+	private static final long serialVersionUID = 1L;
+	private final boolean ignoreTokenCount;
+	private final boolean sourceHasTypeTag;
+	private final ITokenFactory tokenFactory;
 
-    private static final long serialVersionUID = 1L;
-    private final char delimiter;
-    private final byte typeTag;
+	public DelimitedUTF8StringBinaryTokenizerFactory(boolean ignoreTokenCount,
+			boolean sourceHasTypeTag, ITokenFactory tokenFactory) {
+		this.ignoreTokenCount = ignoreTokenCount;
+		this.sourceHasTypeTag = sourceHasTypeTag;
+		this.tokenFactory = tokenFactory;
+	}
 
-    public DelimitedUTF8StringBinaryTokenizerFactory(char delimiter, byte typeTag) {
-        this.delimiter = delimiter;
-        this.typeTag = typeTag;
-    }
-
-    public DelimitedUTF8StringBinaryTokenizerFactory(char delimiter) {
-        this.delimiter = delimiter;
-        this.typeTag = -1;
-    }
-
-    @Override
-    public IBinaryTokenizer createBinaryTokenizer() {
-        return new DelimitedUTF8StringBinaryTokenizer(delimiter, typeTag);
-    }
+	@Override
+	public IBinaryTokenizer createTokenizer() {
+		return new DelimitedUTF8StringBinaryTokenizer(ignoreTokenCount,
+				sourceHasTypeTag, tokenFactory);
+	}
 }
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedQGramUTF8StringBinaryTokenizer.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedQGramUTF8StringBinaryTokenizer.java
deleted file mode 100644
index 2cc0b6c..0000000
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedQGramUTF8StringBinaryTokenizer.java
+++ /dev/null
@@ -1,150 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
-
-import java.io.DataOutput;
-import java.io.IOException;
-
-import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
-import edu.uci.ics.hyracks.dataflow.common.data.util.StringUtils;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizer;
-
-public class HashedQGramUTF8StringBinaryTokenizer implements IBinaryTokenizer {
-
-    private static final RecordDescriptor tokenSchema = new RecordDescriptor(
-            new ISerializerDeserializer[] { IntegerSerializerDeserializer.INSTANCE });
-
-    private final boolean prePost;
-    private final int q;
-    private byte[] data;
-    private int start;
-    private int length;
-    private int gramNum;
-    private int utflen;
-
-    private final char PRECHAR = '#';
-    private final char POSTCHAR = '$';
-
-    private int charPos;
-    private int pos;
-    private int hashedGram;
-
-    HashedQGramUTF8StringBinaryTokenizer(int q, boolean prePost) {
-        this.prePost = prePost;
-        this.q = q;
-    }
-
-    @Override
-    public int getTokenLength() {
-        // the produced token (hashed q-gram) is derived from data
-        // but not contained in it
-        // therefore this call does not make sense
-        return -1;
-    }
-
-    @Override
-    public int getTokenStartOff() {
-        // the produced token (hashed q-gram) is derived from data
-        // but not contained in it
-        // therefore this call does not make sense
-        return -1;
-    }
-
-    @Override
-    public boolean hasNext() {
-        if ((prePost && pos >= start + length) || (!prePost && pos >= start + length - q))
-            return false;
-        else
-            return true;
-    }
-
-    @Override
-    public void next() {
-        hashedGram = 0;
-        if (prePost) {
-            if (gramNum < q) {
-                for (int i = 0; i < q - gramNum; i++) {
-                    hashedGram = 31 * hashedGram + PRECHAR;
-                }
-
-                int tmpPos = pos;
-                for (int i = 0; i < gramNum; i++) {
-                    hashedGram = 31 * hashedGram + StringUtils.charAt(data, tmpPos);
-                    tmpPos += StringUtils.charSize(data, tmpPos);
-                }
-            } else {
-                int stopStr = Math.min(charPos + q, utflen);
-                int tmpPos = pos;
-                for (int i = charPos; i < stopStr; i++) {
-                    hashedGram = 31 * hashedGram + StringUtils.charAt(data, tmpPos);
-                    tmpPos += StringUtils.charSize(data, tmpPos);
-                }
-
-                int stopPost = (charPos + q) - (utflen);
-                for (int i = 0; i < stopPost; i++) {
-                    hashedGram = 31 * hashedGram + POSTCHAR;
-                }
-                pos += StringUtils.charSize(data, pos);
-                charPos++;
-            }
-            gramNum++;
-        } else {
-            int tmpPos = pos;
-            for (int i = charPos; i < charPos + q; i++) {
-                hashedGram = 31 * hashedGram + StringUtils.charAt(data, tmpPos);
-                tmpPos += StringUtils.charSize(data, tmpPos);
-            }
-            pos += StringUtils.charSize(data, pos);
-            charPos++;
-        }
-    }
-
-    @Override
-    public void reset(byte[] data, int start, int length) {
-        this.data = data;
-        this.start = start;
-        this.length = length;
-        this.utflen = StringUtils.getUTFLen(data, start);
-        this.pos = start + 2; // UTF-8 specific
-        this.gramNum = 1;
-        this.charPos = 0;
-    }
-
-    @Override
-    public void writeToken(DataOutput dos) throws IOException {
-        dos.writeInt(hashedGram);
-    }
-
-    public char getPreChar() {
-        return PRECHAR;
-    }
-
-    public char getPostChar() {
-        return POSTCHAR;
-    }
-
-    @Override
-    public RecordDescriptor getTokenSchema() {
-        return tokenSchema;
-    }
-
-    @Override
-    public int getNumTokens() {
-        return 0;
-    }
-}
\ No newline at end of file
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedQGramUTF8StringBinaryTokenizerFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedQGramUTF8StringBinaryTokenizerFactory.java
deleted file mode 100644
index a11fe8a..0000000
--- a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedQGramUTF8StringBinaryTokenizerFactory.java
+++ /dev/null
@@ -1,36 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
-
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizer;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizerFactory;
-
-public class HashedQGramUTF8StringBinaryTokenizerFactory implements IBinaryTokenizerFactory {
-
-    private static final long serialVersionUID = 1L;
-    private final int q;
-    private final boolean prePost;
-
-    public HashedQGramUTF8StringBinaryTokenizerFactory(int q, boolean prePost) {
-        this.q = q;
-        this.prePost = prePost;
-    }
-
-    @Override
-    public IBinaryTokenizer createBinaryTokenizer() {
-        return new HashedQGramUTF8StringBinaryTokenizer(q, prePost);
-    }
-}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8NGramToken.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8NGramToken.java
new file mode 100644
index 0000000..25d1a2c
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8NGramToken.java
@@ -0,0 +1,64 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import java.io.DataOutput;
+import java.io.IOException;
+
+import edu.uci.ics.hyracks.dataflow.common.data.util.StringUtils;
+
+public class HashedUTF8NGramToken extends UTF8NGramToken {
+	public HashedUTF8NGramToken(byte tokenTypeTag, byte countTypeTag) {
+		super(tokenTypeTag, countTypeTag);
+	}
+
+	@Override
+	public void serializeToken(DataOutput dos) throws IOException {
+		handleTokenTypeTag(dos);
+
+		int hash = GOLDEN_RATIO_32;
+
+		// pre chars
+		for (int i = 0; i < numPreChars; i++) {
+			hash ^= PRECHAR;
+			hash *= GOLDEN_RATIO_32;
+		}
+
+		// regular chars
+		int numRegGrams = tokenLength - numPreChars - numPostChars;
+		int pos = start;
+		for (int i = 0; i < numRegGrams; i++) {
+			hash ^= StringUtils.toLowerCase(StringUtils.charAt(data, pos));
+			hash *= GOLDEN_RATIO_32;
+			pos += StringUtils.charSize(data, pos);
+		}
+
+		// post chars
+		for (int i = 0; i < numPostChars; i++) {
+			hash ^= POSTCHAR;
+			hash *= GOLDEN_RATIO_32;
+		}
+
+		// token count
+		hash += tokenCount;
+
+		dos.writeInt(hash);
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8NGramTokenFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8NGramTokenFactory.java
new file mode 100644
index 0000000..4a87793
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8NGramTokenFactory.java
@@ -0,0 +1,38 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+public class HashedUTF8NGramTokenFactory extends AbstractUTF8TokenFactory {
+
+	private static final long serialVersionUID = 1L;
+
+	public HashedUTF8NGramTokenFactory() {
+		super();
+	}
+
+	public HashedUTF8NGramTokenFactory(byte tokenTypeTag, byte countTypeTag) {
+		super(tokenTypeTag, countTypeTag);
+	}
+
+	@Override
+	public IToken createToken() {
+		return new HashedUTF8NGramToken(tokenTypeTag, countTypeTag);
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8WordToken.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8WordToken.java
new file mode 100644
index 0000000..55237ce
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8WordToken.java
@@ -0,0 +1,88 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import java.io.DataOutput;
+import java.io.IOException;
+
+import edu.uci.ics.hyracks.dataflow.common.data.util.StringUtils;
+
+public class HashedUTF8WordToken extends UTF8WordToken {
+
+	private int hash = 0;
+
+	public HashedUTF8WordToken(byte tokenTypeTag, byte countTypeTag) {
+		super(tokenTypeTag, countTypeTag);
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		if (o == null) {
+			return false;
+		}
+		if (!(o instanceof IToken)) {
+			return false;
+		}
+		IToken t = (IToken) o;
+		if (t.getTokenLength() != tokenLength) {
+			return false;
+		}
+		int offset = 0;
+		for (int i = 0; i < tokenLength; i++) {
+			if (StringUtils.charAt(t.getData(), t.getStart() + offset) != StringUtils
+					.charAt(data, start + offset)) {
+				return false;
+			}
+			offset += StringUtils.charSize(data, start + offset);
+		}
+		return true;
+	}
+
+	@Override
+	public int hashCode() {
+		return hash;
+	}
+
+	@Override
+	public void reset(byte[] data, int start, int length, int tokenLength,
+			int tokenCount) {
+		super.reset(data, start, length, tokenLength, tokenCount);
+
+		// pre-compute hash value using JAQL-like string hashing
+		int pos = start;
+		hash = GOLDEN_RATIO_32;
+		for (int i = 0; i < tokenLength; i++) {
+			hash ^= StringUtils.toLowerCase(StringUtils.charAt(data, pos));
+			hash *= GOLDEN_RATIO_32;
+			pos += StringUtils.charSize(data, pos);
+		}
+		hash += tokenCount;
+	}
+
+	@Override
+	public void serializeToken(DataOutput dos) throws IOException {
+		if (tokenTypeTag > 0) {
+			dos.write(tokenTypeTag);
+		}
+
+		// serialize hash value
+		dos.writeInt(hash);
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8WordTokenFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8WordTokenFactory.java
new file mode 100644
index 0000000..318f041
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/HashedUTF8WordTokenFactory.java
@@ -0,0 +1,38 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+public class HashedUTF8WordTokenFactory extends AbstractUTF8TokenFactory {
+
+	private static final long serialVersionUID = 1L;
+
+	public HashedUTF8WordTokenFactory() {
+		super();
+	}
+
+	public HashedUTF8WordTokenFactory(byte tokenTypeTag, byte countTypeTag) {
+		super(tokenTypeTag, countTypeTag);
+	}
+
+	@Override
+	public IToken createToken() {
+		return new HashedUTF8WordToken(tokenTypeTag, countTypeTag);
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IBinaryTokenizer.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IBinaryTokenizer.java
new file mode 100644
index 0000000..05c6d0b
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IBinaryTokenizer.java
@@ -0,0 +1,30 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+public interface IBinaryTokenizer {
+	public IToken getToken();
+
+	public boolean hasNext();
+
+	public void next();
+
+	public void reset(byte[] data, int start, int length);
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IBinaryTokenizerFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IBinaryTokenizerFactory.java
new file mode 100644
index 0000000..bfe78ee
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IBinaryTokenizerFactory.java
@@ -0,0 +1,26 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import java.io.Serializable;
+
+public interface IBinaryTokenizerFactory extends Serializable {
+	public IBinaryTokenizer createTokenizer();
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/INGramToken.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/INGramToken.java
new file mode 100644
index 0000000..befc6d2
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/INGramToken.java
@@ -0,0 +1,28 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+public interface INGramToken {
+	public int getNumPostChars();
+
+	public int getNumPreChars();
+
+	public void setNumPrePostChars(int numPreChars, int numPostChars);
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IToken.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IToken.java
new file mode 100644
index 0000000..c1840d7
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IToken.java
@@ -0,0 +1,40 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import java.io.DataOutput;
+import java.io.IOException;
+
+public interface IToken {
+	public byte[] getData();
+
+	public int getLength();
+
+	public int getStart();
+
+	public int getTokenLength();
+
+	public void reset(byte[] data, int start, int length, int tokenLength,
+			int tokenCount);
+
+	public void serializeToken(DataOutput dos) throws IOException;
+
+	public void serializeTokenCount(DataOutput dos) throws IOException;
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/ITokenFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/ITokenFactory.java
new file mode 100644
index 0000000..8b5d71d
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/ITokenFactory.java
@@ -0,0 +1,26 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import java.io.Serializable;
+
+public interface ITokenFactory extends Serializable {
+    public IToken createToken();
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IntArray.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IntArray.java
new file mode 100644
index 0000000..2eb9ff4
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/IntArray.java
@@ -0,0 +1,80 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Rares Vernica <rares (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import java.util.Arrays;
+
+public class IntArray {
+    private static final int SIZE = 128;
+
+    private int[] data;
+    private int length;
+
+    public IntArray() {
+        data = new int[SIZE];
+        length = 0;
+    }
+
+    public void add(int d) {
+        if (length == data.length) {
+            data = Arrays.copyOf(data, data.length << 1);
+        }
+        data[length++] = d;
+    }
+
+    public int[] get() {
+        return data;
+    }
+
+    public int get(int i) {
+        return data[i];
+    }
+
+    public int length() {
+        return length;
+    }
+
+    public void reset() {
+        length = 0;
+    }
+
+    public void sort() {
+        sort(0, length);
+    }
+
+    public void sort(int start, int end) {
+        Arrays.sort(data, start, end);
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder out = new StringBuilder();
+        out.append('[');
+        for (int i = 0; i < length; ++i) {
+            out.append(data[i]);
+            if (i < length - 1) {
+                out.append(',');
+                out.append(' ');
+            }
+        }
+        out.append(']');
+        return out.toString();
+    }
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/NGramUTF8StringBinaryTokenizer.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/NGramUTF8StringBinaryTokenizer.java
new file mode 100644
index 0000000..2a13f83
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/NGramUTF8StringBinaryTokenizer.java
@@ -0,0 +1,123 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import edu.uci.ics.hyracks.dataflow.common.data.util.StringUtils;
+
+public class NGramUTF8StringBinaryTokenizer extends
+		AbstractUTF8StringBinaryTokenizer {
+
+	private int gramLength;
+	private boolean usePrePost;
+
+	private int gramNum;
+	private int totalGrams;
+
+	private final INGramToken concreteToken;
+
+	public NGramUTF8StringBinaryTokenizer(int gramLength, boolean usePrePost,
+			boolean ignoreTokenCount, boolean sourceHasTypeTag,
+			ITokenFactory tokenFactory) {
+		super(ignoreTokenCount, sourceHasTypeTag, tokenFactory);
+		this.gramLength = gramLength;
+		this.usePrePost = usePrePost;
+		concreteToken = (INGramToken) token;
+	}
+
+	@Override
+	public boolean hasNext() {
+		if (gramNum < totalGrams) {
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	@Override
+	public void next() {
+		int currentTokenStart = index;
+		int tokenCount = 1;
+		int numPreChars = 0;
+		int numPostChars = 0;
+		if (usePrePost) {
+			numPreChars = Math.max(gramLength - gramNum - 1, 0);
+			numPostChars = (gramNum > totalGrams - gramLength) ? gramLength
+					- totalGrams + gramNum : 0;
+		}
+		gramNum++;
+
+		concreteToken.setNumPrePostChars(numPreChars, numPostChars);
+		if (numPreChars == 0) {
+			index += StringUtils.charSize(data, index);
+		}
+
+		// compute token count
+		// ignore pre and post grams for duplicate detection
+		if (!ignoreTokenCount && numPreChars == 0 && numPostChars == 0) {
+			int tmpIndex = start;
+			while (tmpIndex < currentTokenStart) {
+				tokenCount++; // assume found
+				int offset = 0;
+				for (int j = 0; j < gramLength; j++) {
+					if (StringUtils.toLowerCase(StringUtils.charAt(data,
+							currentTokenStart + offset)) != StringUtils
+							.toLowerCase(StringUtils.charAt(data, tmpIndex
+									+ offset))) {
+						tokenCount--;
+						break;
+					}
+					offset += StringUtils.charSize(data, tmpIndex + offset);
+				}
+				tmpIndex += StringUtils.charSize(data, tmpIndex);
+			}
+		}
+
+		// set token
+		token.reset(data, currentTokenStart, length, gramLength, tokenCount);
+	}
+
+	@Override
+	public void reset(byte[] data, int start, int length) {
+		super.reset(data, start, length);
+		gramNum = 0;
+
+		int numChars = 0;
+		int pos = index;
+		int end = pos + utf8Length;
+		while (pos < end) {
+			numChars++;
+			pos += StringUtils.charSize(data, pos);
+		}
+
+		if (usePrePost) {
+			totalGrams = numChars + gramLength - 1;
+		} else {
+			totalGrams = numChars - gramLength + 1;
+		}
+	}
+
+	public void setGramlength(int gramLength) {
+		this.gramLength = gramLength;
+	}
+
+	public void setPrePost(boolean usePrePost) {
+		this.usePrePost = usePrePost;
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8NGramToken.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8NGramToken.java
new file mode 100644
index 0000000..6b6406f
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8NGramToken.java
@@ -0,0 +1,86 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import java.io.DataOutput;
+import java.io.IOException;
+
+import edu.uci.ics.hyracks.dataflow.common.data.util.StringUtils;
+
+public class UTF8NGramToken extends AbstractUTF8Token implements INGramToken {
+
+	public final static char PRECHAR = '#';
+
+	public final static char POSTCHAR = '$';
+
+	protected int numPreChars;
+	protected int numPostChars;
+
+	public UTF8NGramToken(byte tokenTypeTag, byte countTypeTag) {
+		super(tokenTypeTag, countTypeTag);
+	}
+
+	@Override
+	public int getNumPostChars() {
+		return numPreChars;
+	}
+
+	@Override
+	public int getNumPreChars() {
+		return numPostChars;
+	}
+
+	@Override
+	public void serializeToken(DataOutput dos) throws IOException {
+		handleTokenTypeTag(dos);
+
+		// regular chars
+		int numRegChars = tokenLength - numPreChars - numPostChars;
+
+		// assuming pre and post char need 1-byte each in utf8
+		int tokenUTF8Len = getLowerCaseUTF8Len(numRegChars) + numPreChars
+				+ numPostChars;
+
+		// write utf8 length indicator
+		StringUtils.writeUTF8Len(tokenUTF8Len, dos);
+
+		// pre chars
+		for (int i = 0; i < numPreChars; i++) {
+			StringUtils.writeCharAsModifiedUTF8(PRECHAR, dos);
+		}
+
+		int pos = start;
+		for (int i = 0; i < numRegChars; i++) {
+			char c = StringUtils.toLowerCase(StringUtils.charAt(data, pos));
+			StringUtils.writeCharAsModifiedUTF8(c, dos);
+			pos += StringUtils.charSize(data, pos);
+		}
+
+		// post chars
+		for (int i = 0; i < numPostChars; i++) {
+			StringUtils.writeCharAsModifiedUTF8(POSTCHAR, dos);
+		}
+	}
+
+	public void setNumPrePostChars(int numPreChars, int numPostChars) {
+		this.numPreChars = numPreChars;
+		this.numPostChars = numPostChars;
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8NGramTokenFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8NGramTokenFactory.java
new file mode 100644
index 0000000..968d8e1
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8NGramTokenFactory.java
@@ -0,0 +1,39 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+public class UTF8NGramTokenFactory extends AbstractUTF8TokenFactory {
+
+	private static final long serialVersionUID = 1L;
+
+	public UTF8NGramTokenFactory() {
+		super();
+	}
+
+	public UTF8NGramTokenFactory(byte tokenTypeTag, byte countTypeTag) {
+		super(tokenTypeTag, countTypeTag);
+	}
+
+	@Override
+	public IToken createToken() {
+		return new UTF8NGramToken(tokenTypeTag, countTypeTag);
+	}
+
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8WordToken.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8WordToken.java
new file mode 100644
index 0000000..25e0cd3
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8WordToken.java
@@ -0,0 +1,46 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+import java.io.DataOutput;
+import java.io.IOException;
+
+import edu.uci.ics.hyracks.dataflow.common.data.util.StringUtils;
+
+public class UTF8WordToken extends AbstractUTF8Token {
+
+	public UTF8WordToken(byte tokenTypeTag, byte countTypeTag) {
+		super(tokenTypeTag, countTypeTag);
+	}
+
+	@Override
+	public void serializeToken(DataOutput dos) throws IOException {
+		handleTokenTypeTag(dos);
+
+		int tokenUTF8Len = getLowerCaseUTF8Len(tokenLength);
+		StringUtils.writeUTF8Len(tokenUTF8Len, dos);
+		int pos = start;
+		for (int i = 0; i < tokenLength; i++) {
+			char c = StringUtils.toLowerCase(StringUtils.charAt(data, pos));
+			StringUtils.writeCharAsModifiedUTF8(c, dos);
+			pos += StringUtils.charSize(data, pos);
+		}
+	}
+}
diff --git a/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8WordTokenFactory.java b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8WordTokenFactory.java
new file mode 100644
index 0000000..4358254
--- /dev/null
+++ b/hyracks-storage-am-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/UTF8WordTokenFactory.java
@@ -0,0 +1,39 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
+
+public class UTF8WordTokenFactory extends AbstractUTF8TokenFactory {
+
+	private static final long serialVersionUID = 1L;
+
+	public UTF8WordTokenFactory() {
+		super();
+	}
+
+	public UTF8WordTokenFactory(byte tokenTypeTag, byte countTypeTag) {
+		super(tokenTypeTag, countTypeTag);
+	}
+
+	@Override
+	public IToken createToken() {
+		return new UTF8WordToken(tokenTypeTag, countTypeTag);
+	}
+
+}
diff --git a/hyracks-storage-am-invertedindex/.classpath b/hyracks-storage-am-rtree/.classpath
similarity index 100%
copy from hyracks-storage-am-invertedindex/.classpath
copy to hyracks-storage-am-rtree/.classpath
diff --git a/hyracks-storage-am-invertedindex/.project b/hyracks-storage-am-rtree/.project
similarity index 91%
rename from hyracks-storage-am-invertedindex/.project
rename to hyracks-storage-am-rtree/.project
index 9303fb7..4989318 100644
--- a/hyracks-storage-am-invertedindex/.project
+++ b/hyracks-storage-am-rtree/.project
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <projectDescription>
-	<name>hyracks-storage-am-invertedindex</name>
+	<name>hyracks-storage-am-rtree</name>
 	<comment></comment>
 	<projects>
 	</projects>
diff --git a/hyracks-storage-am-rtree/.settings/org.eclipse.jdt.core.prefs b/hyracks-storage-am-rtree/.settings/org.eclipse.jdt.core.prefs
new file mode 100644
index 0000000..375e12e
--- /dev/null
+++ b/hyracks-storage-am-rtree/.settings/org.eclipse.jdt.core.prefs
@@ -0,0 +1,6 @@
+#Fri May 20 19:34:07 PDT 2011
+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
+org.eclipse.jdt.core.compiler.compliance=1.6
+org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
+org.eclipse.jdt.core.compiler.source=1.6
diff --git a/hyracks-storage-am-rtree/.settings/org.maven.ide.eclipse.prefs b/hyracks-storage-am-rtree/.settings/org.maven.ide.eclipse.prefs
new file mode 100644
index 0000000..ba4f536
--- /dev/null
+++ b/hyracks-storage-am-rtree/.settings/org.maven.ide.eclipse.prefs
@@ -0,0 +1,9 @@
+#Wed Feb 02 19:49:19 PST 2011
+activeProfiles=
+eclipse.preferences.version=1
+fullBuildGoals=process-test-resources
+includeModules=false
+resolveWorkspaceProjects=true
+resourceFilterGoals=process-resources resources\:testResources
+skipCompilerPlugin=true
+version=1
diff --git a/hyracks-storage-am-rtree/pom.xml b/hyracks-storage-am-rtree/pom.xml
new file mode 100644
index 0000000..86328f7
--- /dev/null
+++ b/hyracks-storage-am-rtree/pom.xml
@@ -0,0 +1,63 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>edu.uci.ics.hyracks</groupId>
+  <artifactId>hyracks-storage-am-rtree</artifactId>
+  <version>0.1.7-SNAPSHOT</version>
+
+  <parent>
+    <groupId>edu.uci.ics.hyracks</groupId>
+    <artifactId>hyracks</artifactId>
+    <version>0.1.7-SNAPSHOT</version>
+  </parent>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>2.0.2</version>
+        <configuration>
+          <source>1.6</source>
+          <target>1.6</target>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+  <dependencies>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-storage-am-common</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>  	
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-dataflow-common</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>  	
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-dataflow-std</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>  	
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-control-nc</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>  		
+  	<dependency>
+  		<groupId>junit</groupId>
+  		<artifactId>junit</artifactId>
+  		<version>4.8.1</version>
+  		<type>jar</type>
+  		<scope>test</scope>
+  	</dependency>  	  		
+  </dependencies>
+</project>
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/api/IRTreeFrame.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/api/IRTreeFrame.java
new file mode 100644
index 0000000..ebc17b5
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/api/IRTreeFrame.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.api;
+
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.Rectangle;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.TupleEntryArrayList;
+
+public interface IRTreeFrame extends ITreeIndexFrame {
+
+    public ITreeIndexTupleReference createTupleReference();
+
+    public void generateDist(ITupleReference tuple, TupleEntryArrayList entries, Rectangle rec, int start, int end);
+
+    public void computeMBR(ISplitKey splitKey, MultiComparator cmp);
+
+    public void insert(ITupleReference tuple, MultiComparator cmp, int tupleIndex) throws Exception;
+
+    public void delete(int tupleIndex, MultiComparator cmp) throws Exception;
+
+    public int getPageNsn();
+
+    public void setPageNsn(int pageNsn);
+
+    public int getRightPage();
+
+    public void setRightPage(int rightPage);
+
+    public void adjustMBR(ITreeIndexTupleReference[] tuples, MultiComparator cmp);
+
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/api/IRTreeInteriorFrame.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/api/IRTreeInteriorFrame.java
new file mode 100644
index 0000000..824c6b0
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/api/IRTreeInteriorFrame.java
@@ -0,0 +1,39 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.api;
+
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.PathList;
+
+public interface IRTreeInteriorFrame extends IRTreeFrame {
+
+    public boolean findBestChild(ITupleReference tuple, MultiComparator cmp);
+
+    public int getBestChildPageId(MultiComparator cmp);
+
+    public int getChildPageIdIfIntersect(ITupleReference tuple, int tupleIndex, MultiComparator cmp);
+
+    public int findTupleByPointer(ITupleReference tuple, MultiComparator cmp);
+
+    public int findTupleByPointer(ITupleReference tuple, PathList traverseList, int parentId, MultiComparator cmp);
+
+    public void adjustKey(ITupleReference tuple, int tupleIndex, MultiComparator cmp);
+
+    public boolean recomputeMBR(ITupleReference tuple, int tupleIndex, MultiComparator cmp);
+
+    public void enlarge(ITupleReference tuple, MultiComparator cmp);
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/api/IRTreeLeafFrame.java
similarity index 63%
copy from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java
copy to hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/api/IRTreeLeafFrame.java
index 38d6217..c85712d 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/api/IRTreeLeafFrame.java
@@ -13,18 +13,14 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.api;
-
-import java.nio.ByteBuffer;
+package edu.uci.ics.hyracks.storage.am.rtree.api;
 
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
 
-public interface IBTreeTupleReference extends ITupleReference {
-    public void setFieldCount(int fieldCount);
+public interface IRTreeLeafFrame extends IRTreeFrame {
 
-    public void setFieldCount(int fieldStartIndex, int fieldCount);
+    public int findTupleIndex(ITupleReference tuple, MultiComparator cmp);
 
-    public void resetByOffset(ByteBuffer buf, int tupleStartOffset);
-
-    public void resetByTupleIndex(IBTreeFrame frame, int tupleIndex);
+    public boolean intersect(ITupleReference tuple, int tupleIndex, MultiComparator cmp);
 }
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeOpHelper.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeOpHelper.java
new file mode 100644
index 0000000..5b8931d
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeOpHelper.java
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOperatorDescriptorHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexHelperOpenMode;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexOpHelper;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.freepage.LinkedListFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTree;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+
+public class RTreeOpHelper extends TreeIndexOpHelper {
+
+    protected MultiComparator interiorCmp;
+
+    public RTreeOpHelper(ITreeIndexOperatorDescriptorHelper opDesc, IHyracksStageletContext ctx, int partition,
+            IndexHelperOpenMode mode) {
+        super(opDesc, ctx, partition, mode);
+    }
+
+    public ITreeIndex createTreeIndex() throws HyracksDataException {
+        IBufferCache bufferCache = opDesc.getStorageManager().getBufferCache(ctx);
+        ITreeIndexMetaDataFrameFactory metaDataFrameFactory = new LIFOMetaDataFrameFactory();
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, indexFileId, 0,
+                metaDataFrameFactory);
+
+        return new RTree(bufferCache, freePageManager, opDesc.getTreeIndexInteriorFactory(),
+                opDesc.getTreeIndexLeafFactory(), cmp);
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeOpHelperFactory.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeOpHelperFactory.java
new file mode 100644
index 0000000..b26f21a
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeOpHelperFactory.java
@@ -0,0 +1,33 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOperatorDescriptorHelper;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexHelperOpenMode;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexOpHelper;
+
+public class RTreeOpHelperFactory implements ITreeIndexOpHelperFactory {
+
+    private static final long serialVersionUID = 1L;
+
+    @Override
+    public TreeIndexOpHelper createTreeIndexOpHelper(ITreeIndexOperatorDescriptorHelper opDesc,
+            IHyracksStageletContext ctx, int partition, IndexHelperOpenMode mode) {
+        return new RTreeOpHelper(opDesc, ctx, partition, mode);
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorDescriptor.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorDescriptor.java
new file mode 100644
index 0000000..8aab763
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorDescriptor.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.dataflow;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.job.IOperatorEnvironment;
+import edu.uci.ics.hyracks.api.job.JobSpecification;
+import edu.uci.ics.hyracks.dataflow.std.file.IFileSplitProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOpHelperFactory;
+import edu.uci.ics.hyracks.storage.common.IStorageManagerInterface;
+
+public class RTreeSearchOperatorDescriptor extends AbstractTreeIndexOperatorDescriptor {
+
+    private static final long serialVersionUID = 1L;
+
+    private int[] keyFields; // fields in input tuple to be used as keys
+
+    public RTreeSearchOperatorDescriptor(JobSpecification spec, RecordDescriptor recDesc,
+            IStorageManagerInterface storageManager, IIndexRegistryProvider<ITreeIndex> treeIndexRegistryProvider,
+            IFileSplitProvider fileSplitProvider, ITreeIndexFrameFactory interiorFrameFactory,
+            ITreeIndexFrameFactory leafFrameFactory, ITypeTrait[] typeTraits,
+            IBinaryComparatorFactory[] comparatorFactories, int[] keyFields, ITreeIndexOpHelperFactory opHelperFactory) {
+        super(spec, 1, 1, recDesc, storageManager, treeIndexRegistryProvider, fileSplitProvider, interiorFrameFactory,
+                leafFrameFactory, typeTraits, comparatorFactories, opHelperFactory);
+        this.keyFields = keyFields;
+    }
+
+    @Override
+    public IOperatorNodePushable createPushRuntime(final IHyracksStageletContext ctx, final IOperatorEnvironment env,
+            IRecordDescriptorProvider recordDescProvider, int partition, int nPartitions) {
+        return new RTreeSearchOperatorNodePushable(this, ctx, partition, recordDescProvider, keyFields);
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorNodePushable.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorNodePushable.java
new file mode 100644
index 0000000..6a13d9f
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeSearchOperatorNodePushable.java
@@ -0,0 +1,182 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.dataflow;
+
+import java.io.DataOutput;
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputUnaryOutputOperatorNodePushable;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexHelperOpenMode;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.PermutingFrameTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexOpHelper;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeInteriorFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeLeafFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTree;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTreeOpContext;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTreeSearchCursor;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.SearchPredicate;
+
+public class RTreeSearchOperatorNodePushable extends AbstractUnaryInputUnaryOutputOperatorNodePushable {
+    private TreeIndexOpHelper treeIndexOpHelper;
+    private FrameTupleAccessor accessor;
+
+    private ByteBuffer writeBuffer;
+    private FrameTupleAppender appender;
+    private ArrayTupleBuilder tb;
+    private DataOutput dos;
+
+    private RTree rtree;
+    private PermutingFrameTupleReference searchKey;
+    private SearchPredicate searchPred;
+    private MultiComparator cmp;
+    private ITreeIndexCursor cursor;
+    private ITreeIndexFrame interiorFrame;
+    private ITreeIndexFrame leafFrame;
+    private RTreeOpContext opCtx;
+
+    private RecordDescriptor recDesc;
+
+    public RTreeSearchOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc, IHyracksStageletContext ctx,
+            int partition, IRecordDescriptorProvider recordDescProvider, int[] keyFields) {
+        treeIndexOpHelper = opDesc.getTreeIndexOpHelperFactory().createTreeIndexOpHelper(opDesc, ctx, partition,
+                IndexHelperOpenMode.OPEN);
+
+        this.recDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getOperatorId(), 0);
+        if (keyFields != null && keyFields.length > 0) {
+            searchKey = new PermutingFrameTupleReference();
+            searchKey.setFieldPermutation(keyFields);
+        }
+    }
+
+    @Override
+    public void open() throws HyracksDataException {
+        AbstractTreeIndexOperatorDescriptor opDesc = (AbstractTreeIndexOperatorDescriptor) treeIndexOpHelper
+                .getOperatorDescriptor();
+        accessor = new FrameTupleAccessor(treeIndexOpHelper.getHyracksStageletContext().getFrameSize(), recDesc);
+
+        interiorFrame = opDesc.getTreeIndexInteriorFactory().createFrame();
+        leafFrame = opDesc.getTreeIndexLeafFactory().createFrame();
+        cursor = new RTreeSearchCursor((IRTreeInteriorFrame) interiorFrame, (IRTreeLeafFrame) leafFrame);
+
+        try {
+
+            treeIndexOpHelper.init();
+            rtree = (RTree) treeIndexOpHelper.getTreeIndex();
+
+            int keySearchFields = rtree.getCmp().getComparators().length;
+
+            IBinaryComparator[] keySearchComparators = new IBinaryComparator[keySearchFields];
+            for (int i = 0; i < keySearchFields; i++) {
+                keySearchComparators[i] = rtree.getCmp().getComparators()[i];
+            }
+            cmp = new MultiComparator(rtree.getCmp().getTypeTraits(), keySearchComparators);
+
+            searchPred = new SearchPredicate(searchKey, cmp);
+            accessor = new FrameTupleAccessor(treeIndexOpHelper.getHyracksStageletContext().getFrameSize(), recDesc);
+
+            writeBuffer = treeIndexOpHelper.getHyracksStageletContext().allocateFrame();
+            tb = new ArrayTupleBuilder(rtree.getCmp().getFieldCount());
+            dos = tb.getDataOutput();
+            appender = new FrameTupleAppender(treeIndexOpHelper.getHyracksStageletContext().getFrameSize());
+            appender.reset(writeBuffer, true);
+
+            opCtx = rtree.createOpContext(IndexOp.SEARCH, treeIndexOpHelper.getLeafFrame(),
+                    treeIndexOpHelper.getInteriorFrame(), null);
+
+        } catch (Exception e) {
+            treeIndexOpHelper.deinit();
+        }
+    }
+
+    private void writeSearchResults() throws Exception {
+        while (cursor.hasNext()) {
+            tb.reset();
+            cursor.next();
+
+            ITupleReference frameTuple = cursor.getTuple();
+            for (int i = 0; i < frameTuple.getFieldCount(); i++) {
+                dos.write(frameTuple.getFieldData(i), frameTuple.getFieldStart(i), frameTuple.getFieldLength(i));
+                tb.addFieldEndOffset();
+            }
+
+            if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
+                FrameUtils.flushFrame(writeBuffer, writer);
+                appender.reset(writeBuffer, true);
+                if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
+                    throw new IllegalStateException();
+                }
+            }
+        }
+    }
+
+    @Override
+    public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
+        accessor.reset(buffer);
+
+        int tupleCount = accessor.getTupleCount();
+        try {
+            for (int i = 0; i < tupleCount; i++) {
+                searchKey.reset(accessor, i);
+
+                searchPred.setSearchKey(searchKey);
+                cursor.reset();
+                rtree.search(cursor, searchPred, opCtx);
+                writeSearchResults();
+            }
+        } catch (Exception e) {
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void close() throws HyracksDataException {
+        try {
+            if (appender.getTupleCount() > 0) {
+                FrameUtils.flushFrame(writeBuffer, writer);
+            }
+            writer.close();
+            try {
+                cursor.close();
+            } catch (Exception e) {
+                throw new HyracksDataException(e);
+            }
+        } finally {
+            treeIndexOpHelper.deinit();
+        }
+    }
+
+    @Override
+    public void flush() throws HyracksDataException {
+        if (appender.getTupleCount() > 0) {
+            FrameUtils.flushFrame(writeBuffer, writer);
+        }
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMFrame.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMFrame.java
new file mode 100644
index 0000000..17c10e5
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMFrame.java
@@ -0,0 +1,206 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.frames;
+
+import java.util.ArrayList;
+
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.frames.TreeIndexNSMFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTreeSplitKey;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.Rectangle;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.TupleEntryArrayList;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.UnorderedSlotManager;
+import edu.uci.ics.hyracks.storage.am.rtree.tuples.RTreeTypeAwareTupleWriter;
+
+public abstract class RTreeNSMFrame extends TreeIndexNSMFrame implements IRTreeFrame {
+    protected static final int pageNsnOff = smFlagOff + 1;
+    protected static final int rightPageOff = pageNsnOff + 4;
+
+    protected ITreeIndexTupleReference[] tuples;
+    protected ITreeIndexTupleReference cmpFrameTuple;
+    protected TupleEntryArrayList tupleEntries1; // used for split and checking
+                                                 // enlargement
+    protected TupleEntryArrayList tupleEntries2; // used for split
+
+    protected Rectangle[] rec;
+
+    protected static final double splitFactor = 0.4;
+    protected static final int nearMinimumOverlapFactor = 32;
+    private static final double doubleEpsilon = computeDoubleEpsilon();
+    private static final int numTuplesEntries = 100;
+
+    public RTreeNSMFrame(ITreeIndexTupleWriter tupleWriter, int keyFieldCount) {
+        super(tupleWriter, new UnorderedSlotManager());
+        this.tuples = new ITreeIndexTupleReference[keyFieldCount];
+        for (int i = 0; i < keyFieldCount; i++) {
+            this.tuples[i] = tupleWriter.createTupleReference();
+        }
+        cmpFrameTuple = tupleWriter.createTupleReference();
+
+        tupleEntries1 = new TupleEntryArrayList(numTuplesEntries, numTuplesEntries);
+        tupleEntries2 = new TupleEntryArrayList(numTuplesEntries, numTuplesEntries);
+        rec = new Rectangle[4];
+        for (int i = 0; i < 4; i++) {
+            rec[i] = new Rectangle(keyFieldCount / 2);
+        }
+    }
+
+    private static double computeDoubleEpsilon() {
+        double doubleEpsilon = 1.0;
+
+        do {
+            doubleEpsilon /= 2.0;
+        } while (1.0 + (doubleEpsilon / 2.0) != 1.0);
+        return doubleEpsilon;
+    }
+
+    public static double doubleEpsilon() {
+        return doubleEpsilon;
+    }
+
+    @Override
+    public void initBuffer(byte level) {
+        super.initBuffer(level);
+        buf.putInt(pageNsnOff, 0);
+        buf.putInt(rightPageOff, -1);
+    }
+
+    public void setTupleCount(int tupleCount) {
+        buf.putInt(tupleCountOff, tupleCount);
+    }
+
+    @Override
+    public void setPageNsn(int pageNsn) {
+        buf.putInt(pageNsnOff, pageNsn);
+    }
+
+    @Override
+    public int getPageNsn() {
+        return buf.getInt(pageNsnOff);
+    }
+
+    @Override
+    protected void resetSpaceParams() {
+        buf.putInt(freeSpaceOff, rightPageOff + 4);
+        buf.putInt(totalFreeSpaceOff, buf.capacity() - (rightPageOff + 4));
+    }
+
+    @Override
+    public int getRightPage() {
+        return buf.getInt(rightPageOff);
+    }
+
+    @Override
+    public void setRightPage(int rightPage) {
+        buf.putInt(rightPageOff, rightPage);
+    }
+
+    protected ITreeIndexTupleReference[] getTuples() {
+        return tuples;
+    }
+
+    // for debugging
+    public ArrayList<Integer> getChildren(MultiComparator cmp) {
+        ArrayList<Integer> ret = new ArrayList<Integer>();
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+        int tupleCount = buf.getInt(tupleCountOff);
+        for (int i = 0; i < tupleCount; i++) {
+            int tupleOff = slotManager.getTupleOff(slotManager.getSlotOff(i));
+            frameTuple.resetByTupleOffset(buf, tupleOff);
+
+            int intVal = IntegerSerializerDeserializer.getInt(
+                    buf.array(),
+                    frameTuple.getFieldStart(frameTuple.getFieldCount() - 1)
+                            + frameTuple.getFieldLength(frameTuple.getFieldCount() - 1));
+            ret.add(intVal);
+        }
+        return ret;
+    }
+
+    public void generateDist(ITupleReference tuple, TupleEntryArrayList entries, Rectangle rec, int start, int end) {
+        int j = 0;
+        while (entries.get(j).getTupleIndex() == -1) {
+            j++;
+        }
+        frameTuple.resetByTupleIndex(this, entries.get(j).getTupleIndex());
+        rec.set(frameTuple);
+        for (int i = start; i < end; ++i) {
+            if (i != j) {
+                if (entries.get(i).getTupleIndex() != -1) {
+                    frameTuple.resetByTupleIndex(this, entries.get(i).getTupleIndex());
+                    rec.enlarge(frameTuple);
+                } else {
+                    rec.enlarge(tuple);
+                }
+            }
+        }
+    }
+
+    @Override
+    public ITreeIndexTupleReference createTupleReference() {
+        return tupleWriter.createTupleReference();
+    }
+
+    public void adjustMBRImpl(ITreeIndexTupleReference[] tuples, MultiComparator cmp) {
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 1; i < getTupleCount(); i++) {
+            frameTuple.resetByTupleIndex(this, i);
+            for (int j = 0; j < maxFieldPos; j++) {
+                int k = maxFieldPos + j;
+                int c = cmp.getComparators()[j].compare(frameTuple.getFieldData(j), frameTuple.getFieldStart(j),
+                        frameTuple.getFieldLength(j), tuples[j].getFieldData(j), tuples[j].getFieldStart(j),
+                        tuples[j].getFieldLength(j));
+                if (c < 0) {
+                    tuples[j].resetByTupleIndex(this, i);
+                }
+                c = cmp.getComparators()[k].compare(frameTuple.getFieldData(k), frameTuple.getFieldStart(k),
+                        frameTuple.getFieldLength(k), tuples[k].getFieldData(k), tuples[k].getFieldStart(k),
+                        tuples[k].getFieldLength(k));
+                if (c > 0) {
+                    tuples[k].resetByTupleIndex(this, i);
+                }
+            }
+        }
+    }
+
+    @Override
+    public void computeMBR(ISplitKey splitKey, MultiComparator cmp) {
+        RTreeSplitKey rTreeSplitKey = ((RTreeSplitKey) splitKey);
+        RTreeTypeAwareTupleWriter rTreeTupleWriterLeftFrame = ((RTreeTypeAwareTupleWriter) tupleWriter);
+        frameTuple.setFieldCount(cmp.getFieldCount());
+
+        int tupleOff = slotManager.getTupleOff(slotManager.getSlotEndOff());
+        frameTuple.resetByTupleOffset(buf, tupleOff);
+        int splitKeySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
+
+        splitKey.initData(splitKeySize);
+        this.adjustMBR(tuples, cmp);
+        rTreeTupleWriterLeftFrame.writeTupleFields(tuples, 0, rTreeSplitKey.getLeftPageBuffer(), 0);
+        rTreeSplitKey.getLeftTuple().resetByTupleOffset(rTreeSplitKey.getLeftPageBuffer(), 0);
+    }
+
+    @Override
+    public int getPageHeaderSize() {
+        return rightPageOff;
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMInteriorFrame.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMInteriorFrame.java
new file mode 100644
index 0000000..d03c5e9
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMInteriorFrame.java
@@ -0,0 +1,645 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.frames;
+
+import java.io.ByteArrayInputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.util.ArrayList;
+import java.util.Collections;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.DoubleSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.frames.FrameOpSpaceStatus;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.SlotOffTupleOff;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeInteriorFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.EntriesOrder;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.PathList;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTreeSplitKey;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.UnorderedSlotManager;
+import edu.uci.ics.hyracks.storage.am.rtree.tuples.RTreeTypeAwareTupleWriter;
+
+public class RTreeNSMInteriorFrame extends RTreeNSMFrame implements IRTreeInteriorFrame {
+
+    private static final int childPtrSize = 4;
+
+    public RTreeNSMInteriorFrame(ITreeIndexTupleWriter tupleWriter, int keyFieldCount) {
+        super(tupleWriter, keyFieldCount);
+    }
+
+    @Override
+    public String printKeys(MultiComparator cmp, ISerializerDeserializer[] fields) throws HyracksDataException {
+        StringBuilder strBuilder = new StringBuilder();
+        int tupleCount = buf.getInt(tupleCountOff);
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+        for (int i = 0; i < tupleCount; i++) {
+            frameTuple.resetByTupleIndex(this, i);
+            for (int j = 0; j < cmp.getKeyFieldCount(); j++) {
+                ByteArrayInputStream inStream = new ByteArrayInputStream(frameTuple.getFieldData(j),
+                        frameTuple.getFieldStart(j), frameTuple.getFieldLength(j));
+                DataInput dataIn = new DataInputStream(inStream);
+                Object o = fields[j].deserialize(dataIn);
+                strBuilder.append(o.toString() + " ");
+            }
+            strBuilder.append(" | ");
+        }
+        strBuilder.append("\n");
+        return strBuilder.toString();
+    }
+
+    @Override
+    public boolean findBestChild(ITupleReference tuple, MultiComparator cmp) {
+        cmpFrameTuple.setFieldCount(cmp.getKeyFieldCount());
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+
+        int bestChild = 0;
+        double minEnlargedArea = Double.MAX_VALUE;
+
+        // the children pointers in the node point to leaves
+        if (getLevel() == 1) {
+            // find least overlap enlargement, use minimum enlarged area to
+            // break tie, if tie still exists use minimum area to break it
+            for (int i = 0; i < getTupleCount(); ++i) {
+                frameTuple.resetByTupleIndex(this, i);
+                double enlargedArea = enlargedArea(frameTuple, tuple, cmp);
+                tupleEntries1.add(i, enlargedArea);
+                if (enlargedArea < minEnlargedArea) {
+                    minEnlargedArea = enlargedArea;
+                    bestChild = i;
+                }
+            }
+            if (minEnlargedArea < RTreeNSMFrame.doubleEpsilon() || minEnlargedArea > RTreeNSMFrame.doubleEpsilon()) {
+                minEnlargedArea = Double.MAX_VALUE;
+                int k;
+                if (getTupleCount() > nearMinimumOverlapFactor) {
+                    // sort the entries based on their area enlargement needed
+                    // to include the object
+                    tupleEntries1.sort(EntriesOrder.ASCENDING, getTupleCount());
+                    k = nearMinimumOverlapFactor;
+                } else {
+                    k = getTupleCount();
+                }
+
+                double minOverlap = Double.MAX_VALUE;
+                int id = 0;
+                for (int i = 0; i < k; ++i) {
+                    double difference = 0.0;
+                    for (int j = 0; j < getTupleCount(); ++j) {
+                        frameTuple.resetByTupleIndex(this, j);
+                        cmpFrameTuple.resetByTupleIndex(this, tupleEntries1.get(i).getTupleIndex());
+
+                        int c = pointerCmp(frameTuple, cmpFrameTuple, cmp);
+                        if (c != 0) {
+                            double intersection = overlappedArea(frameTuple, tuple, cmpFrameTuple, cmp);
+                            if (intersection != 0.0) {
+                                difference += intersection - overlappedArea(frameTuple, null, cmpFrameTuple, cmp);
+                            }
+                        } else {
+                            id = j;
+                        }
+                    }
+
+                    double enlargedArea = enlargedArea(cmpFrameTuple, tuple, cmp);
+                    if (difference < minOverlap) {
+                        minOverlap = difference;
+                        minEnlargedArea = enlargedArea;
+                        bestChild = id;
+                    } else if (difference == minOverlap) {
+                        if (enlargedArea < minEnlargedArea) {
+                            minEnlargedArea = enlargedArea;
+                            bestChild = id;
+                        } else if (enlargedArea == minEnlargedArea) {
+                            double area = area(cmpFrameTuple, cmp);
+                            frameTuple.resetByTupleIndex(this, bestChild);
+                            double minArea = area(frameTuple, cmp);
+                            if (area < minArea) {
+                                bestChild = id;
+                            }
+                        }
+                    }
+                }
+            }
+        } else { // find minimum enlarged area, use minimum area to break tie
+            for (int i = 0; i < getTupleCount(); i++) {
+                frameTuple.resetByTupleIndex(this, i);
+                double enlargedArea = enlargedArea(frameTuple, tuple, cmp);
+                if (enlargedArea < minEnlargedArea) {
+                    minEnlargedArea = enlargedArea;
+                    bestChild = i;
+                } else if (enlargedArea == minEnlargedArea) {
+                    double area = area(frameTuple, cmp);
+                    frameTuple.resetByTupleIndex(this, bestChild);
+                    double minArea = area(frameTuple, cmp);
+                    if (area < minArea) {
+                        bestChild = i;
+                    }
+                }
+            }
+        }
+        tupleEntries1.clear();
+
+        frameTuple.resetByTupleIndex(this, bestChild);
+        if (minEnlargedArea > 0.0) {
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    @Override
+    public int getBestChildPageId(MultiComparator cmp) {
+        return buf.getInt(getChildPointerOff(frameTuple, cmp));
+    }
+
+    @Override
+    public int findTupleByPointer(ITupleReference tuple, MultiComparator cmp) {
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+        for (int i = 0; i < getTupleCount(); i++) {
+            frameTuple.resetByTupleIndex(this, i);
+            int c = pointerCmp(frameTuple, tuple, cmp);
+            if (c == 0) {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    @Override
+    public int getChildPageIdIfIntersect(ITupleReference tuple, int tupleIndex, MultiComparator cmp) {
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+        frameTuple.resetByTupleIndex(this, tupleIndex);
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < maxFieldPos; i++) {
+            int j = maxFieldPos + i;
+            int c = cmp.getComparators()[i].compare(tuple.getFieldData(i), tuple.getFieldStart(i),
+                    tuple.getFieldLength(i), frameTuple.getFieldData(j), frameTuple.getFieldStart(j),
+                    frameTuple.getFieldLength(j));
+            if (c > 0) {
+                return -1;
+            }
+            c = cmp.getComparators()[i].compare(tuple.getFieldData(j), tuple.getFieldStart(j), tuple.getFieldLength(j),
+                    frameTuple.getFieldData(i), frameTuple.getFieldStart(i), frameTuple.getFieldLength(i));
+            if (c < 0) {
+                return -1;
+            }
+        }
+        // return buf.getInt(frameTuple.getFieldStart(cmp.getKeyFieldCount()));
+        return buf.getInt(getChildPointerOff(frameTuple, cmp));
+    }
+
+    @Override
+    public int findTupleByPointer(ITupleReference tuple, PathList traverseList, int parentIndex, MultiComparator cmp) {
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+        for (int i = 0; i < getTupleCount(); i++) {
+            frameTuple.resetByTupleIndex(this, i);
+
+            int c = pointerCmp(frameTuple, tuple, cmp);
+            if (c == 0) {
+                return i;
+            } else {
+                int pageId = IntegerSerializerDeserializer.getInt(frameTuple.getFieldData(cmp.getKeyFieldCount() - 1),
+                        getChildPointerOff(frameTuple, cmp));
+                traverseList.add(pageId, -1, parentIndex);
+            }
+        }
+        return -1;
+    }
+
+    @Override
+    public boolean compact(MultiComparator cmp) {
+        resetSpaceParams();
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+
+        int tupleCount = buf.getInt(tupleCountOff);
+        int freeSpace = buf.getInt(freeSpaceOff);
+
+        ArrayList<SlotOffTupleOff> sortedTupleOffs = new ArrayList<SlotOffTupleOff>();
+        sortedTupleOffs.ensureCapacity(tupleCount);
+        for (int i = 0; i < tupleCount; i++) {
+            int slotOff = slotManager.getSlotOff(i);
+            int tupleOff = slotManager.getTupleOff(slotOff);
+            sortedTupleOffs.add(new SlotOffTupleOff(i, slotOff, tupleOff));
+        }
+        Collections.sort(sortedTupleOffs);
+
+        for (int i = 0; i < sortedTupleOffs.size(); i++) {
+            int tupleOff = sortedTupleOffs.get(i).tupleOff;
+            frameTuple.resetByTupleOffset(buf, tupleOff);
+
+            int tupleEndOff = frameTuple.getFieldStart(frameTuple.getFieldCount() - 1)
+                    + frameTuple.getFieldLength(frameTuple.getFieldCount() - 1);
+            int tupleLength = tupleEndOff - tupleOff + childPtrSize;
+            System.arraycopy(buf.array(), tupleOff, buf.array(), freeSpace, tupleLength);
+
+            slotManager.setSlot(sortedTupleOffs.get(i).slotOff, freeSpace);
+            freeSpace += tupleLength;
+        }
+
+        buf.putInt(freeSpaceOff, freeSpace);
+        buf.putInt(totalFreeSpaceOff, buf.capacity() - freeSpace - tupleCount * slotManager.getSlotSize());
+
+        return false;
+    }
+
+    @Override
+    public FrameOpSpaceStatus hasSpaceInsert(ITupleReference tuple, MultiComparator cmp) {
+        int bytesRequired = tupleWriter.bytesRequired(tuple) + childPtrSize; // for
+                                                                             // the
+                                                                             // child
+                                                                             // pointer
+        if (bytesRequired + slotManager.getSlotSize() <= buf.capacity() - buf.getInt(freeSpaceOff)
+                - (buf.getInt(tupleCountOff) * slotManager.getSlotSize()))
+            return FrameOpSpaceStatus.SUFFICIENT_CONTIGUOUS_SPACE;
+        else if (bytesRequired + slotManager.getSlotSize() <= buf.getInt(totalFreeSpaceOff))
+            return FrameOpSpaceStatus.SUFFICIENT_SPACE;
+        else
+            return FrameOpSpaceStatus.INSUFFICIENT_SPACE;
+    }
+
+    @Override
+    public void adjustKey(ITupleReference tuple, int tupleIndex, MultiComparator cmp) {
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+        if (tupleIndex == -1) {
+            tupleIndex = findTupleByPointer(tuple, cmp);
+        }
+        if (tupleIndex != -1) {
+            tupleWriter.writeTuple(tuple, buf, getTupleOffset(tupleIndex));
+        }
+    }
+
+    private int pointerCmp(ITupleReference tupleA, ITupleReference tupleB, MultiComparator cmp) {
+        return cmp.getIntCmp().compare(tupleA.getFieldData(cmp.getKeyFieldCount() - 1),
+                getChildPointerOff(tupleA, cmp), childPtrSize, tupleB.getFieldData(cmp.getKeyFieldCount() - 1),
+                getChildPointerOff(tupleB, cmp), childPtrSize);
+    }
+
+    @Override
+    public int split(ITreeIndexFrame rightFrame, ITupleReference tuple, MultiComparator cmp, ISplitKey splitKey)
+            throws Exception {
+
+        rightFrame.setPageTupleFieldCount(cmp.getKeyFieldCount());
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+
+        RTreeSplitKey rTreeSplitKey = ((RTreeSplitKey) splitKey);
+        RTreeTypeAwareTupleWriter rTreeTupleWriterLeftFrame = ((RTreeTypeAwareTupleWriter) tupleWriter);
+        RTreeTypeAwareTupleWriter rTreeTupleWriterRightFrame = ((RTreeTypeAwareTupleWriter) rightFrame.getTupleWriter());
+
+        // calculations are based on the R*-tree paper
+        int m = (int) Math.floor((getTupleCount() + 1) * splitFactor);
+        int splitDistribution = getTupleCount() - (2 * m) + 2;
+
+        // to calculate the minimum margin in order to pick the split axis
+        double minMargin = Double.MAX_VALUE;
+        int splitAxis = 0, sortOrder = 0;
+
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < maxFieldPos; i++) {
+            int j = maxFieldPos + i;
+            for (int k = 0; k < getTupleCount(); ++k) {
+
+                frameTuple.resetByTupleIndex(this, k);
+
+                double LowerKey = DoubleSerializerDeserializer.getDouble(frameTuple.getFieldData(i),
+                        frameTuple.getFieldStart(i));
+                double UpperKey = DoubleSerializerDeserializer.getDouble(frameTuple.getFieldData(j),
+                        frameTuple.getFieldStart(j));
+
+                tupleEntries1.add(k, LowerKey);
+                tupleEntries2.add(k, UpperKey);
+            }
+            double LowerKey = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(i), tuple.getFieldStart(i));
+            double UpperKey = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(j), tuple.getFieldStart(j));
+
+            tupleEntries1.add(-1, LowerKey);
+            tupleEntries2.add(-1, UpperKey);
+
+            tupleEntries1.sort(EntriesOrder.ASCENDING, getTupleCount() + 1);
+            tupleEntries2.sort(EntriesOrder.ASCENDING, getTupleCount() + 1);
+
+            double lowerMargin = 0.0, upperMargin = 0.0;
+            // generate distribution
+            for (int k = 1; k <= splitDistribution; ++k) {
+                int d = m - 1 + k;
+
+                generateDist(tuple, tupleEntries1, rec[0], 0, d);
+                generateDist(tuple, tupleEntries2, rec[1], 0, d);
+                generateDist(tuple, tupleEntries1, rec[2], d, getTupleCount() + 1);
+                generateDist(tuple, tupleEntries2, rec[3], d, getTupleCount() + 1);
+
+                // calculate the margin of the distributions
+                lowerMargin += rec[0].margin() + rec[2].margin();
+                upperMargin += rec[1].margin() + rec[3].margin();
+            }
+            double margin = Math.min(lowerMargin, upperMargin);
+
+            // store minimum margin as split axis
+            if (margin < minMargin) {
+                minMargin = margin;
+                splitAxis = i;
+                sortOrder = (lowerMargin < upperMargin) ? 0 : 2;
+            }
+
+            tupleEntries1.clear();
+            tupleEntries2.clear();
+        }
+
+        for (int i = 0; i < getTupleCount(); ++i) {
+            frameTuple.resetByTupleIndex(this, i);
+            double key = DoubleSerializerDeserializer.getDouble(frameTuple.getFieldData(splitAxis + sortOrder),
+                    frameTuple.getFieldStart(splitAxis + sortOrder));
+            tupleEntries1.add(i, key);
+        }
+        double key = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(splitAxis + sortOrder),
+                tuple.getFieldStart(splitAxis + sortOrder));
+        tupleEntries1.add(-1, key);
+        tupleEntries1.sort(EntriesOrder.ASCENDING, getTupleCount() + 1);
+
+        double minArea = Double.MAX_VALUE;
+        double minOverlap = Double.MAX_VALUE;
+        int splitPoint = 0;
+        for (int i = 1; i <= splitDistribution; ++i) {
+            int d = m - 1 + i;
+
+            generateDist(tuple, tupleEntries1, rec[0], 0, d);
+            generateDist(tuple, tupleEntries1, rec[2], d, getTupleCount() + 1);
+
+            double overlap = rec[0].overlappedArea(rec[2]);
+            if (overlap < minOverlap) {
+                splitPoint = d;
+                minOverlap = overlap;
+                minArea = rec[0].area() + rec[2].area();
+            } else if (overlap == minOverlap) {
+                double area = rec[0].area() + rec[2].area();
+                if (area < minArea) {
+                    splitPoint = d;
+                    minArea = area;
+                }
+            }
+        }
+        int startIndex, endIndex;
+        if (splitPoint < (getTupleCount() + 1) / 2) {
+            startIndex = 0;
+            endIndex = splitPoint;
+        } else {
+            startIndex = splitPoint;
+            endIndex = (getTupleCount() + 1);
+        }
+        boolean tupleInserted = false;
+        int totalBytes = 0, numOfDeletedTuples = 0;
+        for (int i = startIndex; i < endIndex; i++) {
+            if (tupleEntries1.get(i).getTupleIndex() != -1) {
+                frameTuple.resetByTupleIndex(this, tupleEntries1.get(i).getTupleIndex());
+                rightFrame.insert(frameTuple, cmp, -1);
+                ((UnorderedSlotManager) slotManager).modifySlot(
+                        slotManager.getSlotOff(tupleEntries1.get(i).getTupleIndex()), -1);
+                totalBytes += tupleWriter.bytesRequired(frameTuple) + childPtrSize;
+                numOfDeletedTuples++;
+            } else {
+                rightFrame.insert(tuple, cmp, -1);
+                tupleInserted = true;
+            }
+        }
+
+        ((UnorderedSlotManager) slotManager).deleteEmptySlots();
+
+        // maintain space information
+        buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) + totalBytes
+                + (slotManager.getSlotSize() * numOfDeletedTuples));
+
+        // compact both pages
+        rightFrame.compact(cmp);
+        compact(cmp);
+
+        if (!tupleInserted) {
+            insert(tuple, cmp, -1);
+        }
+
+        int tupleOff = slotManager.getTupleOff(slotManager.getSlotEndOff());
+        frameTuple.resetByTupleOffset(buf, tupleOff);
+        int splitKeySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
+
+        splitKey.initData(splitKeySize);
+        this.adjustMBR(tuples, cmp);
+        rTreeTupleWriterLeftFrame.writeTupleFields(tuples, 0, rTreeSplitKey.getLeftPageBuffer(), 0);
+        rTreeSplitKey.getLeftTuple().resetByTupleOffset(rTreeSplitKey.getLeftPageBuffer(), 0);
+
+        ((IRTreeFrame) rightFrame).adjustMBR(((RTreeNSMFrame) rightFrame).getTuples(), cmp);
+        rTreeTupleWriterRightFrame.writeTupleFields(((RTreeNSMFrame) rightFrame).getTuples(), 0,
+                rTreeSplitKey.getRightPageBuffer(), 0);
+        rTreeSplitKey.getRightTuple().resetByTupleOffset(rTreeSplitKey.getRightPageBuffer(), 0);
+
+        tupleEntries1.clear();
+        tupleEntries2.clear();
+        return 0;
+    }
+
+    private int getChildPointerOff(ITupleReference tuple, MultiComparator cmp) {
+        return tuple.getFieldStart(cmp.getKeyFieldCount() - 1) + tuple.getFieldLength(cmp.getKeyFieldCount() - 1);
+    }
+
+    @Override
+    public void insert(ITupleReference tuple, MultiComparator cmp, int tupleIndex) throws Exception {
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+        slotManager.insertSlot(-1, buf.getInt(freeSpaceOff));
+        int freeSpace = buf.getInt(freeSpaceOff);
+        int bytesWritten = tupleWriter.writeTupleFields(tuple, 0, cmp.getKeyFieldCount(), buf, freeSpace);
+        System.arraycopy(tuple.getFieldData(cmp.getKeyFieldCount() - 1), getChildPointerOff(tuple, cmp), buf.array(),
+                freeSpace + bytesWritten, childPtrSize);
+        int tupleSize = bytesWritten + childPtrSize;
+
+        buf.putInt(tupleCountOff, buf.getInt(tupleCountOff) + 1);
+        buf.putInt(freeSpaceOff, buf.getInt(freeSpaceOff) + tupleSize);
+        buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) - tupleSize - slotManager.getSlotSize());
+
+    }
+
+    @Override
+    public void delete(int tupleIndex, MultiComparator cmp) throws Exception {
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+        int slotOff = slotManager.getSlotOff(tupleIndex);
+
+        int tupleOff = slotManager.getTupleOff(slotOff);
+        frameTuple.resetByTupleOffset(buf, tupleOff);
+        int tupleSize = tupleWriter.bytesRequired(frameTuple);
+
+        // perform deletion (we just do a memcpy to overwrite the slot)
+        int slotStartOff = slotManager.getSlotEndOff();
+        int length = slotOff - slotStartOff;
+        System.arraycopy(buf.array(), slotStartOff, buf.array(), slotStartOff + slotManager.getSlotSize(), length);
+
+        // maintain space information
+        buf.putInt(tupleCountOff, buf.getInt(tupleCountOff) - 1);
+        buf.putInt(totalFreeSpaceOff,
+                buf.getInt(totalFreeSpaceOff) + tupleSize + childPtrSize + slotManager.getSlotSize());
+    }
+
+    @Override
+    public boolean recomputeMBR(ITupleReference tuple, int tupleIndex, MultiComparator cmp) {
+        frameTuple.setFieldCount(cmp.getKeyFieldCount());
+        frameTuple.resetByTupleIndex(this, tupleIndex);
+
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < maxFieldPos; i++) {
+            int j = maxFieldPos + i;
+            int c = cmp.getComparators()[i].compare(frameTuple.getFieldData(i), frameTuple.getFieldStart(i),
+                    frameTuple.getFieldLength(i), tuple.getFieldData(i), tuple.getFieldStart(i),
+                    tuple.getFieldLength(i));
+            if (c != 0) {
+                return true;
+            }
+            c = cmp.getComparators()[j].compare(frameTuple.getFieldData(j), frameTuple.getFieldStart(j),
+                    frameTuple.getFieldLength(j), tuple.getFieldData(j), tuple.getFieldStart(j),
+                    tuple.getFieldLength(j));
+
+            if (c != 0) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private double overlappedArea(ITupleReference tuple1, ITupleReference tupleToBeInserted, ITupleReference tuple2,
+            MultiComparator cmp) {
+        double area = 1.0;
+        double f1, f2;
+
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < maxFieldPos; i++) {
+            int j = maxFieldPos + i;
+            double pHigh1, pLow1;
+            if (tupleToBeInserted != null) {
+                int c = cmp.getComparators()[i].compare(tuple1.getFieldData(i), tuple1.getFieldStart(i),
+                        tuple1.getFieldLength(i), tupleToBeInserted.getFieldData(i),
+                        tupleToBeInserted.getFieldStart(i), tupleToBeInserted.getFieldLength(i));
+                if (c < 0) {
+                    pLow1 = DoubleSerializerDeserializer.getDouble(tuple1.getFieldData(i), tuple1.getFieldStart(i));
+                } else {
+                    pLow1 = DoubleSerializerDeserializer.getDouble(tupleToBeInserted.getFieldData(i),
+                            tupleToBeInserted.getFieldStart(i));
+                }
+
+                c = cmp.getComparators()[j].compare(tuple1.getFieldData(j), tuple1.getFieldStart(j),
+                        tuple1.getFieldLength(j), tupleToBeInserted.getFieldData(j),
+                        tupleToBeInserted.getFieldStart(j), tupleToBeInserted.getFieldLength(j));
+                if (c > 0) {
+                    pHigh1 = DoubleSerializerDeserializer.getDouble(tuple1.getFieldData(j), tuple1.getFieldStart(j));
+                } else {
+                    pHigh1 = DoubleSerializerDeserializer.getDouble(tupleToBeInserted.getFieldData(j),
+                            tupleToBeInserted.getFieldStart(j));
+                }
+            } else {
+                pLow1 = DoubleSerializerDeserializer.getDouble(tuple1.getFieldData(i), tuple1.getFieldStart(i));
+                pHigh1 = DoubleSerializerDeserializer.getDouble(tuple1.getFieldData(j), tuple1.getFieldStart(j));
+            }
+
+            double pLow2 = DoubleSerializerDeserializer.getDouble(tuple2.getFieldData(i), tuple2.getFieldStart(i));
+            double pHigh2 = DoubleSerializerDeserializer.getDouble(tuple2.getFieldData(j), tuple2.getFieldStart(j));
+
+            if (pLow1 > pHigh2 || pHigh1 < pLow2) {
+                return 0.0;
+            }
+
+            f1 = Math.max(pLow1, pLow2);
+            f2 = Math.min(pHigh1, pHigh2);
+            area *= f2 - f1;
+        }
+        return area;
+    }
+
+    private double enlargedArea(ITupleReference tuple, ITupleReference tupleToBeInserted, MultiComparator cmp) {
+        double areaBeforeEnlarge = area(tuple, cmp);
+        double areaAfterEnlarge = 1.0;
+
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < maxFieldPos; i++) {
+            int j = maxFieldPos + i;
+            double pHigh, pLow;
+            int c = cmp.getComparators()[i].compare(tuple.getFieldData(i), tuple.getFieldStart(i),
+                    tuple.getFieldLength(i), tupleToBeInserted.getFieldData(i), tupleToBeInserted.getFieldStart(i),
+                    tupleToBeInserted.getFieldLength(i));
+            if (c < 0) {
+                pLow = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(i), tuple.getFieldStart(i));
+            } else {
+                pLow = DoubleSerializerDeserializer.getDouble(tupleToBeInserted.getFieldData(i),
+                        tupleToBeInserted.getFieldStart(i));
+            }
+
+            c = cmp.getComparators()[j].compare(tuple.getFieldData(j), tuple.getFieldStart(j), tuple.getFieldLength(j),
+                    tupleToBeInserted.getFieldData(j), tupleToBeInserted.getFieldStart(j),
+                    tupleToBeInserted.getFieldLength(j));
+            if (c > 0) {
+                pHigh = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(j), tuple.getFieldStart(j));
+            } else {
+                pHigh = DoubleSerializerDeserializer.getDouble(tupleToBeInserted.getFieldData(j),
+                        tupleToBeInserted.getFieldStart(j));
+            }
+            areaAfterEnlarge *= pHigh - pLow;
+        }
+        return areaAfterEnlarge - areaBeforeEnlarge;
+    }
+
+    private double area(ITupleReference tuple, MultiComparator cmp) {
+        double area = 1.0;
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < maxFieldPos; i++) {
+            int j = maxFieldPos + i;
+            area *= DoubleSerializerDeserializer.getDouble(tuple.getFieldData(j), tuple.getFieldStart(j))
+                    - DoubleSerializerDeserializer.getDouble(tuple.getFieldData(i), tuple.getFieldStart(i));
+        }
+        return area;
+    }
+
+    @Override
+    public void enlarge(ITupleReference tuple, MultiComparator cmp) {
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < maxFieldPos; i++) {
+            int j = maxFieldPos + i;
+            int c = cmp.getComparators()[i].compare(frameTuple.getFieldData(i), frameTuple.getFieldStart(i),
+                    frameTuple.getFieldLength(i), tuple.getFieldData(i), tuple.getFieldStart(i),
+                    tuple.getFieldLength(i));
+            if (c > 0) {
+                System.arraycopy(tuple.getFieldData(i), tuple.getFieldStart(i), frameTuple.getFieldData(i),
+                        frameTuple.getFieldStart(i), tuple.getFieldLength(i));
+            }
+            c = cmp.getComparators()[j].compare(frameTuple.getFieldData(j), frameTuple.getFieldStart(j),
+                    frameTuple.getFieldLength(j), tuple.getFieldData(j), tuple.getFieldStart(j),
+                    tuple.getFieldLength(j));
+            if (c < 0) {
+                System.arraycopy(tuple.getFieldData(j), tuple.getFieldStart(j), frameTuple.getFieldData(j),
+                        frameTuple.getFieldStart(j), tuple.getFieldLength(j));
+            }
+        }
+    }
+
+    @Override
+    public void adjustMBR(ITreeIndexTupleReference[] tuples, MultiComparator cmp) {
+        for (int i = 0; i < tuples.length; i++) {
+            tuples[i].setFieldCount(cmp.getKeyFieldCount());
+            tuples[i].resetByTupleIndex(this, 0);
+        }
+
+        adjustMBRImpl(tuples, cmp);
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMInteriorFrameFactory.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMInteriorFrameFactory.java
new file mode 100644
index 0000000..9fd5a54
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMInteriorFrameFactory.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.frames;
+
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeInteriorFrame;
+
+public class RTreeNSMInteriorFrameFactory implements ITreeIndexFrameFactory {
+
+    private static final long serialVersionUID = 1L;
+    private ITreeIndexTupleWriterFactory tupleWriterFactory;
+    private int keyFieldCount;
+
+    public RTreeNSMInteriorFrameFactory(ITreeIndexTupleWriterFactory tupleWriterFactory, int keyFieldCount) {
+        this.tupleWriterFactory = tupleWriterFactory;
+        this.keyFieldCount = keyFieldCount;
+    }
+
+    @Override
+    public IRTreeInteriorFrame createFrame() {
+        return new RTreeNSMInteriorFrame(tupleWriterFactory.createTupleWriter(), keyFieldCount);
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMLeafFrame.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMLeafFrame.java
new file mode 100644
index 0000000..7ebe974
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMLeafFrame.java
@@ -0,0 +1,266 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.frames;
+
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.DoubleSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeLeafFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.EntriesOrder;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTreeSplitKey;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.UnorderedSlotManager;
+import edu.uci.ics.hyracks.storage.am.rtree.tuples.RTreeTypeAwareTupleWriter;
+
+public class RTreeNSMLeafFrame extends RTreeNSMFrame implements IRTreeLeafFrame {
+
+    public RTreeNSMLeafFrame(ITreeIndexTupleWriter tupleWriter, int keyFieldCount) {
+        super(tupleWriter, keyFieldCount);
+    }
+
+    @Override
+    public int findTupleIndex(ITupleReference tuple, MultiComparator cmp) {
+        frameTuple.setFieldCount(cmp.getFieldCount());
+        return slotManager.findTupleIndex(tuple, frameTuple, cmp, null, null);
+    }
+
+    @Override
+    public boolean intersect(ITupleReference tuple, int tupleIndex, MultiComparator cmp) {
+        frameTuple.setFieldCount(cmp.getFieldCount());
+        frameTuple.resetByTupleIndex(this, tupleIndex);
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < maxFieldPos; i++) {
+            int j = maxFieldPos + i;
+            int c = cmp.getComparators()[i].compare(tuple.getFieldData(i), tuple.getFieldStart(i),
+                    tuple.getFieldLength(i), frameTuple.getFieldData(j), frameTuple.getFieldStart(j),
+                    frameTuple.getFieldLength(j));
+            if (c > 0) {
+                return false;
+            }
+            c = cmp.getComparators()[i].compare(tuple.getFieldData(j), tuple.getFieldStart(j), tuple.getFieldLength(j),
+                    frameTuple.getFieldData(i), frameTuple.getFieldStart(i), frameTuple.getFieldLength(i));
+
+            if (c < 0) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public int split(ITreeIndexFrame rightFrame, ITupleReference tuple, MultiComparator cmp, ISplitKey splitKey)
+            throws Exception {
+
+        rightFrame.setPageTupleFieldCount(cmp.getFieldCount());
+        frameTuple.setFieldCount(cmp.getFieldCount());
+
+        RTreeSplitKey rTreeSplitKey = ((RTreeSplitKey) splitKey);
+        RTreeTypeAwareTupleWriter rTreeTupleWriterLeftFrame = ((RTreeTypeAwareTupleWriter) tupleWriter);
+        RTreeTypeAwareTupleWriter rTreeTupleWriterRightFrame = ((RTreeTypeAwareTupleWriter) rightFrame.getTupleWriter());
+
+        // calculations are based on the R*-tree paper
+        int m = (int) Math.floor((getTupleCount() + 1) * splitFactor);
+        int splitDistribution = getTupleCount() - (2 * m) + 2;
+
+        // to calculate the minimum margin in order to pick the split axis
+        double minMargin = Double.MAX_VALUE;
+        int splitAxis = 0, sortOrder = 0;
+
+        int maxFieldPos = cmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < maxFieldPos; i++) {
+            int j = maxFieldPos + i;
+            for (int k = 0; k < getTupleCount(); ++k) {
+
+                frameTuple.resetByTupleIndex(this, k);
+
+                double LowerKey = DoubleSerializerDeserializer.getDouble(frameTuple.getFieldData(i),
+                        frameTuple.getFieldStart(i));
+                double UpperKey = DoubleSerializerDeserializer.getDouble(frameTuple.getFieldData(j),
+                        frameTuple.getFieldStart(j));
+
+                tupleEntries1.add(k, LowerKey);
+                tupleEntries2.add(k, UpperKey);
+            }
+            double LowerKey = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(i), tuple.getFieldStart(i));
+            double UpperKey = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(j), tuple.getFieldStart(j));
+
+            tupleEntries1.add(-1, LowerKey);
+            tupleEntries2.add(-1, UpperKey);
+
+            tupleEntries1.sort(EntriesOrder.ASCENDING, getTupleCount() + 1);
+            tupleEntries2.sort(EntriesOrder.ASCENDING, getTupleCount() + 1);
+
+            double lowerMargin = 0.0, upperMargin = 0.0;
+            // generate distribution
+            for (int k = 1; k <= splitDistribution; ++k) {
+                int d = m - 1 + k;
+
+                generateDist(tuple, tupleEntries1, rec[0], 0, d);
+                generateDist(tuple, tupleEntries2, rec[1], 0, d);
+                generateDist(tuple, tupleEntries1, rec[2], d, getTupleCount() + 1);
+                generateDist(tuple, tupleEntries2, rec[3], d, getTupleCount() + 1);
+
+                // calculate the margin of the distributions
+                lowerMargin += rec[0].margin() + rec[2].margin();
+                upperMargin += rec[1].margin() + rec[3].margin();
+            }
+            double margin = Math.min(lowerMargin, upperMargin);
+
+            // store minimum margin as split axis
+            if (margin < minMargin) {
+                minMargin = margin;
+                splitAxis = i;
+                sortOrder = (lowerMargin < upperMargin) ? 0 : 2;
+            }
+
+            tupleEntries1.clear();
+            tupleEntries2.clear();
+        }
+
+        for (int i = 0; i < getTupleCount(); ++i) {
+            frameTuple.resetByTupleIndex(this, i);
+            double key = DoubleSerializerDeserializer.getDouble(frameTuple.getFieldData(splitAxis + sortOrder),
+                    frameTuple.getFieldStart(splitAxis + sortOrder));
+            tupleEntries1.add(i, key);
+        }
+        double key = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(splitAxis + sortOrder),
+                tuple.getFieldStart(splitAxis + sortOrder));
+        tupleEntries1.add(-1, key);
+        tupleEntries1.sort(EntriesOrder.ASCENDING, getTupleCount() + 1);
+
+        double minArea = Double.MAX_VALUE;
+        double minOverlap = Double.MAX_VALUE;
+        int splitPoint = 0;
+        for (int i = 1; i <= splitDistribution; ++i) {
+            int d = m - 1 + i;
+
+            generateDist(tuple, tupleEntries1, rec[0], 0, d);
+            generateDist(tuple, tupleEntries1, rec[2], d, getTupleCount() + 1);
+
+            double overlap = rec[0].overlappedArea(rec[2]);
+            if (overlap < minOverlap) {
+                splitPoint = d;
+                minOverlap = overlap;
+                minArea = rec[0].area() + rec[2].area();
+            } else if (overlap == minOverlap) {
+                double area = rec[0].area() + rec[2].area();
+                if (area < minArea) {
+                    splitPoint = d;
+                    minArea = area;
+                }
+            }
+        }
+        int startIndex, endIndex;
+        if (splitPoint < (getTupleCount() + 1) / 2) {
+            startIndex = 0;
+            endIndex = splitPoint;
+        } else {
+            startIndex = splitPoint;
+            endIndex = (getTupleCount() + 1);
+        }
+        boolean tupleInserted = false;
+        int totalBytes = 0, numOfDeletedTuples = 0;
+        for (int i = startIndex; i < endIndex; i++) {
+            if (tupleEntries1.get(i).getTupleIndex() != -1) {
+                frameTuple.resetByTupleIndex(this, tupleEntries1.get(i).getTupleIndex());
+                rightFrame.insert(frameTuple, cmp, -1);
+                ((UnorderedSlotManager) slotManager).modifySlot(
+                        slotManager.getSlotOff(tupleEntries1.get(i).getTupleIndex()), -1);
+                totalBytes += tupleWriter.bytesRequired(frameTuple);
+                numOfDeletedTuples++;
+            } else {
+                rightFrame.insert(tuple, cmp, -1);
+                tupleInserted = true;
+            }
+        }
+
+        ((UnorderedSlotManager) slotManager).deleteEmptySlots();
+
+        // maintain space information
+        buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) + totalBytes
+                + (slotManager.getSlotSize() * numOfDeletedTuples));
+
+        // compact both pages
+        rightFrame.compact(cmp);
+        compact(cmp);
+
+        if (!tupleInserted) {
+            insert(tuple, cmp, -1);
+        }
+
+        int tupleOff = slotManager.getTupleOff(slotManager.getSlotEndOff());
+        frameTuple.resetByTupleOffset(buf, tupleOff);
+        int splitKeySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
+
+        splitKey.initData(splitKeySize);
+        this.adjustMBR(tuples, cmp);
+        rTreeTupleWriterLeftFrame.writeTupleFields(tuples, 0, rTreeSplitKey.getLeftPageBuffer(), 0);
+        rTreeSplitKey.getLeftTuple().resetByTupleOffset(rTreeSplitKey.getLeftPageBuffer(), 0);
+
+        ((IRTreeFrame) rightFrame).adjustMBR(((RTreeNSMFrame) rightFrame).getTuples(), cmp);
+        rTreeTupleWriterRightFrame.writeTupleFields(((RTreeNSMFrame) rightFrame).getTuples(), 0,
+                rTreeSplitKey.getRightPageBuffer(), 0);
+        rTreeSplitKey.getRightTuple().resetByTupleOffset(rTreeSplitKey.getRightPageBuffer(), 0);
+
+        tupleEntries1.clear();
+        tupleEntries2.clear();
+        return 0;
+    }
+
+    @Override
+    public void insert(ITupleReference tuple, MultiComparator cmp, int tupleIndex) throws Exception {
+        frameTuple.setFieldCount(cmp.getFieldCount());
+        slotManager.insertSlot(-1, buf.getInt(freeSpaceOff));
+        int bytesWritten = tupleWriter.writeTuple(tuple, buf, buf.getInt(freeSpaceOff));
+
+        buf.putInt(tupleCountOff, buf.getInt(tupleCountOff) + 1);
+        buf.putInt(freeSpaceOff, buf.getInt(freeSpaceOff) + bytesWritten);
+        buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) - bytesWritten - slotManager.getSlotSize());
+    }
+
+    @Override
+    public void delete(int tupleIndex, MultiComparator cmp) throws Exception {
+        frameTuple.setFieldCount(cmp.getFieldCount());
+        int slotOff = slotManager.getSlotOff(tupleIndex);
+
+        int tupleOff = slotManager.getTupleOff(slotOff);
+        frameTuple.resetByTupleOffset(buf, tupleOff);
+        int tupleSize = tupleWriter.bytesRequired(frameTuple);
+
+        // perform deletion (we just do a memcpy to overwrite the slot)
+        int slotStartOff = slotManager.getSlotEndOff();
+        int length = slotOff - slotStartOff;
+        System.arraycopy(buf.array(), slotStartOff, buf.array(), slotStartOff + slotManager.getSlotSize(), length);
+
+        // maintain space information
+        buf.putInt(tupleCountOff, buf.getInt(tupleCountOff) - 1);
+        buf.putInt(totalFreeSpaceOff, buf.getInt(totalFreeSpaceOff) + tupleSize + slotManager.getSlotSize());
+    }
+
+    @Override
+    public void adjustMBR(ITreeIndexTupleReference[] tuples, MultiComparator cmp) {
+        for (int i = 0; i < tuples.length; i++) {
+            tuples[i].setFieldCount(cmp.getFieldCount());
+            tuples[i].resetByTupleIndex(this, 0);
+        }
+
+        adjustMBRImpl(tuples, cmp);
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMLeafFrameFactory.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMLeafFrameFactory.java
new file mode 100644
index 0000000..7da7f26
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/frames/RTreeNSMLeafFrameFactory.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.frames;
+
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeLeafFrame;
+
+public class RTreeNSMLeafFrameFactory implements ITreeIndexFrameFactory {
+
+    private static final long serialVersionUID = 1L;
+    private ITreeIndexTupleWriterFactory tupleWriterFactory;
+    private int keyFieldCount;
+
+    public RTreeNSMLeafFrameFactory(ITreeIndexTupleWriterFactory tupleWriterFactory, int keyFieldCount) {
+        this.tupleWriterFactory = tupleWriterFactory;
+        this.keyFieldCount = keyFieldCount;
+    }
+
+    @Override
+    public IRTreeLeafFrame createFrame() {
+        return new RTreeNSMLeafFrame(tupleWriterFactory.createTupleWriter(), keyFieldCount);
+    }
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOp.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/EntriesOrder.java
similarity index 83%
rename from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOp.java
rename to hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/EntriesOrder.java
index d698c8a..8dce1ac 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/impls/BTreeOp.java
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/EntriesOrder.java
@@ -13,8 +13,8 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.impls;
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
 
-public enum BTreeOp {
-    BTO_INSERT, BTO_DELETE, BTO_UPDATE, BTO_SEARCH
+public enum EntriesOrder {
+    ASCENDING, DESCENDING
 }
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/PathList.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/PathList.java
new file mode 100644
index 0000000..58bad69
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/PathList.java
@@ -0,0 +1,110 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IntArrayList;
+
+public class PathList {
+    private IntArrayList pageIds;
+    private IntArrayList pageLsns;
+    private IntArrayList pageIndexes;
+
+    public PathList(int initialCapacity, int growth) {
+        pageIds = new IntArrayList(initialCapacity, growth);
+        pageLsns = new IntArrayList(initialCapacity, growth);
+        pageIndexes = new IntArrayList(initialCapacity, growth);
+    }
+
+    public int size() {
+        return pageIds.size();
+    }
+
+    public int first() {
+        return pageIds.first();
+    }
+
+    public void add(int pageId, int pageLsn, int pageIndex) {
+        pageIds.add(pageId);
+        pageLsns.add(pageLsn);
+        pageIndexes.add(pageIndex);
+    }
+
+    public int getFirstPageId() {
+        return pageIds.getFirst();
+    }
+
+    public int getFirstPageLsn() {
+        return pageLsns.getFirst();
+    }
+
+    public int getFirstPageIndex() {
+        return pageIndexes.getFirst();
+    }
+
+    public int getLastPageId() {
+        return pageIds.getLast();
+    }
+
+    public int getLastPageLsn() {
+        return pageLsns.getLast();
+    }
+
+    public int getLastPageIndex() {
+        return pageIndexes.getLast();
+    }
+
+    public int getPageId(int i) {
+        return pageIds.get(i);
+    }
+
+    public int getPageLsn(int i) {
+        return pageLsns.get(i);
+    }
+
+    public int getPageIndex(int i) {
+        return pageIndexes.get(i);
+    }
+
+    public void setPageLsn(int i, int pageLsn) {
+        pageLsns.set(i, pageLsn);
+    }
+
+    public void moveFirst() {
+        pageIds.moveFirst();
+        pageLsns.moveFirst();
+        pageIndexes.moveFirst();
+    }
+
+    public void moveLast() {
+        pageIds.removeLast();
+        pageLsns.removeLast();
+        pageIndexes.removeLast();
+    }
+
+    public boolean isLast() {
+        return pageIds.isLast();
+    }
+
+    public void clear() {
+        pageIds.clear();
+        pageLsns.clear();
+        pageIndexes.clear();
+    }
+
+    public boolean isEmpty() {
+        return pageIds.isEmpty();
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTree.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTree.java
new file mode 100644
index 0000000..8976409
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTree.java
@@ -0,0 +1,937 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import java.util.ArrayList;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.locks.ReadWriteLock;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexBulkLoadContext;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.IndexType;
+import edu.uci.ics.hyracks.storage.am.common.frames.FrameOpSpaceStatus;
+import edu.uci.ics.hyracks.storage.am.common.impls.TreeDiskOrderScanCursor;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOpContext;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeInteriorFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeLeafFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreeNSMFrame;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
+
+public class RTree implements ITreeIndex {
+
+    private boolean created = false;
+    private boolean loaded = false;
+    private final int rootPage = 1; // the root page never changes
+
+    private final AtomicInteger globalNsn; // Global node sequence number
+    private int numOfPages = 1;
+    private final ReadWriteLock treeLatch;
+
+    private final IFreePageManager freePageManager;
+    private final IBufferCache bufferCache;
+    private int fileId;
+
+    private final SearchPredicate diskOrderScanPredicate;
+    private final ITreeIndexFrameFactory interiorFrameFactory;
+    private final ITreeIndexFrameFactory leafFrameFactory;
+    private final MultiComparator cmp;
+
+    public int rootSplits = 0;
+    public int[] splitsByLevel = new int[500];
+    public AtomicLong readLatchesAcquired = new AtomicLong();
+    public AtomicLong readLatchesReleased = new AtomicLong();
+    public AtomicLong writeLatchesAcquired = new AtomicLong();
+    public AtomicLong writeLatchesReleased = new AtomicLong();
+    public AtomicLong pins = new AtomicLong();
+    public AtomicLong unpins = new AtomicLong();
+    public byte currentLevel = 0;
+
+    public RTree(IBufferCache bufferCache, IFreePageManager freePageManager,
+            ITreeIndexFrameFactory interiorFrameFactory, ITreeIndexFrameFactory leafFrameFactory, MultiComparator cmp) {
+        this.bufferCache = bufferCache;
+        this.freePageManager = freePageManager;
+        this.interiorFrameFactory = interiorFrameFactory;
+        this.leafFrameFactory = leafFrameFactory;
+        this.cmp = cmp;
+        globalNsn = new AtomicInteger();
+        this.treeLatch = new ReentrantReadWriteLock(true);
+        this.diskOrderScanPredicate = new SearchPredicate(null, cmp);
+    }
+
+    public void incrementGlobalNsn() {
+        globalNsn.incrementAndGet();
+    }
+
+    public int getGlobalNsn() {
+        return globalNsn.get();
+    }
+
+    public void incrementReadLatchesAcquired() {
+        readLatchesAcquired.incrementAndGet();
+    }
+
+    public void incrementReadLatchesReleased() {
+        readLatchesReleased.incrementAndGet();
+    }
+
+    public void incrementWriteLatchesAcquired() {
+        writeLatchesAcquired.incrementAndGet();
+    }
+
+    public void incrementWriteLatchesReleased() {
+        writeLatchesReleased.incrementAndGet();
+    }
+
+    public void incrementPins() {
+        pins.incrementAndGet();
+    }
+
+    public void incrementUnpins() {
+        unpins.incrementAndGet();
+    }
+
+    public String printStats() {
+        StringBuilder strBuilder = new StringBuilder();
+        strBuilder.append("\n");
+        strBuilder.append("ROOTSPLITS: " + rootSplits + "\n");
+        strBuilder.append("SPLITS BY LEVEL\n");
+        for (int i = 0; i < currentLevel; i++) {
+            strBuilder.append(String.format("%3d ", i) + String.format("%8d ", splitsByLevel[i]) + "\n");
+        }
+        strBuilder.append(String.format("READ LATCHES:  %10d %10d\n", readLatchesAcquired.get(),
+                readLatchesReleased.get()));
+        strBuilder.append(String.format("WRITE LATCHES: %10d %10d\n", writeLatchesAcquired.get(),
+                writeLatchesReleased.get()));
+        strBuilder.append(String.format("PINS:          %10d %10d\n", pins.get(), unpins.get()));
+
+        strBuilder.append(String.format("Num of Pages:          %10d\n", numOfPages));
+
+        return strBuilder.toString();
+    }
+
+    public void printTree(IRTreeFrame leafFrame, IRTreeFrame interiorFrame, ISerializerDeserializer[] fields)
+            throws Exception {
+        printTree(rootPage, null, false, leafFrame, interiorFrame, fields);
+    }
+
+    public void printTree(int pageId, ICachedPage parent, boolean unpin, IRTreeFrame leafFrame,
+            IRTreeFrame interiorFrame, ISerializerDeserializer[] fields) throws Exception {
+
+        ICachedPage node = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+        incrementPins();
+        node.acquireReadLatch();
+        incrementReadLatchesAcquired();
+
+        try {
+            if (parent != null && unpin == true) {
+                parent.releaseReadLatch();
+                incrementReadLatchesReleased();
+                bufferCache.unpin(parent);
+                incrementUnpins();
+            }
+
+            interiorFrame.setPage(node);
+            int level = interiorFrame.getLevel();
+
+            System.out.format("%1d ", level);
+            System.out.format("%3d ", pageId);
+            for (int i = 0; i < currentLevel - level; i++)
+                System.out.format("    ");
+
+            String keyString;
+            if (interiorFrame.isLeaf()) {
+                leafFrame.setPage(node);
+                keyString = leafFrame.printKeys(cmp, fields);
+            } else {
+                keyString = interiorFrame.printKeys(cmp, fields);
+            }
+
+            System.out.format(keyString);
+            if (!interiorFrame.isLeaf()) {
+                ArrayList<Integer> children = ((RTreeNSMFrame) (interiorFrame)).getChildren(cmp);
+                for (int i = 0; i < children.size(); i++) {
+                    printTree(children.get(i), node, i == children.size() - 1, leafFrame, interiorFrame, fields);
+                }
+            } else {
+                node.releaseReadLatch();
+                incrementReadLatchesReleased();
+                bufferCache.unpin(node);
+                incrementUnpins();
+            }
+        } catch (Exception e) {
+            node.releaseReadLatch();
+            incrementReadLatchesReleased();
+            bufferCache.unpin(node);
+            incrementUnpins();
+            throw e;
+        }
+    }
+
+    @Override
+    public void create(int fileId, ITreeIndexFrame leafFrame, ITreeIndexMetaDataFrame metaFrame) throws Exception {
+        if (created)
+            return;
+
+        treeLatch.writeLock().lock();
+        try {
+            // check if another thread beat us to it
+            if (created)
+                return;
+
+            freePageManager.init(metaFrame, rootPage);
+
+            // initialize root page
+            ICachedPage rootNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, rootPage), true);
+            incrementPins();
+
+            rootNode.acquireWriteLatch();
+            incrementWriteLatchesAcquired();
+            try {
+                leafFrame.setPage(rootNode);
+                leafFrame.initBuffer((byte) 0);
+            } finally {
+                rootNode.releaseWriteLatch();
+                incrementWriteLatchesReleased();
+                bufferCache.unpin(rootNode);
+                incrementUnpins();
+            }
+            currentLevel = 0;
+
+            created = true;
+        } finally {
+            treeLatch.writeLock().unlock();
+        }
+    }
+
+    public void open(int fileId) {
+        this.fileId = fileId;
+    }
+
+    public void close() {
+        fileId = -1;
+    }
+
+    @Override
+    public RTreeOpContext createOpContext(IndexOp op, ITreeIndexFrame leafFrame, ITreeIndexFrame interiorFrame,
+            ITreeIndexMetaDataFrame metaFrame) {
+        return new RTreeOpContext(op, (IRTreeLeafFrame) leafFrame, (IRTreeInteriorFrame) interiorFrame, metaFrame, 8);
+    }
+
+    @Override
+    public void insert(ITupleReference tuple, IndexOpContext ictx) throws Exception {
+        RTreeOpContext ctx = (RTreeOpContext) ictx;
+        ctx.reset();
+        ctx.setTuple(tuple);
+        ctx.splitKey.reset();
+        ctx.splitKey.getLeftTuple().setFieldCount(cmp.getKeyFieldCount());
+        ctx.splitKey.getRightTuple().setFieldCount(cmp.getKeyFieldCount());
+        ctx.interiorFrame.setPageTupleFieldCount(cmp.getKeyFieldCount());
+        ctx.leafFrame.setPageTupleFieldCount(cmp.getFieldCount());
+
+        ICachedPage leafNode = findLeaf(ctx);
+
+        int pageId = ctx.pathList.getLastPageId();
+        ctx.pathList.moveLast();
+        insertTuple(leafNode, pageId, ctx.getTuple(), ctx, true);
+
+        while (true) {
+            if (ctx.splitKey.getLeftPageBuffer() != null) {
+                updateParentForInsert(ctx);
+            } else {
+                break;
+            }
+        }
+
+        leafNode.releaseWriteLatch();
+        incrementWriteLatchesReleased();
+        bufferCache.unpin(leafNode);
+        incrementUnpins();
+    }
+
+    public ICachedPage findLeaf(RTreeOpContext ctx) throws Exception {
+        int pageId = rootPage;
+        boolean writeLatched = false;
+        ICachedPage node = null;
+        boolean isLeaf = false;
+        int pageLsn = 0, parentLsn = 0;
+
+        while (true) {
+            if (!writeLatched) {
+                node = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+                incrementPins();
+                ctx.interiorFrame.setPage(node);
+                isLeaf = ctx.interiorFrame.isLeaf();
+                if (isLeaf) {
+                    node.acquireWriteLatch();
+                    incrementWriteLatchesAcquired();
+                    writeLatched = true;
+
+                    if (!ctx.interiorFrame.isLeaf()) {
+                        node.releaseWriteLatch();
+                        incrementWriteLatchesReleased();
+                        bufferCache.unpin(node);
+                        incrementUnpins();
+                        writeLatched = false;
+                        continue;
+                    }
+                } else {
+                    // Be optimistic and grab read latch first. We will swap it
+                    // to write latch if we need to enlarge the best child
+                    // tuple.
+                    node.acquireReadLatch();
+                    incrementReadLatchesAcquired();
+                }
+            }
+
+            if (pageId != rootPage && parentLsn < ctx.interiorFrame.getPageNsn()) {
+                // Concurrent split detected, go back to parent and re-choose
+                // the best child
+                if (writeLatched) {
+                    node.releaseWriteLatch();
+                    incrementWriteLatchesReleased();
+                    bufferCache.unpin(node);
+                    incrementUnpins();
+                    writeLatched = false;
+                } else {
+                    node.releaseReadLatch();
+                    incrementReadLatchesReleased();
+                    bufferCache.unpin(node);
+                    incrementUnpins();
+                }
+
+                pageId = ctx.pathList.getLastPageId();
+                if (pageId != rootPage) {
+                    parentLsn = ctx.pathList.getPageLsn(ctx.pathList.size() - 2);
+                }
+                ctx.pathList.moveLast();
+                continue;
+            }
+
+            pageLsn = ctx.interiorFrame.getPageLsn();
+            ctx.pathList.add(pageId, pageLsn, -1);
+
+            if (!isLeaf) {
+                // findBestChild must be called *before* getBestChildPageId
+                ctx.interiorFrame.findBestChild(ctx.getTuple(), cmp);
+                int childPageId = ctx.interiorFrame.getBestChildPageId(cmp);
+
+                if (!writeLatched) {
+                    node.releaseReadLatch();
+                    incrementReadLatchesReleased();
+                    // TODO: do we need to un-pin and pin again?
+                    bufferCache.unpin(node);
+                    incrementUnpins();
+
+                    node = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+                    incrementPins();
+                    node.acquireWriteLatch();
+                    incrementWriteLatchesAcquired();
+                    ctx.interiorFrame.setPage(node);
+                    writeLatched = true;
+
+                    if (ctx.interiorFrame.getPageLsn() != pageLsn) {
+                        // The page was changed while we unlocked it; thus,
+                        // retry (re-choose best child)
+
+                        ctx.pathList.moveLast();
+                        continue;
+                    }
+                }
+
+                // We don't need to reset the frameTuple because it is
+                // already pointing to the best child
+                ctx.interiorFrame.enlarge(ctx.getTuple(), cmp);
+
+                node.releaseWriteLatch();
+                incrementWriteLatchesReleased();
+                bufferCache.unpin(node);
+                incrementUnpins();
+                writeLatched = false;
+
+                pageId = childPageId;
+                parentLsn = pageLsn;
+            } else {
+                ctx.leafFrame.setPage(node);
+                return node;
+            }
+        }
+    }
+
+    private void insertTuple(ICachedPage node, int pageId, ITupleReference tuple, RTreeOpContext ctx, boolean isLeaf)
+            throws Exception {
+        FrameOpSpaceStatus spaceStatus;
+        if (!isLeaf) {
+            spaceStatus = ctx.interiorFrame.hasSpaceInsert(tuple, cmp);
+        } else {
+            spaceStatus = ctx.leafFrame.hasSpaceInsert(tuple, cmp);
+        }
+
+        switch (spaceStatus) {
+            case SUFFICIENT_CONTIGUOUS_SPACE: {
+                if (!isLeaf) {
+                    ctx.interiorFrame.insert(tuple, cmp, -1);
+                    incrementGlobalNsn();
+                    ctx.interiorFrame.setPageLsn(getGlobalNsn());
+                } else {
+                    ctx.leafFrame.insert(tuple, cmp, -1);
+                    incrementGlobalNsn();
+                    ctx.leafFrame.setPageLsn(getGlobalNsn());
+                }
+                ctx.splitKey.reset();
+                break;
+            }
+
+            case SUFFICIENT_SPACE: {
+                if (!isLeaf) {
+                    ctx.interiorFrame.compact(cmp);
+                    ctx.interiorFrame.insert(tuple, cmp, -1);
+                    incrementGlobalNsn();
+                    ctx.interiorFrame.setPageLsn(getGlobalNsn());
+                } else {
+                    ctx.leafFrame.compact(cmp);
+                    ctx.leafFrame.insert(tuple, cmp, -1);
+                    incrementGlobalNsn();
+                    ctx.leafFrame.setPageLsn(getGlobalNsn());
+                }
+                ctx.splitKey.reset();
+                break;
+            }
+
+            case INSUFFICIENT_SPACE: {
+                int rightPageId = freePageManager.getFreePage(ctx.metaFrame);
+                ICachedPage rightNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, rightPageId), true);
+                incrementPins();
+                rightNode.acquireWriteLatch();
+                incrementWriteLatchesAcquired();
+
+                try {
+                    IRTreeFrame rightFrame;
+                    int ret;
+                    numOfPages++; // debug
+                    if (!isLeaf) {
+                        splitsByLevel[ctx.interiorFrame.getLevel()]++; // debug
+                        rightFrame = (IRTreeFrame) interiorFrameFactory.createFrame();
+                        rightFrame.setPage(rightNode);
+                        rightFrame.initBuffer((byte) ctx.interiorFrame.getLevel());
+                        rightFrame.setPageTupleFieldCount(cmp.getKeyFieldCount());
+                        ret = ctx.interiorFrame.split(rightFrame, tuple, cmp, ctx.splitKey);
+                        ctx.interiorFrame.setRightPage(rightPageId);
+                        rightFrame.setPageNsn(ctx.interiorFrame.getPageNsn());
+                        incrementGlobalNsn();
+                        int newNsn = getGlobalNsn();
+                        rightFrame.setPageLsn(newNsn);
+                        ctx.interiorFrame.setPageNsn(newNsn);
+                        ctx.interiorFrame.setPageLsn(newNsn);
+                    } else {
+                        splitsByLevel[0]++; // debug
+                        rightFrame = (IRTreeFrame) leafFrameFactory.createFrame();
+                        rightFrame.setPage(rightNode);
+                        rightFrame.initBuffer((byte) 0);
+                        rightFrame.setPageTupleFieldCount(cmp.getFieldCount());
+                        ret = ctx.leafFrame.split(rightFrame, tuple, cmp, ctx.splitKey);
+                        ctx.leafFrame.setRightPage(rightPageId);
+                        rightFrame.setPageNsn(ctx.leafFrame.getPageNsn());
+                        incrementGlobalNsn();
+                        int newNsn = getGlobalNsn();
+                        rightFrame.setPageLsn(newNsn);
+                        ctx.leafFrame.setPageNsn(newNsn);
+                        ctx.leafFrame.setPageLsn(newNsn);
+                    }
+                    if (ret != 0) {
+                        ctx.splitKey.reset();
+                    } else {
+                        ctx.splitKey.setPages(pageId, rightPageId);
+                    }
+                    if (pageId == rootPage) {
+                        rootSplits++; // debug
+                        splitsByLevel[currentLevel]++;
+                        currentLevel++;
+
+                        int newLeftId = freePageManager.getFreePage(ctx.metaFrame);
+                        ICachedPage newLeftNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, newLeftId),
+                                true);
+                        incrementPins();
+                        newLeftNode.acquireWriteLatch();
+                        incrementWriteLatchesAcquired();
+                        try {
+                            // copy left child to new left child
+                            System.arraycopy(node.getBuffer().array(), 0, newLeftNode.getBuffer().array(), 0,
+                                    newLeftNode.getBuffer().capacity());
+
+                            // initialize new root (leftNode becomes new root)
+                            ctx.interiorFrame.setPage(node);
+                            ctx.interiorFrame.initBuffer((byte) (ctx.interiorFrame.getLevel() + 1));
+
+                            ctx.splitKey.setLeftPage(newLeftId);
+
+                            ctx.interiorFrame.insert(ctx.splitKey.getLeftTuple(), cmp, -1);
+                            ctx.interiorFrame.insert(ctx.splitKey.getRightTuple(), cmp, -1);
+
+                            incrementGlobalNsn();
+                            int newNsn = getGlobalNsn();
+                            ctx.interiorFrame.setPageLsn(newNsn);
+                            ctx.interiorFrame.setPageNsn(newNsn);
+                        } finally {
+                            newLeftNode.releaseWriteLatch();
+                            incrementWriteLatchesReleased();
+                            bufferCache.unpin(newLeftNode);
+                            incrementUnpins();
+                        }
+
+                        ctx.splitKey.reset();
+                    }
+                } finally {
+                    rightNode.releaseWriteLatch();
+                    incrementWriteLatchesReleased();
+                    bufferCache.unpin(rightNode);
+                    incrementUnpins();
+                }
+                break;
+            }
+        }
+    }
+
+    public void updateParentForInsert(RTreeOpContext ctx) throws Exception {
+        int parentId = ctx.pathList.getLastPageId();
+        ICachedPage parentNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, parentId), false);
+        incrementPins();
+        parentNode.acquireWriteLatch();
+        incrementWriteLatchesAcquired();
+        ctx.interiorFrame.setPage(parentNode);
+        boolean foundParent = true;
+
+        if (ctx.interiorFrame.getPageLsn() != ctx.pathList.getLastPageLsn()) {
+            foundParent = false;
+            while (true) {
+                if (ctx.interiorFrame.findTupleByPointer(ctx.splitKey.getLeftTuple(), cmp) != -1) {
+                    // found the parent
+                    foundParent = true;
+                    break;
+                }
+                int rightPage = ctx.interiorFrame.getRightPage();
+                parentNode.releaseWriteLatch();
+                incrementWriteLatchesReleased();
+                bufferCache.unpin(parentNode);
+                incrementUnpins();
+
+                if (rightPage == -1) {
+                    break;
+                }
+
+                parentId = rightPage;
+                parentNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, parentId), false);
+                incrementPins();
+                parentNode.acquireWriteLatch();
+                incrementWriteLatchesAcquired();
+                ctx.interiorFrame.setPage(parentNode);
+            }
+        }
+        if (foundParent) {
+            ctx.interiorFrame.adjustKey(ctx.splitKey.getLeftTuple(), -1, cmp);
+            insertTuple(parentNode, parentId, ctx.splitKey.getRightTuple(), ctx, ctx.interiorFrame.isLeaf());
+            ctx.pathList.moveLast();
+
+            parentNode.releaseWriteLatch();
+            incrementWriteLatchesReleased();
+            bufferCache.unpin(parentNode);
+            incrementUnpins();
+            return;
+        }
+
+        // very rare situation when the there is a root split, do an exhaustive
+        // breadth-first traversal looking for the parent tuple
+
+        ctx.pathList.clear();
+        ctx.traverseList.clear();
+        findPath(ctx);
+        updateParentForInsert(ctx);
+    }
+
+    public void findPath(RTreeOpContext ctx) throws Exception {
+        int pageId = rootPage;
+        int parentIndex = -1;
+        int parentLsn = 0;
+        int pageLsn, pageIndex;
+        ctx.traverseList.add(pageId, -1, parentIndex);
+        while (!ctx.traverseList.isLast()) {
+            pageId = ctx.traverseList.getFirstPageId();
+            parentIndex = ctx.traverseList.getFirstPageIndex();
+
+            ICachedPage node = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+            incrementPins();
+            node.acquireReadLatch();
+            incrementReadLatchesAcquired();
+            ctx.interiorFrame.setPage(node);
+            pageLsn = ctx.interiorFrame.getPageLsn();
+            pageIndex = ctx.traverseList.first();
+            ctx.traverseList.setPageLsn(pageIndex, pageLsn);
+
+            ctx.traverseList.moveFirst();
+
+            if (pageId != rootPage && parentLsn < ctx.interiorFrame.getPageNsn()) {
+                int rightPage = ctx.interiorFrame.getRightPage();
+                if (rightPage != -1) {
+                    ctx.traverseList.add(rightPage, -1, parentIndex);
+                }
+            }
+            parentLsn = pageLsn;
+
+            if (ctx.interiorFrame.findTupleByPointer(ctx.splitKey.getLeftTuple(), ctx.traverseList, pageIndex, cmp) != -1) {
+                fillPath(ctx, pageIndex);
+
+                node.releaseReadLatch();
+                incrementReadLatchesReleased();
+                bufferCache.unpin(node);
+                incrementUnpins();
+                return;
+            }
+            node.releaseReadLatch();
+            incrementReadLatchesReleased();
+            bufferCache.unpin(node);
+            incrementUnpins();
+        }
+    }
+
+    public void fillPath(RTreeOpContext ctx, int pageIndex) throws Exception {
+        if (pageIndex != -1) {
+            fillPath(ctx, ctx.traverseList.getPageIndex(pageIndex));
+            ctx.pathList.add(ctx.traverseList.getPageId(pageIndex), ctx.traverseList.getPageLsn(pageIndex), -1);
+        }
+    }
+
+    @Override
+    public void delete(ITupleReference tuple, IndexOpContext ictx) throws Exception {
+        RTreeOpContext ctx = (RTreeOpContext) ictx;
+        ctx.reset();
+        ctx.setTuple(tuple);
+        ctx.splitKey.reset();
+        ctx.splitKey.getLeftTuple().setFieldCount(cmp.getKeyFieldCount());
+        ctx.interiorFrame.setPageTupleFieldCount(cmp.getKeyFieldCount());
+        ctx.leafFrame.setPageTupleFieldCount(cmp.getFieldCount());
+
+        int tupleIndex = findTupleToDelete(ctx);
+
+        if (tupleIndex != -1) {
+            int pageId = ctx.pathList.getLastPageId();
+            ctx.pathList.moveLast();
+            deleteTuple(pageId, tupleIndex, ctx);
+
+            while (true) {
+                if (ctx.splitKey.getLeftPageBuffer() != null) {
+                    updateParentForDelete(ctx);
+                } else {
+                    break;
+                }
+            }
+
+            ctx.leafFrame.getPage().releaseWriteLatch();
+            incrementWriteLatchesReleased();
+            bufferCache.unpin(ctx.leafFrame.getPage());
+            incrementUnpins();
+        }
+    }
+
+    public void updateParentForDelete(RTreeOpContext ctx) throws Exception {
+        int parentId = ctx.pathList.getLastPageId();
+        ICachedPage parentNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, parentId), false);
+        incrementPins();
+        parentNode.acquireWriteLatch();
+        incrementWriteLatchesAcquired();
+        ctx.interiorFrame.setPage(parentNode);
+        boolean foundParent = true;
+        int tupleIndex = -1;
+
+        if (ctx.interiorFrame.getPageLsn() != ctx.pathList.getLastPageLsn()) {
+            foundParent = false;
+            while (true) {
+                tupleIndex = ctx.interiorFrame.findTupleByPointer(ctx.splitKey.getLeftTuple(), cmp);
+                if (tupleIndex != -1) {
+                    // found the parent
+                    foundParent = true;
+                    break;
+                }
+                int rightPage = ctx.interiorFrame.getRightPage();
+                parentNode.releaseWriteLatch();
+                incrementWriteLatchesReleased();
+                bufferCache.unpin(parentNode);
+                incrementUnpins();
+
+                if (rightPage == -1) {
+                    break;
+                }
+
+                parentId = rightPage;
+                parentNode = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, parentId), false);
+                incrementPins();
+                parentNode.acquireWriteLatch();
+                incrementWriteLatchesAcquired();
+                ctx.interiorFrame.setPage(parentNode);
+            }
+        }
+        if (foundParent) {
+            if (tupleIndex == -1) {
+                tupleIndex = ctx.interiorFrame.findTupleByPointer(ctx.splitKey.getLeftTuple(), cmp);
+            }
+            boolean recomputeMBR = ctx.interiorFrame.recomputeMBR(ctx.splitKey.getLeftTuple(), tupleIndex, cmp);
+
+            if (recomputeMBR) {
+                ctx.interiorFrame.adjustKey(ctx.splitKey.getLeftTuple(), tupleIndex, cmp);
+                ctx.pathList.moveLast();
+
+                incrementGlobalNsn();
+                ctx.interiorFrame.setPageLsn(getGlobalNsn());
+
+                ctx.splitKey.reset();
+                if (!ctx.pathList.isEmpty()) {
+                    ctx.interiorFrame.computeMBR(ctx.splitKey, cmp);
+                    ctx.splitKey.setLeftPage(parentId);
+                }
+            } else {
+                ctx.pathList.moveLast();
+                ctx.splitKey.reset();
+            }
+
+            parentNode.releaseWriteLatch();
+            incrementWriteLatchesReleased();
+            bufferCache.unpin(parentNode);
+            incrementUnpins();
+            return;
+        }
+
+        // very rare situation when the there is a root split, do an exhaustive
+        // breadth-first traversal looking for the parent tuple
+
+        ctx.pathList.clear();
+        ctx.traverseList.clear();
+        findPath(ctx);
+        updateParentForDelete(ctx);
+    }
+
+    public int findTupleToDelete(RTreeOpContext ctx) throws Exception {
+
+        ctx.traverseList.add(rootPage, -1, -1);
+        ctx.pathList.add(rootPage, -1, ctx.traverseList.size() - 1);
+
+        while (!ctx.pathList.isEmpty()) {
+            int pageId = ctx.pathList.getLastPageId();
+            int parentLsn = ctx.pathList.getLastPageLsn();
+            int pageIndex = ctx.pathList.getLastPageIndex();
+            ctx.pathList.moveLast();
+            ICachedPage node = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+            incrementPins();
+            node.acquireReadLatch();
+            incrementReadLatchesAcquired();
+            ctx.interiorFrame.setPage(node);
+            boolean isLeaf = ctx.interiorFrame.isLeaf();
+            int pageLsn = ctx.interiorFrame.getPageLsn();
+            int parentIndex = ctx.traverseList.getPageIndex(pageIndex);
+            ctx.traverseList.setPageLsn(pageIndex, pageLsn);
+
+            if (pageId != rootPage && parentLsn < ctx.interiorFrame.getPageNsn()) {
+                // Concurrent split detected, we need to visit the right page
+                int rightPage = ctx.interiorFrame.getRightPage();
+                if (rightPage != -1) {
+                    ctx.traverseList.add(rightPage, -1, parentIndex);
+                    ctx.pathList.add(rightPage, parentLsn, ctx.traverseList.size() - 1);
+                }
+            }
+
+            if (!isLeaf) {
+                for (int i = 0; i < ctx.interiorFrame.getTupleCount(); i++) {
+                    int childPageId = ctx.interiorFrame.getChildPageIdIfIntersect(ctx.tuple, i, cmp);
+                    if (childPageId != -1) {
+                        ctx.traverseList.add(childPageId, -1, pageIndex);
+                        ctx.pathList.add(childPageId, pageLsn, ctx.traverseList.size() - 1);
+                    }
+                }
+            } else {
+                ctx.leafFrame.setPage(node);
+                int tupleIndex = ctx.leafFrame.findTupleIndex(ctx.tuple, cmp);
+                if (tupleIndex != -1) {
+
+                    node.releaseReadLatch();
+                    incrementReadLatchesReleased();
+                    bufferCache.unpin(node);
+                    incrementUnpins();
+
+                    node = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+                    incrementPins();
+                    node.acquireWriteLatch();
+                    incrementWriteLatchesAcquired();
+                    ctx.leafFrame.setPage(node);
+
+                    if (ctx.leafFrame.getPageLsn() != pageLsn) {
+                        // The page was changed while we unlocked it
+
+                        tupleIndex = ctx.leafFrame.findTupleIndex(ctx.tuple, cmp);
+                        if (tupleIndex == -1) {
+                            ctx.traverseList.add(pageId, -1, parentIndex);
+                            ctx.pathList.add(pageId, parentLsn, ctx.traverseList.size() - 1);
+
+                            node.releaseWriteLatch();
+                            incrementWriteLatchesReleased();
+                            bufferCache.unpin(node);
+                            incrementUnpins();
+                            continue;
+                        } else {
+                            ctx.pathList.clear();
+                            fillPath(ctx, pageIndex);
+                            return tupleIndex;
+                        }
+                    } else {
+                        ctx.pathList.clear();
+                        fillPath(ctx, pageIndex);
+                        return tupleIndex;
+                    }
+                }
+            }
+            node.releaseReadLatch();
+            incrementReadLatchesReleased();
+            bufferCache.unpin(node);
+            incrementUnpins();
+        }
+        return -1;
+    }
+
+    public void deleteTuple(int pageId, int tupleIndex, RTreeOpContext ctx) throws Exception {
+        ctx.leafFrame.delete(tupleIndex, cmp);
+        incrementGlobalNsn();
+        ctx.leafFrame.setPageLsn(getGlobalNsn());
+
+        // if the page is empty, just leave it there for future inserts
+        if (pageId != rootPage && ctx.leafFrame.getTupleCount() > 0) {
+            ctx.leafFrame.computeMBR(ctx.splitKey, cmp);
+            ctx.splitKey.setLeftPage(pageId);
+        }
+    }
+
+    public void search(ITreeIndexCursor cursor, SearchPredicate pred, RTreeOpContext ctx) throws Exception {
+        ctx.reset();
+        ctx.cursor = cursor;
+
+        cursor.setBufferCache(bufferCache);
+        cursor.setFileId(fileId);
+        ctx.cursorInitialState.setRootPage(rootPage);
+        ctx.cursor.open(ctx.cursorInitialState, pred);
+    }
+
+    public ITreeIndexFrameFactory getInteriorFrameFactory() {
+        return interiorFrameFactory;
+    }
+
+    public ITreeIndexFrameFactory getLeafFrameFactory() {
+        return leafFrameFactory;
+    }
+
+    public MultiComparator getCmp() {
+        return cmp;
+    }
+
+    public IFreePageManager getFreePageManager() {
+        return freePageManager;
+    }
+
+    @Override
+    public void update(ITupleReference tuple, IndexOpContext ictx) throws Exception {
+        throw new Exception("RTree Update not implemented.");
+    }
+
+    public final class BulkLoadContext implements IIndexBulkLoadContext {
+
+        public RTreeOpContext insertOpCtx;
+
+        public BulkLoadContext(float fillFactor, IRTreeFrame leafFrame, IRTreeFrame interiorFrame,
+                ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException {
+
+            insertOpCtx = createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
+        }
+    }
+
+    @Override
+    public IIndexBulkLoadContext beginBulkLoad(float fillFactor, ITreeIndexFrame leafFrame,
+            ITreeIndexFrame interiorFrame, ITreeIndexMetaDataFrame metaFrame) throws HyracksDataException {
+        if (loaded)
+            throw new HyracksDataException("Trying to bulk-load RTree but has RTree already been loaded.");
+
+        BulkLoadContext ctx = new BulkLoadContext(fillFactor, (IRTreeFrame) leafFrame, (IRTreeFrame) interiorFrame,
+                metaFrame);
+        return ctx;
+    }
+
+    @Override
+    public void bulkLoadAddTuple(IIndexBulkLoadContext ictx, ITupleReference tuple) throws HyracksDataException {
+        try {
+            insert(tuple, ((BulkLoadContext) ictx).insertOpCtx);
+        } catch (Exception e) {
+            throw new HyracksDataException("BulkLoad Error");
+        }
+    }
+
+    @Override
+    public void endBulkLoad(IIndexBulkLoadContext ictx) throws HyracksDataException {
+        loaded = true;
+    }
+
+    @Override
+    public void diskOrderScan(ITreeIndexCursor icursor, ITreeIndexFrame leafFrame, ITreeIndexMetaDataFrame metaFrame,
+            IndexOpContext ictx) throws HyracksDataException {
+        TreeDiskOrderScanCursor cursor = (TreeDiskOrderScanCursor) icursor;
+        RTreeOpContext ctx = (RTreeOpContext) ictx;
+        ctx.reset();
+
+        int currentPageId = rootPage + 1;
+        int maxPageId = freePageManager.getMaxPage(metaFrame);
+
+        ICachedPage page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, currentPageId), false);
+        page.acquireReadLatch();
+        cursor.setBufferCache(bufferCache);
+        cursor.setFileId(fileId);
+        cursor.setCurrentPageId(currentPageId);
+        cursor.setMaxPageId(maxPageId);
+        ctx.cursorInitialState.setPage(page);
+        cursor.open(ctx.cursorInitialState, diskOrderScanPredicate);
+    }
+
+    @Override
+    public int getRootPageId() {
+        return rootPage;
+    }
+
+    @Override
+    public int getFieldCount() {
+        return cmp.getFieldCount();
+    }
+
+    @Override
+    public IndexType getIndexType() {
+        return IndexType.RTREE;
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeCursorInitialState.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeCursorInitialState.java
new file mode 100644
index 0000000..8b94a04
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeCursorInitialState.java
@@ -0,0 +1,51 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import edu.uci.ics.hyracks.storage.am.common.api.ICursorInitialState;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+
+public class RTreeCursorInitialState implements ICursorInitialState {
+
+    private PathList pathList;
+    private int rootPage;
+    private ICachedPage page; // for disk order scan
+
+    public RTreeCursorInitialState(PathList pathList, int rootPage) {
+        this.pathList = pathList;
+        this.rootPage = rootPage;
+    }
+
+    public PathList getPathList() {
+        return pathList;
+    }
+
+    public int getRootPage() {
+        return rootPage;
+    }
+
+    public void setRootPage(int rootPage) {
+        this.rootPage = rootPage;
+    }
+
+    public ICachedPage getPage() {
+        return page;
+    }
+
+    public void setPage(ICachedPage page) {
+        this.page = page;
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeOpContext.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeOpContext.java
new file mode 100644
index 0000000..ea8af28
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeOpContext.java
@@ -0,0 +1,74 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOpContext;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeInteriorFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeLeafFrame;
+
+public final class RTreeOpContext implements IndexOpContext {
+    public final IndexOp op;
+    public final IRTreeInteriorFrame interiorFrame;
+    public final IRTreeLeafFrame leafFrame;
+    public ITreeIndexCursor cursor;
+    public RTreeCursorInitialState cursorInitialState;
+    public final ITreeIndexMetaDataFrame metaFrame;
+    public final RTreeSplitKey splitKey;
+    public ITupleReference tuple;
+    public final PathList pathList; // used to record the pageIds and pageLsns
+                                    // of the visited pages
+    public final PathList traverseList; // used for traversing the tree
+    private static final int initTraverseListSize = 100;
+
+    public RTreeOpContext(IndexOp op, IRTreeLeafFrame leafFrame, IRTreeInteriorFrame interiorFrame,
+            ITreeIndexMetaDataFrame metaFrame, int treeHeightHint) {
+        this.op = op;
+        this.interiorFrame = interiorFrame;
+        this.leafFrame = leafFrame;
+        this.metaFrame = metaFrame;
+        pathList = new PathList(treeHeightHint, treeHeightHint);
+        if (op != IndexOp.SEARCH && op != IndexOp.DISKORDERSCAN) {
+            splitKey = new RTreeSplitKey(interiorFrame.getTupleWriter().createTupleReference(), interiorFrame
+                    .getTupleWriter().createTupleReference());
+            traverseList = new PathList(initTraverseListSize, initTraverseListSize);
+        } else {
+            splitKey = null;
+            traverseList = null;
+            cursorInitialState = new RTreeCursorInitialState(pathList, 1);
+        }
+    }
+
+    public ITupleReference getTuple() {
+        return tuple;
+    }
+
+    public void setTuple(ITupleReference tuple) {
+        this.tuple = tuple;
+    }
+
+    public void reset() {
+        if (pathList != null) {
+            pathList.clear();
+        }
+        if (traverseList != null) {
+            traverseList.clear();
+        }
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeSearchCursor.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeSearchCursor.java
new file mode 100644
index 0000000..86a7bfd
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeSearchCursor.java
@@ -0,0 +1,201 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ICursorInitialState;
+import edu.uci.ics.hyracks.storage.am.common.api.ISearchPredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeInteriorFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeLeafFrame;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
+
+public class RTreeSearchCursor implements ITreeIndexCursor {
+
+    private int fileId = -1;
+    private ICachedPage page = null;
+    private IRTreeInteriorFrame interiorFrame = null;
+    private IRTreeLeafFrame leafFrame = null;
+    private IBufferCache bufferCache = null;
+
+    private SearchPredicate pred;
+    private PathList pathList;
+    private int rootPage;
+    ITupleReference searchKey;
+
+    private int tupleIndex = 0;
+    private int tupleIndexInc = 0;
+
+    private MultiComparator cmp;
+
+    private ITreeIndexTupleReference frameTuple;
+    private boolean readLatched = false;
+
+    private int pin = 0;
+    private int unpin = 0;
+
+    public RTreeSearchCursor(IRTreeInteriorFrame interiorFrame, IRTreeLeafFrame leafFrame) {
+        this.interiorFrame = interiorFrame;
+        this.leafFrame = leafFrame;
+        this.frameTuple = leafFrame.createTupleReference();
+    }
+
+    @Override
+    public void close() throws Exception {
+        if (readLatched) {
+            page.releaseReadLatch();
+            bufferCache.unpin(page);
+            readLatched = false;
+        }
+        tupleIndex = 0;
+        tupleIndexInc = 0;
+        page = null;
+        pathList = null;
+    }
+
+    public ITupleReference getTuple() {
+        return frameTuple;
+    }
+
+    @Override
+    public ICachedPage getPage() {
+        return page;
+    }
+
+    public boolean fetchNextLeafPage() throws HyracksDataException {
+        if (readLatched) {
+            page.releaseReadLatch();
+            bufferCache.unpin(page);
+            unpin++;
+            readLatched = false;
+        }
+        while (!pathList.isEmpty()) {
+            int pageId = pathList.getLastPageId();
+            int parentLsn = pathList.getLastPageLsn();
+            pathList.moveLast();
+            ICachedPage node = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, pageId), false);
+            pin++;
+            node.acquireReadLatch();
+            readLatched = true;
+            interiorFrame.setPage(node);
+            boolean isLeaf = interiorFrame.isLeaf();
+            int pageLsn = interiorFrame.getPageLsn();
+
+            if (pageId != rootPage && parentLsn < interiorFrame.getPageNsn()) {
+                // Concurrent split detected, we need to visit the right page
+                int rightPage = interiorFrame.getRightPage();
+                if (rightPage != -1) {
+                    pathList.add(rightPage, parentLsn, -1);
+                }
+            }
+
+            if (!isLeaf) {
+                for (int i = 0; i < interiorFrame.getTupleCount(); i++) {
+                    int childPageId = interiorFrame.getChildPageIdIfIntersect(searchKey, i, cmp);
+                    if (childPageId != -1) {
+                        pathList.add(childPageId, pageLsn, -1);
+                    }
+                }
+            } else {
+                page = node;
+                leafFrame.setPage(page);
+                tupleIndex = 0;
+                return true;
+            }
+            node.releaseReadLatch();
+            readLatched = false;
+            bufferCache.unpin(node);
+            unpin++;
+        }
+        return false;
+    }
+
+    @Override
+    public boolean hasNext() throws Exception {
+        if (page == null) {
+            return false;
+        }
+
+        if (tupleIndex == leafFrame.getTupleCount()) {
+            if (!fetchNextLeafPage()) {
+                return false;
+            }
+        }
+
+        do {
+            for (int i = tupleIndex; i < leafFrame.getTupleCount(); i++) {
+                if (leafFrame.intersect(searchKey, i, cmp)) {
+                    frameTuple.resetByTupleIndex(leafFrame, i);
+                    tupleIndexInc = i + 1;
+                    return true;
+                }
+            }
+        } while (fetchNextLeafPage());
+        return false;
+    }
+
+    @Override
+    public void next() throws Exception {
+        tupleIndex = tupleIndexInc;
+    }
+
+    @Override
+    public void open(ICursorInitialState initialState, ISearchPredicate searchPred) throws Exception {
+        // in case open is called multiple times without closing
+        if (this.page != null) {
+            this.page.releaseReadLatch();
+            readLatched = false;
+            bufferCache.unpin(this.page);
+            pathList.clear();
+        }
+
+        pathList = ((RTreeCursorInitialState) initialState).getPathList();
+        rootPage = ((RTreeCursorInitialState) initialState).getRootPage();
+
+        pred = (SearchPredicate) searchPred;
+        cmp = pred.getLowKeyComparator();
+        searchKey = pred.getSearchKey();
+
+        pathList.add(this.rootPage, -1, -1);
+        frameTuple.setFieldCount(cmp.getFieldCount());
+        tupleIndex = 0;
+        fetchNextLeafPage();
+    }
+
+    @Override
+    public void reset() {
+        try {
+            close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+    @Override
+    public void setBufferCache(IBufferCache bufferCache) {
+        this.bufferCache = bufferCache;
+    }
+
+    @Override
+    public void setFileId(int fileId) {
+        this.fileId = fileId;
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeSplitKey.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeSplitKey.java
new file mode 100644
index 0000000..f220ea3
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/RTreeSplitKey.java
@@ -0,0 +1,152 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.storage.am.common.api.ISplitKey;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+
+public class RTreeSplitKey implements ISplitKey {
+    public byte[] leftPageData = null;
+    public ByteBuffer leftPageBuf = null;
+    public ITreeIndexTupleReference leftTuple;
+
+    public byte[] rightPageData = null;
+    public ByteBuffer rightPageBuf = null;
+    public ITreeIndexTupleReference rightTuple;
+
+    public int keySize = 0;
+
+    public RTreeSplitKey(ITreeIndexTupleReference leftTuple, ITreeIndexTupleReference rightTuple) {
+        this.leftTuple = leftTuple;
+        this.rightTuple = rightTuple;
+    }
+
+    public void initData(int keySize) {
+        // try to reuse existing memory from a lower-level split if possible
+        this.keySize = keySize;
+        if (leftPageData != null) {
+            if (leftPageData.length < keySize + 4) {
+                leftPageData = new byte[keySize + 4]; // add 4 for the page
+                leftPageBuf = ByteBuffer.wrap(leftPageData);
+            }
+        } else {
+            leftPageData = new byte[keySize + 4]; // add 4 for the page
+            leftPageBuf = ByteBuffer.wrap(leftPageData);
+        }
+        if (rightPageData != null) {
+            if (rightPageData.length < keySize + 4) {
+                rightPageData = new byte[keySize + 4]; // add 4 for the page
+                rightPageBuf = ByteBuffer.wrap(rightPageData);
+            }
+        } else {
+            rightPageData = new byte[keySize + 4]; // add 4 for the page
+            rightPageBuf = ByteBuffer.wrap(rightPageData);
+        }
+
+        leftTuple.resetByTupleOffset(leftPageBuf, 0);
+        rightTuple.resetByTupleOffset(rightPageBuf, 0);
+    }
+
+    public void resetLeftPage() {
+        leftPageData = null;
+        leftPageBuf = null;
+    }
+
+    public void resetRightPage() {
+        rightPageData = null;
+        rightPageBuf = null;
+    }
+
+    public ByteBuffer getLeftPageBuffer() {
+        return leftPageBuf;
+    }
+
+    public ByteBuffer getRightPageBuffer() {
+        return rightPageBuf;
+    }
+
+    public ITreeIndexTupleReference getLeftTuple() {
+        return leftTuple;
+    }
+
+    public ITreeIndexTupleReference getRightTuple() {
+        return rightTuple;
+    }
+
+    public int getLeftPage() {
+        return leftPageBuf.getInt(keySize);
+    }
+
+    public int getRightPage() {
+        return rightPageBuf.getInt(keySize);
+    }
+
+    public void setLeftPage(int page) {
+        leftPageBuf.putInt(keySize, page);
+    }
+
+    public void setRightPage(int page) {
+        rightPageBuf.putInt(keySize, page);
+    }
+
+    public ISplitKey duplicate(ITreeIndexTupleReference copyLeftTuple, ITreeIndexTupleReference copyRightTuple) {
+        RTreeSplitKey copy = new RTreeSplitKey(copyLeftTuple, copyRightTuple);
+        copy.leftPageData = leftPageData.clone();
+        copy.leftPageBuf = ByteBuffer.wrap(copy.leftPageData);
+        copy.leftTuple.setFieldCount(leftTuple.getFieldCount());
+        copy.leftTuple.resetByTupleOffset(copy.leftPageBuf, 0);
+
+        copy.rightPageData = rightPageData.clone();
+        copy.rightPageBuf = ByteBuffer.wrap(copy.rightPageData);
+        copy.rightTuple.setFieldCount(rightTuple.getFieldCount());
+        copy.rightTuple.resetByTupleOffset(copy.rightPageBuf, 0);
+        return copy;
+    }
+
+    @Override
+    public void reset() {
+        leftPageData = null;
+        leftPageBuf = null;
+        rightPageData = null;
+        rightPageBuf = null;
+    }
+
+    @Override
+    public ByteBuffer getBuffer() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    @Override
+    public ITreeIndexTupleReference getTuple() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    @Override
+    public void setPages(int leftPage, int rightPage) {
+        leftPageBuf.putInt(keySize, leftPage);
+        rightPageBuf.putInt(keySize, rightPage);
+    }
+
+    @Override
+    public ISplitKey duplicate(ITreeIndexTupleReference copyTuple) {
+        // TODO Auto-generated method stub
+        return null;
+    }
+}
\ No newline at end of file
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/Rectangle.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/Rectangle.java
new file mode 100644
index 0000000..1fb86a9
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/Rectangle.java
@@ -0,0 +1,136 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.DoubleSerializerDeserializer;
+
+public class Rectangle {
+    private int dim;
+    private double[] low;
+    private double[] high;
+
+    public Rectangle(int dim) {
+        this.dim = dim;
+        low = new double[this.dim];
+        high = new double[this.dim];
+    }
+
+    public int getDim() {
+        return dim;
+    }
+
+    public double getLow(int i) {
+        return low[i];
+    }
+
+    public double getHigh(int i) {
+        return high[i];
+    }
+
+    public void setLow(int i, double value) {
+        low[i] = value;
+    }
+
+    public void setHigh(int i, double value) {
+        high[i] = value;
+    }
+
+    public void set(ITupleReference tuple) {
+        for (int i = 0; i < getDim(); i++) {
+            int j = i + getDim();
+            setLow(i, DoubleSerializerDeserializer.getDouble(tuple.getFieldData(i), tuple.getFieldStart(i)));
+            setHigh(i, DoubleSerializerDeserializer.getDouble(tuple.getFieldData(j), tuple.getFieldStart(j)));
+        }
+    }
+
+    public void enlarge(ITupleReference tupleToBeInserted) {
+        for (int i = 0; i < getDim(); i++) {
+            int j = getDim() + i;
+            double low = DoubleSerializerDeserializer.getDouble(tupleToBeInserted.getFieldData(i),
+                    tupleToBeInserted.getFieldStart(i));
+            if (getLow(i) > low) {
+                setLow(i, low);
+            }
+            double high = DoubleSerializerDeserializer.getDouble(tupleToBeInserted.getFieldData(j),
+                    tupleToBeInserted.getFieldStart(j));
+            if (getHigh(i) < high) {
+                setHigh(i, high);
+            }
+        }
+    }
+
+    public double margin() {
+        double margin = 0.0;
+        double mul = Math.pow(2, (double) getDim() - 1.0);
+        for (int i = 0; i < getDim(); i++) {
+            margin += (getHigh(i) - getLow(i)) * mul;
+        }
+        return margin;
+    }
+
+    public double overlappedArea(ITupleReference tuple) {
+        double area = 1.0;
+        double f1, f2;
+
+        for (int i = 0; i < getDim(); i++) {
+            int j = getDim() + i;
+            double low = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(i), tuple.getFieldStart(i));
+            double high = DoubleSerializerDeserializer.getDouble(tuple.getFieldData(j), tuple.getFieldStart(j));
+            if (getLow(i) > high || getHigh(i) < low) {
+                return 0.0;
+            }
+            f1 = Math.max(getLow(i), low);
+            f2 = Math.min(getHigh(i), high);
+            area *= f2 - f1;
+        }
+        return area;
+    }
+
+    public double overlappedArea(Rectangle rec) {
+        double area = 1.0;
+        double f1, f2;
+
+        for (int i = 0; i < getDim(); i++) {
+            if (getLow(i) > rec.getHigh(i) || getHigh(i) < rec.getLow(i)) {
+                return 0.0;
+            }
+
+            f1 = Math.max(getLow(i), rec.getLow(i));
+            f2 = Math.min(getHigh(i), rec.getHigh(i));
+            area *= f2 - f1;
+        }
+        return area;
+    }
+
+    public double area(ITupleReference tuple) {
+        double area = 1.0;
+        for (int i = 0; i < getDim(); i++) {
+            int j = getDim() + i;
+            area *= DoubleSerializerDeserializer.getDouble(tuple.getFieldData(j), tuple.getFieldStart(j))
+                    - DoubleSerializerDeserializer.getDouble(tuple.getFieldData(i), tuple.getFieldStart(i));
+        }
+        return area;
+    }
+
+    public double area() {
+        double area = 1.0;
+        for (int i = 0; i < getDim(); i++) {
+            area *= getHigh(i) - getLow(i);
+        }
+        return area;
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/SearchPredicate.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/SearchPredicate.java
new file mode 100644
index 0000000..cd3a0ef
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/SearchPredicate.java
@@ -0,0 +1,49 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ISearchPredicate;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+
+public class SearchPredicate implements ISearchPredicate {
+
+    private static final long serialVersionUID = 1L;
+
+    protected ITupleReference searchKey;
+    protected MultiComparator cmp;
+
+    public SearchPredicate(ITupleReference searchKey, MultiComparator cmp) {
+        this.searchKey = searchKey;
+        this.cmp = cmp;
+    }
+
+    public ITupleReference getSearchKey() {
+        return searchKey;
+    }
+
+    public void setSearchKey(ITupleReference searchKey) {
+        this.searchKey = searchKey;
+    }
+
+    public MultiComparator getLowKeyComparator() {
+        return cmp;
+    }
+
+    public MultiComparator getHighKeyComparator() {
+        return cmp;
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/TupleEntry.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/TupleEntry.java
new file mode 100644
index 0000000..0cb3de8
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/TupleEntry.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreeNSMFrame;
+
+public class TupleEntry implements Comparable<TupleEntry> {
+    private int tupleIndex;
+    private double value;
+
+    public TupleEntry() {
+    }
+
+    public int getTupleIndex() {
+        return tupleIndex;
+    }
+
+    public void setTupleIndex(int tupleIndex) {
+        this.tupleIndex = tupleIndex;
+    }
+
+    public double getValue() {
+        return value;
+    }
+
+    public void setValue(double value) {
+        this.value = value;
+    }
+
+    public int compareTo(TupleEntry tupleEntry) {
+        double cmp = this.getValue() - tupleEntry.getValue();
+        if (cmp > RTreeNSMFrame.doubleEpsilon())
+            return 1;
+        cmp = tupleEntry.getValue() - this.getValue();
+        if (cmp > RTreeNSMFrame.doubleEpsilon())
+            return -1;
+        return 0;
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/TupleEntryArrayList.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/TupleEntryArrayList.java
new file mode 100644
index 0000000..8be8251
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/TupleEntryArrayList.java
@@ -0,0 +1,79 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import java.util.Arrays;
+import java.util.Collections;
+
+public class TupleEntryArrayList {
+    private TupleEntry[] data;
+    private int size;
+    private final int growth;
+
+    public TupleEntryArrayList(int initialCapacity, int growth) {
+        data = new TupleEntry[initialCapacity];
+        size = 0;
+        this.growth = growth;
+    }
+
+    public int size() {
+        return size;
+    }
+
+    public void add(int tupleIndex, double value) {
+        if (size == data.length) {
+            TupleEntry[] newData = new TupleEntry[data.length + growth];
+            System.arraycopy(data, 0, newData, 0, data.length);
+            data = newData;
+        }
+        if (data[size] == null) {
+            data[size] = new TupleEntry();
+        }
+        data[size].setTupleIndex(tupleIndex);
+        data[size].setValue(value);
+        size++;
+    }
+
+    public void removeLast() {
+        if (size > 0)
+            size--;
+    }
+
+    // WARNING: caller is responsible for checking size > 0
+    public TupleEntry getLast() {
+        return data[size - 1];
+    }
+
+    public TupleEntry get(int i) {
+        return data[i];
+    }
+
+    public void clear() {
+        size = 0;
+    }
+
+    public boolean isEmpty() {
+        return size == 0;
+    }
+
+    public void sort(EntriesOrder order, int tupleCount) {
+        if (order == EntriesOrder.ASCENDING) {
+            Arrays.sort(data, 0, tupleCount);
+        } else {
+            Arrays.sort(data, 0, tupleCount, Collections.reverseOrder());
+        }
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/UnorderedSlotManager.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/UnorderedSlotManager.java
new file mode 100644
index 0000000..d2b1c53
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/impls/UnorderedSlotManager.java
@@ -0,0 +1,114 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.impls;
+
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.frames.AbstractSlotManager;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleMode;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.FindTupleNoExactMatchPolicy;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreeNSMFrame;
+
+public class UnorderedSlotManager extends AbstractSlotManager {
+    @Override
+    public int findTupleIndex(ITupleReference searchKey, ITreeIndexTupleReference frameTuple, MultiComparator multiCmp,
+            FindTupleMode mode, FindTupleNoExactMatchPolicy matchPolicy) {
+
+        int maxFieldPos = multiCmp.getKeyFieldCount() / 2;
+        for (int i = 0; i < frame.getTupleCount(); i++) {
+            frameTuple.resetByTupleIndex(frame, i);
+
+            boolean foundTuple = true;
+            for (int j = 0; j < maxFieldPos; j++) {
+                int k = maxFieldPos + j;
+                int c1 = multiCmp.getComparators()[j].compare(frameTuple.getFieldData(j), frameTuple.getFieldStart(j),
+                        frameTuple.getFieldLength(j), searchKey.getFieldData(j), searchKey.getFieldStart(j),
+                        searchKey.getFieldLength(j));
+
+                if (c1 != 0) {
+                    foundTuple = false;
+                    break;
+                }
+                int c2 = multiCmp.getComparators()[k].compare(frameTuple.getFieldData(k), frameTuple.getFieldStart(k),
+                        frameTuple.getFieldLength(k), searchKey.getFieldData(k), searchKey.getFieldStart(k),
+                        searchKey.getFieldLength(k));
+                if (c2 != 0) {
+                    foundTuple = false;
+                    break;
+                }
+            }
+            int remainingFieldCount = multiCmp.getFieldCount() - multiCmp.getKeyFieldCount();
+            for (int j = multiCmp.getKeyFieldCount(); j < multiCmp.getKeyFieldCount() + remainingFieldCount; j++) {
+                if (!compareField(searchKey, frameTuple, j)) {
+                    foundTuple = false;
+                    break;
+                }
+            }
+            if (foundTuple) {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    public boolean compareField(ITupleReference searchKey, ITreeIndexTupleReference frameTuple, int fIdx) {
+        int searchKeyFieldLength = searchKey.getFieldLength(fIdx);
+        int frameTupleFieldLength = frameTuple.getFieldLength(fIdx);
+
+        if (searchKeyFieldLength != frameTupleFieldLength) {
+            return false;
+        }
+
+        for (int i = 0; i < searchKeyFieldLength; i++) {
+            if (searchKey.getFieldData(fIdx)[i + searchKey.getFieldStart(fIdx)] != frameTuple.getFieldData(fIdx)[i
+                    + frameTuple.getFieldStart(fIdx)]) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public int insertSlot(int tupleIndex, int tupleOff) {
+        int slotOff = getSlotEndOff() - slotSize;
+        setSlot(slotOff, tupleOff);
+        return slotOff;
+    }
+
+    public void modifySlot(int slotOff, int tupleOff) {
+        setSlot(slotOff, tupleOff);
+    }
+
+    public void deleteEmptySlots() {
+        int slotOff = getSlotStartOff();
+        while (slotOff >= getSlotEndOff()) {
+            if (frame.getBuffer().getInt(slotOff) == -1) {
+                while (frame.getBuffer().getInt(getSlotEndOff()) == -1) {
+                    ((RTreeNSMFrame) frame).setTupleCount(frame.getTupleCount() - 1);
+                }
+                if (slotOff > getSlotEndOff()) {
+                    System.arraycopy(frame.getBuffer().array(), getSlotEndOff(), frame.getBuffer().array(), slotOff,
+                            slotSize);
+                    ((RTreeNSMFrame) frame).setTupleCount(frame.getTupleCount() - 1);
+                } else {
+                    break;
+                }
+            }
+            slotOff -= slotSize;
+        }
+    }
+}
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/tuples/RTreeTypeAwareTupleWriter.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/tuples/RTreeTypeAwareTupleWriter.java
new file mode 100644
index 0000000..96820c9
--- /dev/null
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/tuples/RTreeTypeAwareTupleWriter.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree.tuples;
+
+import java.nio.ByteBuffer;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleReference;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriter;
+
+public class RTreeTypeAwareTupleWriter extends TypeAwareTupleWriter {
+
+    public RTreeTypeAwareTupleWriter(ITypeTrait[] typeTraits) {
+        super(typeTraits);
+    }
+
+    public int writeTupleFields(ITreeIndexTupleReference[] refs, int startField, ByteBuffer targetBuf, int targetOff) {
+        int runner = targetOff;
+        int nullFlagsBytes = getNullFlagsBytes(refs.length);
+        // write null indicator bits
+        for (int i = 0; i < nullFlagsBytes; i++) {
+            targetBuf.put(runner++, (byte) 0);
+        }
+
+        // write field slots for variable length fields
+        // since the r-tree has fixed length keys, we don't actually need this?
+        encDec.reset(targetBuf.array(), runner);
+        for (int i = startField; i < startField + refs.length; i++) {
+            if (typeTraits[i].getStaticallyKnownDataLength() == ITypeTrait.VARIABLE_LENGTH) {
+                encDec.encode(refs[i].getFieldLength(i));
+            }
+        }
+        runner = encDec.getPos();
+
+        // write data
+        for (int i = 0; i < refs.length; i++) {
+            System.arraycopy(refs[i].getFieldData(i), refs[i].getFieldStart(i), targetBuf.array(), runner,
+                    refs[i].getFieldLength(i));
+            runner += refs[i].getFieldLength(i);
+        }
+        return runner - targetOff;
+
+    }
+}
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriterFactory.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/tuples/RTreeTypeAwareTupleWriterFactory.java
similarity index 64%
copy from hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriterFactory.java
copy to hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/tuples/RTreeTypeAwareTupleWriterFactory.java
index bfaa120..e2e99c7 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriterFactory.java
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/tuples/RTreeTypeAwareTupleWriterFactory.java
@@ -13,24 +13,24 @@
  * limitations under the License.
  */
 
-package edu.uci.ics.hyracks.storage.am.btree.tuples;
+package edu.uci.ics.hyracks.storage.am.rtree.tuples;
 
 import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriterFactory;
 
-public class TypeAwareTupleWriterFactory implements IBTreeTupleWriterFactory {
+public class RTreeTypeAwareTupleWriterFactory implements ITreeIndexTupleWriterFactory {
 
     private static final long serialVersionUID = 1L;
     private ITypeTrait[] typeTraits;
 
-    public TypeAwareTupleWriterFactory(ITypeTrait[] typeTraits) {
+    public RTreeTypeAwareTupleWriterFactory(ITypeTrait[] typeTraits) {
         this.typeTraits = typeTraits;
     }
 
     @Override
-    public IBTreeTupleWriter createTupleWriter() {
-        return new TypeAwareTupleWriter(typeTraits);
+    public ITreeIndexTupleWriter createTupleWriter() {
+        return new RTreeTypeAwareTupleWriter(typeTraits);
     }
 
 }
diff --git a/hyracks-storage-common/.settings/org.eclipse.jdt.core.prefs b/hyracks-storage-common/.settings/org.eclipse.jdt.core.prefs
index 33fff33..450f5c4 100644
--- a/hyracks-storage-common/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-storage-common/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Tue Aug 24 14:59:46 PDT 2010
+#Fri May 20 19:34:04 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/BufferCache.java b/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/BufferCache.java
index c2693ab..f9ac4d5 100644
--- a/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/BufferCache.java
+++ b/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/BufferCache.java
@@ -39,6 +39,8 @@
 
     private static final int MAX_VICTIMIZATION_TRY_COUNT = 3;
 
+    private final int maxOpenFiles;
+    
     private final IIOManager ioManager;
     private final int pageSize;
     private final int numPages;
@@ -52,10 +54,11 @@
     private boolean closed;
 
     public BufferCache(IIOManager ioManager, ICacheMemoryAllocator allocator,
-            IPageReplacementStrategy pageReplacementStrategy, IFileMapManager fileMapManager, int pageSize, int numPages) {
+            IPageReplacementStrategy pageReplacementStrategy, IFileMapManager fileMapManager, int pageSize, int numPages, int maxOpenFiles) {
         this.ioManager = ioManager;
         this.pageSize = pageSize;
         this.numPages = numPages;
+        this.maxOpenFiles = maxOpenFiles;
         pageReplacementStrategy.setBufferCache(this);
         ByteBuffer[] buffers = allocator.allocate(pageSize, numPages);
         cachedPages = new CachedPage[buffers.length];
@@ -84,11 +87,50 @@
         return numPages;
     }
 
-    @Override
-    public ICachedPage pin(long dpid, boolean newPage) throws HyracksDataException {
+    private void pinSanityCheck(long dpid) throws HyracksDataException {
         if (closed) {
             throw new HyracksDataException("pin called on a closed cache");
         }
+        
+        // check whether file has been created and opened
+        int fileId = BufferedFileHandle.getFileId(dpid);
+        BufferedFileHandle fInfo = fileInfoMap.get(fileId);
+        if(fInfo == null) {
+            throw new HyracksDataException("pin called on a fileId " + fileId + " that has not been created.");
+        } else if(fInfo.getReferenceCount() <= 0) {
+            throw new HyracksDataException("pin called on a fileId " + fileId + " that has not been opened.");
+        }
+    }
+    
+    @Override 
+    public ICachedPage tryPin(long dpid) throws HyracksDataException {        
+        pinSanityCheck(dpid);
+        
+        CachedPage cPage = null;
+        int hash = hash(dpid);
+        CacheBucket bucket = pageMap[hash];
+        bucket.bucketLock.lock();
+        try {
+            cPage = bucket.cachedPage;
+            while (cPage != null) {
+                if (cPage.dpid == dpid) {
+                    cPage.pinCount.incrementAndGet();
+                    pageReplacementStrategy.notifyCachePageAccess(cPage);
+                    return cPage;
+                }
+                cPage = cPage.next;
+            }
+        } finally {
+            bucket.bucketLock.unlock();
+        }
+        
+        return cPage;
+    }
+    
+    @Override
+    public ICachedPage pin(long dpid, boolean newPage) throws HyracksDataException {
+        pinSanityCheck(dpid);
+        
         CachedPage cPage = findPage(dpid, newPage);
         if (!newPage) {
             if (!cPage.valid) {
@@ -472,7 +514,7 @@
     }
 
     @Override
-    public void close() {
+    public void close() {        
         closed = true;
         synchronized (cleanerThread) {
             cleanerThread.shutdownStart = true;
@@ -484,7 +526,19 @@
                     e.printStackTrace();
                 }
             }
-        }
+        }    
+        
+        synchronized (fileInfoMap) {
+            try {
+                for(Map.Entry<Integer, BufferedFileHandle> entry : fileInfoMap.entrySet()) {
+                    sweepAndFlush(entry.getKey());
+                    ioManager.close(entry.getValue().getFileHandle());
+                }
+            } catch(HyracksDataException e) {
+                e.printStackTrace();
+            }
+            fileInfoMap.clear();
+        }        
     }
 
     @Override
@@ -506,6 +560,29 @@
             BufferedFileHandle fInfo;
             fInfo = fileInfoMap.get(fileId);
             if (fInfo == null) {
+                
+                // map is full, make room by removing cleaning up unreferenced files
+                boolean unreferencedFileFound = true;
+                while(fileInfoMap.size() >= maxOpenFiles && unreferencedFileFound) {                
+                    unreferencedFileFound = false;                    
+                    for(Map.Entry<Integer, BufferedFileHandle> entry : fileInfoMap.entrySet()) {
+                        if(entry.getValue().getReferenceCount() <= 0) {
+                            int entryFileId = entry.getKey();
+                            sweepAndFlush(entryFileId);
+                            fileInfoMap.remove(entryFileId);
+                            ioManager.close(entry.getValue().getFileHandle());
+                            unreferencedFileFound = true;
+                            // for-each iterator is invalid because we changed fileInfoMap
+                            break;
+                        }
+                    }
+                }
+                
+                if(fileInfoMap.size() >= maxOpenFiles) {
+                    throw new HyracksDataException("Could not open fileId " + fileId + ". Max number of files " + maxOpenFiles + " already opened and referenced.");
+                }
+                
+                // create, open, and map new file reference
                 FileReference fileRef = fileMapManager.lookupFileName(fileId);
                 FileHandle fh = ioManager.open(fileRef, IIOManager.FileReadWriteMode.READ_WRITE,
                         IIOManager.FileSyncMode.METADATA_ASYNC_DATA_ASYNC);
@@ -515,7 +592,7 @@
             fInfo.incReferenceCount();
         }
     }
-
+        
     private void sweepAndFlush(int fileId) throws HyracksDataException {
         for (int i = 0; i < pageMap.length; ++i) {
             CacheBucket bucket = pageMap[i];
@@ -574,10 +651,8 @@
             if (fInfo == null) {
                 throw new HyracksDataException("Closing unopened file");
             }
-            if (fInfo.decReferenceCount() <= 0) {
-                sweepAndFlush(fileId);
-                fileInfoMap.remove(fileId);
-                ioManager.close(fInfo.getFileHandle());
+            if (fInfo.decReferenceCount() < 0) {
+                throw new HyracksDataException("Closed fileId: " + fileId + " more times than it was opened.");                                
             }
         }
     }
diff --git a/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/IBufferCache.java b/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/IBufferCache.java
index b21c054..e82c01b 100644
--- a/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/IBufferCache.java
+++ b/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/buffercache/IBufferCache.java
@@ -26,6 +26,8 @@
 
     public void deleteFile(int fileId) throws HyracksDataException;
 
+    public ICachedPage tryPin(long dpid) throws HyracksDataException;
+
     public ICachedPage pin(long dpid, boolean newPage) throws HyracksDataException;
 
     public void unpin(ICachedPage page) throws HyracksDataException;
diff --git a/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/file/BufferedFileHandle.java b/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/file/BufferedFileHandle.java
index 1db0bf7..3137f20 100644
--- a/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/file/BufferedFileHandle.java
+++ b/hyracks-storage-common/src/main/java/edu/uci/ics/hyracks/storage/common/file/BufferedFileHandle.java
@@ -44,6 +44,10 @@
     public int decReferenceCount() {
         return refCount.decrementAndGet();
     }
+    
+    public int getReferenceCount() {
+        return refCount.get();
+    }
 
     public long getDiskPageId(int pageId) {
         return getDiskPageId(fileId, pageId);
diff --git a/hyracks-test-support/.settings/org.eclipse.jdt.core.prefs b/hyracks-test-support/.settings/org.eclipse.jdt.core.prefs
index 18b0312..375e12e 100644
--- a/hyracks-test-support/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-test-support/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Wed Jan 05 15:09:31 PST 2011
+#Fri May 20 19:34:07 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestStorageManagerComponentHolder.java b/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestStorageManagerComponentHolder.java
index 5338d5e..2325db7 100644
--- a/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestStorageManagerComponentHolder.java
+++ b/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestStorageManagerComponentHolder.java
@@ -15,7 +15,8 @@
 package edu.uci.ics.hyracks.test.support;
 
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeRegistry;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexRegistry;
 import edu.uci.ics.hyracks.storage.common.buffercache.BufferCache;
 import edu.uci.ics.hyracks.storage.common.buffercache.ClockPageReplacementStrategy;
 import edu.uci.ics.hyracks.storage.common.buffercache.HeapBufferAllocator;
@@ -29,17 +30,19 @@
 public class TestStorageManagerComponentHolder {
     private static IBufferCache bufferCache;
     private static IFileMapProvider fileMapProvider;
-    private static BTreeRegistry btreeRegistry;
+    private static IndexRegistry<ITreeIndex> treeIndexRegistry;
 
     private static int pageSize;
     private static int numPages;
+    private static int maxOpenFiles;
 
-    public static void init(int pageSize, int numPages) {
+    public static void init(int pageSize, int numPages, int maxOpenFiles) {
         TestStorageManagerComponentHolder.pageSize = pageSize;
         TestStorageManagerComponentHolder.numPages = numPages;
+        TestStorageManagerComponentHolder.maxOpenFiles = maxOpenFiles;
         bufferCache = null;
         fileMapProvider = null;
-        btreeRegistry = null;
+        treeIndexRegistry = null;
     }
 
     public synchronized static IBufferCache getBufferCache(IHyracksStageletContext ctx) {
@@ -48,7 +51,7 @@
             IPageReplacementStrategy prs = new ClockPageReplacementStrategy();
             IFileMapProvider fileMapProvider = getFileMapProvider(ctx);
             bufferCache = new BufferCache(ctx.getIOManager(), allocator, prs, (IFileMapManager) fileMapProvider,
-                    pageSize, numPages);
+                    pageSize, numPages, maxOpenFiles);
         }
         return bufferCache;
     }
@@ -60,10 +63,10 @@
         return fileMapProvider;
     }
 
-    public synchronized static BTreeRegistry getBTreeRegistry(IHyracksStageletContext ctx) {
-        if (btreeRegistry == null) {
-            btreeRegistry = new BTreeRegistry();
+    public synchronized static IndexRegistry<ITreeIndex> getTreeIndexRegistry(IHyracksStageletContext ctx) {
+        if (treeIndexRegistry == null) {
+        	treeIndexRegistry = new IndexRegistry<ITreeIndex>();
         }
-        return btreeRegistry;
+        return treeIndexRegistry;
     }
 }
\ No newline at end of file
diff --git a/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestBTreeRegistryProvider.java b/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestTreeIndexRegistryProvider.java
similarity index 63%
rename from hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestBTreeRegistryProvider.java
rename to hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestTreeIndexRegistryProvider.java
index 3ab0427..630f47f 100644
--- a/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestBTreeRegistryProvider.java
+++ b/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestTreeIndexRegistryProvider.java
@@ -15,14 +15,15 @@
 package edu.uci.ics.hyracks.test.support;
 
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.BTreeRegistry;
-import edu.uci.ics.hyracks.storage.am.btree.dataflow.IBTreeRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexRegistryProvider;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexRegistry;
 
-public class TestBTreeRegistryProvider implements IBTreeRegistryProvider {
+public class TestTreeIndexRegistryProvider implements IIndexRegistryProvider<ITreeIndex> {
     private static final long serialVersionUID = 1L;
-
-    @Override
-    public BTreeRegistry getBTreeRegistry(IHyracksStageletContext ctx) {
-        return TestStorageManagerComponentHolder.getBTreeRegistry(ctx);
-    }
+    
+	@Override
+	public IndexRegistry<ITreeIndex> getRegistry(IHyracksStageletContext ctx) {
+		return TestStorageManagerComponentHolder.getTreeIndexRegistry(ctx);
+	}
 }
\ No newline at end of file
diff --git a/hyracks-tests/hyracks-storage-am-btree-test/.settings/org.eclipse.jdt.core.prefs b/hyracks-tests/hyracks-storage-am-btree-test/.settings/org.eclipse.jdt.core.prefs
index 3cd389e..7cf8ad6 100644
--- a/hyracks-tests/hyracks-storage-am-btree-test/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-tests/hyracks-storage-am-btree-test/.settings/org.eclipse.jdt.core.prefs
@@ -1,6 +1,264 @@
-#Thu Jan 06 11:27:16 PST 2011
+#Fri May 20 19:34:07 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
 org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
 org.eclipse.jdt.core.compiler.source=1.6
+org.eclipse.jdt.core.formatter.align_type_members_on_columns=false
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diff --git a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/AbstractBTreeTest.java b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/AbstractBTreeTest.java
index c2e2fd6..56ae6e9 100644
--- a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/AbstractBTreeTest.java
+++ b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/AbstractBTreeTest.java
@@ -3,11 +3,14 @@
 import java.io.File;
 import java.text.SimpleDateFormat;
 import java.util.Date;
+import java.util.logging.Logger;
 
 import org.junit.AfterClass;
 
 public abstract class AbstractBTreeTest {
 
+    protected static final Logger LOGGER = Logger.getLogger(AbstractBTreeTest.class.getName());
+
     protected final static SimpleDateFormat simpleDateFormat = new SimpleDateFormat("ddMMyy-hhmmssSS");
     protected final static String tmpDir = System.getProperty("java.io.tmpdir");
     protected final static String sep = System.getProperty("file.separator");
diff --git a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeFieldPrefixNSMTest.java b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeFieldPrefixNSMTest.java
index e856296..2b2bf55 100644
--- a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeFieldPrefixNSMTest.java
+++ b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeFieldPrefixNSMTest.java
@@ -39,15 +39,14 @@
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 import edu.uci.ics.hyracks.dataflow.common.data.comparators.IntegerBinaryComparatorFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeTupleWriter;
 import edu.uci.ics.hyracks.storage.am.btree.api.IPrefixSlotManager;
-import edu.uci.ics.hyracks.storage.am.btree.frames.FieldPrefixNSMLeafFrame;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrame;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeException;
 import edu.uci.ics.hyracks.storage.am.btree.impls.FieldPrefixSlotManager;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexTupleWriter;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriter;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
-import edu.uci.ics.hyracks.storage.common.buffercache.ICacheMemoryAllocator;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
 import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
@@ -58,24 +57,14 @@
 
 	private static final int PAGE_SIZE = 32768; // 32K
 	private static final int NUM_PAGES = 40;
+	private static final int MAX_OPEN_FILES = 10;
 	private static final int HYRACKS_FRAME_SIZE = 128;
 	private IHyracksStageletContext ctx = TestUtils.create(HYRACKS_FRAME_SIZE);
-	
-	public class BufferAllocator implements ICacheMemoryAllocator {
-		@Override
-		public ByteBuffer[] allocate(int pageSize, int numPages) {
-			ByteBuffer[] buffers = new ByteBuffer[numPages];
-			for (int i = 0; i < numPages; ++i) {
-				buffers[i] = ByteBuffer.allocate(pageSize);
-			}
-			return buffers;
-		}
-	}
-
+		
 	private ITupleReference createTuple(IHyracksStageletContext ctx, int f0,
 			int f1, int f2, boolean print) throws HyracksDataException {
 		if (print)
-			System.out.println("CREATING: " + f0 + " " + f1 + " " + f2);
+		    LOGGER.info("CREATING: " + f0 + " " + f1 + " " + f2);		
 
 		ByteBuffer buf = ctx.allocateFrame();
 		FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
@@ -112,7 +101,7 @@
 	@Test
 	public void test01() throws Exception {
 		
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
+		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
 		IBufferCache bufferCache = TestStorageManagerComponentHolder
 				.getBufferCache(ctx);
 		IFileMapProvider fmp = TestStorageManagerComponentHolder
@@ -154,8 +143,8 @@
 		try {
 
 			IPrefixSlotManager slotManager = new FieldPrefixSlotManager();
-			IBTreeTupleWriter tupleWriter = new TypeAwareTupleWriter(typeTraits);
-			FieldPrefixNSMLeafFrame frame = new FieldPrefixNSMLeafFrame(
+			ITreeIndexTupleWriter tupleWriter = new TypeAwareTupleWriter(typeTraits);
+			BTreeFieldPrefixNSMLeafFrame frame = new BTreeFieldPrefixNSMLeafFrame(
 					tupleWriter);
 			frame.setPage(page);
 			frame.initBuffer((byte) 0);
@@ -176,7 +165,7 @@
 			for (int i = 0; i < numRecords; i++) {
 
 				if ((i + 1) % 100 == 0)
-					print("INSERTING " + (i + 1) + " / " + numRecords + "\n");
+					LOGGER.info("INSERTING " + (i + 1) + " / " + numRecords);
 
 				int a = rnd.nextInt() % smallMax;
 				int b = rnd.nextInt() % smallMax;
@@ -184,7 +173,8 @@
 
 				ITupleReference tuple = createTuple(ctx, a, b, c, false);
 				try {
-					frame.insert(tuple, cmp);
+					int targetTupleIndex = frame.findTupleIndex(tuple, cmp);
+					frame.insert(tuple, cmp, targetTupleIndex);
 				} catch (BTreeException e) {
 					e.printStackTrace();
 				} catch (Exception e) {
@@ -215,7 +205,7 @@
 			for (int i = 0; i < numRecords; i++) {
 
 				if ((i + 1) % 100 == 0)
-					print("DELETING " + (i + 1) + " / " + numRecords + "\n");
+					LOGGER.info("DELETING " + (i + 1) + " / " + numRecords);
 
 				ITupleReference tuple = createTuple(ctx,
 						savedFields[i][0], savedFields[i][1],
diff --git a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeStatsTest.java b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeStatsTest.java
new file mode 100644
index 0000000..44cf18b
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeStatsTest.java
@@ -0,0 +1,173 @@
+package edu.uci.ics.hyracks.storage.am.btree;
+
+import java.io.DataOutput;
+import java.io.File;
+import java.nio.ByteBuffer;
+import java.util.Random;
+
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.dataflow.value.TypeTrait;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.FrameTupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.IntegerBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
+import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.freepage.LinkedListFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.common.utility.TreeIndexBufferCacheWarmup;
+import edu.uci.ics.hyracks.storage.am.common.utility.TreeIndexStats;
+import edu.uci.ics.hyracks.storage.am.common.utility.TreeIndexStatsGatherer;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
+import edu.uci.ics.hyracks.test.support.TestUtils;
+
+public class BTreeStatsTest extends AbstractBTreeTest {
+
+	// private static final int PAGE_SIZE = 256;
+	// private static final int NUM_PAGES = 10;
+	// private static final int PAGE_SIZE = 32768;
+    private static final int PAGE_SIZE = 4096;
+    private static final int NUM_PAGES = 1000;
+    private static final int MAX_OPEN_FILES = 10;
+	private static final int HYRACKS_FRAME_SIZE = 128;
+	private IHyracksStageletContext ctx = TestUtils.create(HYRACKS_FRAME_SIZE);
+	
+	@Test
+	public void test01() throws Exception {
+
+		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+		IBufferCache bufferCache = TestStorageManagerComponentHolder
+				.getBufferCache(ctx);
+		IFileMapProvider fmp = TestStorageManagerComponentHolder
+				.getFileMapProvider(ctx);
+		FileReference file = new FileReference(new File(fileName));
+		bufferCache.createFile(file);
+		int fileId = fmp.lookupFileId(file);
+		bufferCache.openFile(fileId);
+
+		// declare fields
+		int fieldCount = 2;
+		ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+		typeTraits[0] = new TypeTrait(4);
+		typeTraits[1] = new TypeTrait(4);
+
+		// declare keys
+		int keyFieldCount = 1;
+		IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+		cmps[0] = IntegerBinaryComparatorFactory.INSTANCE
+				.createBinaryComparator();
+
+		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+
+		TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(
+				typeTraits);
+		ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(
+				tupleWriterFactory);
+		ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(
+				tupleWriterFactory);
+		ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
+
+		IBTreeLeafFrame leafFrame = (IBTreeLeafFrame)leafFrameFactory.createFrame();
+		IBTreeInteriorFrame interiorFrame = (IBTreeInteriorFrame)interiorFrameFactory.createFrame();
+		ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
+
+		IFreePageManager freePageManager = new LinkedListFreePageManager(
+				bufferCache, fileId, 0, metaFrameFactory);
+
+		BTree btree = new BTree(bufferCache, freePageManager,
+				interiorFrameFactory, leafFrameFactory, cmp);
+		btree.create(fileId, leafFrame, metaFrame);
+		btree.open(fileId);
+
+		Random rnd = new Random();
+		rnd.setSeed(50);
+
+		long start = System.currentTimeMillis();
+
+		LOGGER.info("INSERTING INTO TREE");
+
+		ByteBuffer frame = ctx.allocateFrame();
+		FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+		DataOutput dos = tb.getDataOutput();
+
+		ISerializerDeserializer[] recDescSers = {
+				IntegerSerializerDeserializer.INSTANCE,
+				IntegerSerializerDeserializer.INSTANCE };
+		RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+		IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx
+				.getFrameSize(), recDesc);
+		accessor.reset(frame);
+		FrameTupleReference tuple = new FrameTupleReference();
+
+		BTreeOpContext insertOpCtx = btree.createOpContext(
+				IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
+
+		// 10000
+		for (int i = 0; i < 100000; i++) {
+
+			int f0 = rnd.nextInt() % 100000;
+			int f1 = 5;
+
+			tb.reset();
+			IntegerSerializerDeserializer.INSTANCE.serialize(f0, dos);
+			tb.addFieldEndOffset();
+			IntegerSerializerDeserializer.INSTANCE.serialize(f1, dos);
+			tb.addFieldEndOffset();
+
+			appender.reset(frame, true);
+			appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb
+					.getSize());
+
+			tuple.reset(accessor, 0);
+			
+			if (i % 10000 == 0) {
+				long end = System.currentTimeMillis();
+				LOGGER.info("INSERTING " + i + " : " + f0 + " " + f1 + " "
+						+ (end - start));
+			}
+
+			try {
+				btree.insert(tuple, insertOpCtx);
+			} catch (TreeIndexException e) {
+			} catch (Exception e) {
+				e.printStackTrace();
+			}			
+		}
+		
+		TreeIndexStatsGatherer statsGatherer = new TreeIndexStatsGatherer(bufferCache, freePageManager, fileId, btree.getRootPageId());		
+		TreeIndexStats stats = statsGatherer.gatherStats(leafFrame, interiorFrame, metaFrame);
+		LOGGER.info(stats.toString());
+
+		TreeIndexBufferCacheWarmup bufferCacheWarmup = new TreeIndexBufferCacheWarmup(bufferCache, freePageManager, fileId);
+		bufferCacheWarmup.warmup(leafFrame, metaFrame, new int[] {1, 2}, new int[] {2, 5});
+		
+		btree.close();
+		bufferCache.closeFile(fileId);
+		bufferCache.close();
+	}
+}
diff --git a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeTest.java b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeTest.java
index 2985601..6fa5d43 100644
--- a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeTest.java
+++ b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/BTreeTest.java
@@ -39,1302 +39,1152 @@
 import edu.uci.ics.hyracks.dataflow.common.data.comparators.UTF8StringBinaryComparatorFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeCursor;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.MetaDataFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeException;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
-import edu.uci.ics.hyracks.storage.am.btree.impls.DiskOrderScanCursor;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeRangeSearchCursor;
 import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
-import edu.uci.ics.hyracks.storage.am.btree.impls.RangeSearchCursor;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.SimpleTupleWriterFactory;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.IIndexBulkLoadContext;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.freepage.LinkedListFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.impls.TreeDiskOrderScanCursor;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.SimpleTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
-import edu.uci.ics.hyracks.storage.common.buffercache.ICacheMemoryAllocator;
 import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
 import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
 import edu.uci.ics.hyracks.test.support.TestUtils;
 
-@SuppressWarnings("unchecked")
 public class BTreeTest extends AbstractBTreeTest {
 
-	private static final int PAGE_SIZE = 256;
-	private static final int NUM_PAGES = 10;
-	private static final int HYRACKS_FRAME_SIZE = 128;
-	private IHyracksStageletContext ctx = TestUtils.create(HYRACKS_FRAME_SIZE);
+    private static final int PAGE_SIZE = 256;
+    private static final int NUM_PAGES = 10;
+    private static final int MAX_OPEN_FILES = 10;
+    private static final int HYRACKS_FRAME_SIZE = 128;
+    private IHyracksStageletContext ctx = TestUtils.create(HYRACKS_FRAME_SIZE);
 
-	public class BufferAllocator implements ICacheMemoryAllocator {
-		@Override
-		public ByteBuffer[] allocate(int pageSize, int numPages) {
-			ByteBuffer[] buffers = new ByteBuffer[numPages];
-			for (int i = 0; i < numPages; ++i) {
-				buffers[i] = ByteBuffer.allocate(pageSize);
-			}
-			return buffers;
-		}
-	}
+    // FIXED-LENGTH KEY TEST
+    // create a B-tree with one fixed-length "key" field and one fixed-length
+    // "value" field
+    // fill B-tree with random values using insertions (not bulk load)
+    // perform ordered scan and range search
+    @Test
+    public void test01() throws Exception {
 
-	// FIXED-LENGTH KEY TEST
-	// create a B-tree with one fixed-length "key" field and one fixed-length
-	// "value" field
-	// fill B-tree with random values using insertions (not bulk load)
-	// perform ordered scan and range search
-	@Test
-	public void test01() throws Exception {
+        LOGGER.info("FIXED-LENGTH KEY TEST");
 
-		print("FIXED-LENGTH KEY TEST\n");
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
 
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
-		IBufferCache bufferCache = TestStorageManagerComponentHolder
-				.getBufferCache(ctx);
-		IFileMapProvider fmp = TestStorageManagerComponentHolder
-				.getFileMapProvider(ctx);
-		FileReference file = new FileReference(new File(fileName));
-		bufferCache.createFile(file);
-		int fileId = fmp.lookupFileId(file);
-		bufferCache.openFile(fileId);
+        // declare fields
+        int fieldCount = 2;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(4);
+        typeTraits[1] = new TypeTrait(4);
 
-		// declare fields
-		int fieldCount = 2;
-		ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
-		typeTraits[0] = new TypeTrait(4);
-		typeTraits[1] = new TypeTrait(4);
+        // declare keys
+        int keyFieldCount = 1;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
 
-		// declare keys
-		int keyFieldCount = 1;
-		IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
-		cmps[0] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
 
-		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+        TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
+        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
+        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
 
-		TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(
-				typeTraits);
-		// SimpleTupleWriterFactory tupleWriterFactory = new
-		// SimpleTupleWriterFactory();
-		IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(
-				tupleWriterFactory);
-		IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(
-				tupleWriterFactory);
-		IBTreeMetaDataFrameFactory metaFrameFactory = new MetaDataFrameFactory();
+        IBTreeLeafFrame leafFrame = (IBTreeLeafFrame) leafFrameFactory.createFrame();
+        IBTreeInteriorFrame interiorFrame = (IBTreeInteriorFrame) interiorFrameFactory.createFrame();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
 
-		IBTreeLeafFrame leafFrame = leafFrameFactory.getFrame();
-		IBTreeInteriorFrame interiorFrame = interiorFrameFactory.getFrame();
-		IBTreeMetaDataFrame metaFrame = metaFrameFactory.getFrame();
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
 
-		BTree btree = new BTree(bufferCache, interiorFrameFactory,
-				leafFrameFactory, cmp);
-		btree.create(fileId, leafFrame, metaFrame);
-		btree.open(fileId);
+        BTree btree = new BTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        btree.create(fileId, leafFrame, metaFrame);
+        btree.open(fileId);
 
-		Random rnd = new Random();
-		rnd.setSeed(50);
+        Random rnd = new Random();
+        rnd.setSeed(50);
 
-		long start = System.currentTimeMillis();
+        long start = System.currentTimeMillis();
 
-		print("INSERTING INTO TREE\n");
+        LOGGER.info("INSERTING INTO TREE");
 
-		ByteBuffer frame = ctx.allocateFrame();
-		FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
-		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
-		DataOutput dos = tb.getDataOutput();
+        ByteBuffer frame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
 
-		ISerializerDeserializer[] recDescSers = {
-				IntegerSerializerDeserializer.INSTANCE,
-				IntegerSerializerDeserializer.INSTANCE };
-		RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
-		IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), recDesc);
-		accessor.reset(frame);
-		FrameTupleReference tuple = new FrameTupleReference();
+        ISerializerDeserializer[] recDescSers = { IntegerSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(frame);
+        FrameTupleReference tuple = new FrameTupleReference();
 
-		BTreeOpContext insertOpCtx = btree.createOpContext(BTreeOp.BTO_INSERT,
-				leafFrame, interiorFrame, metaFrame);
+        BTreeOpContext insertOpCtx = btree.createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
 
-		// 10000
-		for (int i = 0; i < 10000; i++) {
+        // 10000
+        for (int i = 0; i < 10000; i++) {
 
-			int f0 = rnd.nextInt() % 10000;
-			int f1 = 5;
+            int f0 = rnd.nextInt() % 10000;
+            int f1 = 5;
 
-			tb.reset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(f0, dos);
-			tb.addFieldEndOffset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(f1, dos);
-			tb.addFieldEndOffset();
+            tb.reset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(f0, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(f1, dos);
+            tb.addFieldEndOffset();
 
-			appender.reset(frame, true);
-			appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb
-					.getSize());
+            appender.reset(frame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
 
-			tuple.reset(accessor, 0);
+            tuple.reset(accessor, 0);
 
-			// System.out.println(tuple.getFieldCount() + " " +
-			// tuple.getFieldLength(0) + " " + tuple.getFieldLength(1));
+            if (i % 1000 == 0) {
+                long end = System.currentTimeMillis();
+                LOGGER.info("INSERTING " + i + " : " + f0 + " " + f1 + " " + (end - start));
+            }
 
-			if (i % 1000 == 0) {
-				long end = System.currentTimeMillis();
-				print("INSERTING " + i + " : " + f0 + " " + f1 + " "
-						+ (end - start) + "\n");
-			}
+            try {
+                btree.insert(tuple, insertOpCtx);
+            } catch (TreeIndexException e) {
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+        // btree.printTree(leafFrame, interiorFrame);
 
-			try {
-				btree.insert(tuple, insertOpCtx);
-			} catch (BTreeException e) {
-			} catch (Exception e) {
-				e.printStackTrace();
-			}
+        int maxPage = btree.getFreePageManager().getMaxPage(metaFrame);
+        LOGGER.info("MAXPAGE: " + maxPage);
+        LOGGER.info(btree.printStats());        
+        
+        long end = System.currentTimeMillis();
+        long duration = end - start;
+        LOGGER.info("DURATION: " + duration);
 
-			// btree.printTree(leafFrame, interiorFrame);
-			// System.out.println();
-		}
-		// btree.printTree(leafFrame, interiorFrame);
-		// System.out.println();
+        // ordered scan
 
-		int maxPage = btree.getMaxPage(metaFrame);
-		System.out.println("MAXPAGE: " + maxPage);
+        LOGGER.info("ORDERED SCAN:");
+        ITreeIndexCursor scanCursor = new BTreeRangeSearchCursor(leafFrame);
+        RangePredicate nullPred = new RangePredicate(true, null, null, true, true, null, null);
+        BTreeOpContext searchOpCtx = btree.createOpContext(IndexOp.SEARCH, leafFrame, interiorFrame, null);
+        btree.search(scanCursor, nullPred, searchOpCtx);
+        try {
+            while (scanCursor.hasNext()) {
+                scanCursor.next();
+                ITupleReference frameTuple = scanCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                LOGGER.info(rec);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            scanCursor.close();
+        }
 
-		String stats = btree.printStats();
-		print(stats);
+        // disk-order scan
+        LOGGER.info("DISK-ORDER SCAN:");
+        TreeDiskOrderScanCursor diskOrderCursor = new TreeDiskOrderScanCursor(leafFrame);
+        BTreeOpContext diskOrderScanOpCtx = btree.createOpContext(IndexOp.DISKORDERSCAN, leafFrame, null, null);
+        btree.diskOrderScan(diskOrderCursor, leafFrame, metaFrame, diskOrderScanOpCtx);
+        try {
+            while (diskOrderCursor.hasNext()) {
+                diskOrderCursor.next();
+                ITupleReference frameTuple = diskOrderCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                LOGGER.info(rec);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            diskOrderCursor.close();
+        }
 
-		long end = System.currentTimeMillis();
-		long duration = end - start;
-		print("DURATION: " + duration + "\n");
+        // range search in [-1000, 1000]
+        LOGGER.info("RANGE SEARCH:");
 
-		// ordered scan
+        ITreeIndexCursor rangeCursor = new BTreeRangeSearchCursor(leafFrame);
 
-		print("ORDERED SCAN:\n");
-		IBTreeCursor scanCursor = new RangeSearchCursor(leafFrame);
-		RangePredicate nullPred = new RangePredicate(true, null, null, true,
-				true, null, null);
-		BTreeOpContext searchOpCtx = btree.createOpContext(BTreeOp.BTO_SEARCH,
-				leafFrame, interiorFrame, null);
-		btree.search(scanCursor, nullPred, searchOpCtx);
-		try {
-			while (scanCursor.hasNext()) {
-				scanCursor.next();
-				ITupleReference frameTuple = scanCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			scanCursor.close();
-		}
+        // build low and high keys
+        ArrayTupleBuilder ktb = new ArrayTupleBuilder(cmp.getKeyFieldCount());
+        DataOutput kdos = ktb.getDataOutput();
 
-		// disk-order scan
-		print("DISK-ORDER SCAN:\n");
-		DiskOrderScanCursor diskOrderCursor = new DiskOrderScanCursor(leafFrame);
-		btree.diskOrderScan(diskOrderCursor, leafFrame, metaFrame);
-		try {
-			while (diskOrderCursor.hasNext()) {
-				diskOrderCursor.next();
-				ITupleReference frameTuple = diskOrderCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			diskOrderCursor.close();
-		}
+        ISerializerDeserializer[] keyDescSers = { IntegerSerializerDeserializer.INSTANCE };
+        RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
+        IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx.getFrameSize(), keyDesc);
+        keyAccessor.reset(frame);
 
-		// range search in [-1000, 1000]
-		print("RANGE SEARCH:\n");
+        appender.reset(frame, true);
 
-		IBTreeCursor rangeCursor = new RangeSearchCursor(leafFrame);
+        // build and append low key
+        ktb.reset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(-1000, kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		// build low and high keys
-		ArrayTupleBuilder ktb = new ArrayTupleBuilder(cmp.getKeyFieldCount());
-		DataOutput kdos = ktb.getDataOutput();
+        // build and append high key
+        ktb.reset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(1000, kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		ISerializerDeserializer[] keyDescSers = { IntegerSerializerDeserializer.INSTANCE };
-		RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
-		IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), keyDesc);
-		keyAccessor.reset(frame);
+        // create tuplereferences for search keys
+        FrameTupleReference lowKey = new FrameTupleReference();
+        lowKey.reset(keyAccessor, 0);
 
-		appender.reset(frame, true);
+        FrameTupleReference highKey = new FrameTupleReference();
+        highKey.reset(keyAccessor, 1);
 
-		// build and append low key
-		ktb.reset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(-1000, kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        IBinaryComparator[] searchCmps = new IBinaryComparator[1];
+        searchCmps[0] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps);
 
-		// build and append high key
-		ktb.reset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(1000, kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        RangePredicate rangePred = new RangePredicate(true, lowKey, highKey, true, true, searchCmp, searchCmp);
+        btree.search(rangeCursor, rangePred, searchOpCtx);
 
-		// create tuplereferences for search keys
-		FrameTupleReference lowKey = new FrameTupleReference();
-		lowKey.reset(keyAccessor, 0);
+        try {
+            while (rangeCursor.hasNext()) {
+                rangeCursor.next();
+                ITupleReference frameTuple = rangeCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                LOGGER.info(rec);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            rangeCursor.close();
+        }
 
-		FrameTupleReference highKey = new FrameTupleReference();
-		highKey.reset(keyAccessor, 1);
+        btree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+    }
 
-		IBinaryComparator[] searchCmps = new IBinaryComparator[1];
-		searchCmps[0] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps);
+    // COMPOSITE KEY TEST (NON-UNIQUE B-TREE)
+    // create a B-tree with one two fixed-length "key" fields and one
+    // fixed-length "value" field
+    // fill B-tree with random values using insertions (not bulk load)
+    // perform ordered scan and range search
+    @Test
+    public void test02() throws Exception {
 
-		RangePredicate rangePred = new RangePredicate(true, lowKey, highKey,
-				true, true, searchCmp, searchCmp);
-		btree.search(rangeCursor, rangePred, searchOpCtx);
+        LOGGER.info("COMPOSITE KEY TEST");
 
-		try {
-			while (rangeCursor.hasNext()) {
-				rangeCursor.next();
-				ITupleReference frameTuple = rangeCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			rangeCursor.close();
-		}
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
 
-		btree.close();
-		bufferCache.closeFile(fileId);
-		bufferCache.close();
+        // declare fields
+        int fieldCount = 3;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(4);
+        typeTraits[1] = new TypeTrait(4);
+        typeTraits[2] = new TypeTrait(4);
 
-		print("\n");
-	}
+        // declare keys
+        int keyFieldCount = 2;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        cmps[1] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
 
-	// COMPOSITE KEY TEST (NON-UNIQUE B-TREE)
-	// create a B-tree with one two fixed-length "key" fields and one
-	// fixed-length "value" field
-	// fill B-tree with random values using insertions (not bulk load)
-	// perform ordered scan and range search
-	@Test
-	public void test02() throws Exception {
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
 
-		print("COMPOSITE KEY TEST\n");
+        TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
+        // SimpleTupleWriterFactory tupleWriterFactory = new
+        // SimpleTupleWriterFactory();
+        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
+        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
 
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
-		IBufferCache bufferCache = TestStorageManagerComponentHolder
-				.getBufferCache(ctx);
-		IFileMapProvider fmp = TestStorageManagerComponentHolder
-				.getFileMapProvider(ctx);
-		FileReference file = new FileReference(new File(fileName));
-		bufferCache.createFile(file);
-		int fileId = fmp.lookupFileId(file);
-		bufferCache.openFile(fileId);
+        IBTreeLeafFrame leafFrame = (IBTreeLeafFrame) leafFrameFactory.createFrame();
+        IBTreeInteriorFrame interiorFrame = (IBTreeInteriorFrame) interiorFrameFactory.createFrame();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
 
-		// declare fields
-		int fieldCount = 3;
-		ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
-		typeTraits[0] = new TypeTrait(4);
-		typeTraits[1] = new TypeTrait(4);
-		typeTraits[2] = new TypeTrait(4);
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
 
-		// declare keys
-		int keyFieldCount = 2;
-		IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
-		cmps[0] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		cmps[1] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
+        BTree btree = new BTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        btree.create(fileId, leafFrame, metaFrame);
+        btree.open(fileId);
 
-		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+        Random rnd = new Random();
+        rnd.setSeed(50);
 
-		TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(
-				typeTraits);
-		// SimpleTupleWriterFactory tupleWriterFactory = new
-		// SimpleTupleWriterFactory();
-		IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(
-				tupleWriterFactory);
-		IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(
-				tupleWriterFactory);
-		IBTreeMetaDataFrameFactory metaFrameFactory = new MetaDataFrameFactory();
+        long start = System.currentTimeMillis();
 
-		IBTreeLeafFrame leafFrame = leafFrameFactory.getFrame();
-		IBTreeInteriorFrame interiorFrame = interiorFrameFactory.getFrame();
-		IBTreeMetaDataFrame metaFrame = metaFrameFactory.getFrame();
+        LOGGER.info("INSERTING INTO TREE");
 
-		BTree btree = new BTree(bufferCache, interiorFrameFactory,
-				leafFrameFactory, cmp);
-		btree.create(fileId, leafFrame, metaFrame);
-		btree.open(fileId);
+        ByteBuffer frame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
 
-		Random rnd = new Random();
-		rnd.setSeed(50);
+        ISerializerDeserializer[] recDescSers = { IntegerSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(frame);
+        FrameTupleReference tuple = new FrameTupleReference();
 
-		long start = System.currentTimeMillis();
+        BTreeOpContext insertOpCtx = btree.createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
 
-		print("INSERTING INTO TREE\n");
+        for (int i = 0; i < 10000; i++) {
+            int f0 = rnd.nextInt() % 2000;
+            int f1 = rnd.nextInt() % 1000;
+            int f2 = 5;
 
-		ByteBuffer frame = ctx.allocateFrame();
-		FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
-		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
-		DataOutput dos = tb.getDataOutput();
+            tb.reset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(f0, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(f1, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(f2, dos);
+            tb.addFieldEndOffset();
 
-		ISerializerDeserializer[] recDescSers = {
-				IntegerSerializerDeserializer.INSTANCE,
-				IntegerSerializerDeserializer.INSTANCE,
-				IntegerSerializerDeserializer.INSTANCE };
-		RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
-		IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), recDesc);
-		accessor.reset(frame);
-		FrameTupleReference tuple = new FrameTupleReference();
+            appender.reset(frame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
 
-		BTreeOpContext insertOpCtx = btree.createOpContext(BTreeOp.BTO_INSERT,
-				leafFrame, interiorFrame, metaFrame);
+            tuple.reset(accessor, 0);
 
-		for (int i = 0; i < 10000; i++) {
-			int f0 = rnd.nextInt() % 2000;
-			int f1 = rnd.nextInt() % 1000;
-			int f2 = 5;
+            if (i % 1000 == 0) {
+                LOGGER.info("INSERTING " + i + " : " + f0 + " " + f1);
+            }
 
-			tb.reset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(f0, dos);
-			tb.addFieldEndOffset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(f1, dos);
-			tb.addFieldEndOffset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(f2, dos);
-			tb.addFieldEndOffset();
+            try {
+                btree.insert(tuple, insertOpCtx);
+            } catch (Exception e) {
+            }
+        }
+        // btree.printTree(leafFrame, interiorFrame);
 
-			appender.reset(frame, true);
-			appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb
-					.getSize());
+        long end = System.currentTimeMillis();
+        long duration = end - start;
+        LOGGER.info("DURATION: " + duration);
 
-			tuple.reset(accessor, 0);
+        // try a simple index scan
+        LOGGER.info("ORDERED SCAN:");
+        ITreeIndexCursor scanCursor = new BTreeRangeSearchCursor(leafFrame);
+        RangePredicate nullPred = new RangePredicate(true, null, null, true, true, null, null);
+        BTreeOpContext searchOpCtx = btree.createOpContext(IndexOp.SEARCH, leafFrame, interiorFrame, null);
+        btree.search(scanCursor, nullPred, searchOpCtx);
 
-			if (i % 1000 == 0) {
-				print("INSERTING " + i + " : " + f0 + " " + f1 + "\n");
-			}
+        try {
+            while (scanCursor.hasNext()) {
+                scanCursor.next();
+                ITupleReference frameTuple = scanCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                LOGGER.info(rec);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            scanCursor.close();
+        }
 
-			try {
-				btree.insert(tuple, insertOpCtx);
-			} catch (Exception e) {
-			}
-		}
-		// btree.printTree(leafFrame, interiorFrame);
+        // range search in [(-3),(3)]
+        LOGGER.info("RANGE SEARCH:");
+        ITreeIndexCursor rangeCursor = new BTreeRangeSearchCursor(leafFrame);
 
-		long end = System.currentTimeMillis();
-		long duration = end - start;
-		print("DURATION: " + duration + "\n");
+        // build low and high keys
+        ArrayTupleBuilder ktb = new ArrayTupleBuilder(cmp.getKeyFieldCount());
+        DataOutput kdos = ktb.getDataOutput();
 
-		// try a simple index scan
-		print("ORDERED SCAN:\n");
-		IBTreeCursor scanCursor = new RangeSearchCursor(leafFrame);
-		RangePredicate nullPred = new RangePredicate(true, null, null, true,
-				true, null, null);
-		BTreeOpContext searchOpCtx = btree.createOpContext(BTreeOp.BTO_SEARCH,
-				leafFrame, interiorFrame, null);
-		btree.search(scanCursor, nullPred, searchOpCtx);
+        ISerializerDeserializer[] keyDescSers = { IntegerSerializerDeserializer.INSTANCE };
+        RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
+        IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx.getFrameSize(), keyDesc);
+        keyAccessor.reset(frame);
 
-		try {
-			while (scanCursor.hasNext()) {
-				scanCursor.next();
-				ITupleReference frameTuple = scanCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			scanCursor.close();
-		}
+        appender.reset(frame, true);
 
-		// range search in [(-3),(3)]
-		print("RANGE SEARCH:\n");
-		IBTreeCursor rangeCursor = new RangeSearchCursor(leafFrame);
+        // build and append low key
+        ktb.reset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(-3, kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		// build low and high keys
-		ArrayTupleBuilder ktb = new ArrayTupleBuilder(cmp.getKeyFieldCount());
-		DataOutput kdos = ktb.getDataOutput();
+        // build and append high key
+        ktb.reset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(3, kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		ISerializerDeserializer[] keyDescSers = { IntegerSerializerDeserializer.INSTANCE };
-		RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
-		IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), keyDesc);
-		keyAccessor.reset(frame);
+        // create tuplereferences for search keys
+        FrameTupleReference lowKey = new FrameTupleReference();
+        lowKey.reset(keyAccessor, 0);
 
-		appender.reset(frame, true);
+        FrameTupleReference highKey = new FrameTupleReference();
+        highKey.reset(keyAccessor, 1);
 
-		// build and append low key
-		ktb.reset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(-3, kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        IBinaryComparator[] searchCmps = new IBinaryComparator[1];
+        searchCmps[0] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps); // use
+        // only
+        // a
+        // single
+        // comparator
+        // for
+        // searching
 
-		// build and append high key
-		ktb.reset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(3, kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        RangePredicate rangePred = new RangePredicate(true, lowKey, highKey, true, true, searchCmp, searchCmp);
+        btree.search(rangeCursor, rangePred, searchOpCtx);
 
-		// create tuplereferences for search keys
-		FrameTupleReference lowKey = new FrameTupleReference();
-		lowKey.reset(keyAccessor, 0);
+        try {
+            while (rangeCursor.hasNext()) {
+                rangeCursor.next();
+                ITupleReference frameTuple = rangeCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                print(rec + "\n");
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            rangeCursor.close();
+        }
 
-		FrameTupleReference highKey = new FrameTupleReference();
-		highKey.reset(keyAccessor, 1);
+        btree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+    }
 
-		IBinaryComparator[] searchCmps = new IBinaryComparator[1];
-		searchCmps[0] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps); // use
-		// only
-		// a
-		// single
-		// comparator
-		// for
-		// searching
+    // VARIABLE-LENGTH TEST
+    // create a B-tree with one variable-length "key" field and one
+    // variable-length "value" field
+    // fill B-tree with random values using insertions (not bulk load)
+    // perform ordered scan and range search
+    @Test
+    public void test03() throws Exception {
 
-		RangePredicate rangePred = new RangePredicate(true, lowKey, highKey,
-				true, true, searchCmp, searchCmp);
-		btree.search(rangeCursor, rangePred, searchOpCtx);
+        LOGGER.info("VARIABLE-LENGTH KEY TEST");
 
-		try {
-			while (rangeCursor.hasNext()) {
-				rangeCursor.next();
-				ITupleReference frameTuple = rangeCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			rangeCursor.close();
-		}
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
 
-		btree.close();
-		bufferCache.closeFile(fileId);
-		bufferCache.close();
+        // declare fields
+        int fieldCount = 2;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        typeTraits[1] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
 
-		print("\n");
-	}
+        // declare keys
+        int keyFieldCount = 1;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = UTF8StringBinaryComparatorFactory.INSTANCE.createBinaryComparator();
 
-	// VARIABLE-LENGTH TEST
-	// create a B-tree with one variable-length "key" field and one
-	// variable-length "value" field
-	// fill B-tree with random values using insertions (not bulk load)
-	// perform ordered scan and range search
-	@Test
-	public void test03() throws Exception {
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
 
-		print("VARIABLE-LENGTH KEY TEST\n");
+        SimpleTupleWriterFactory tupleWriterFactory = new SimpleTupleWriterFactory();
+        // TypeAwareTupleWriterFactory tupleWriterFactory = new
+        // TypeAwareTupleWriterFactory(typeTraits);
+        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
+        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
 
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
-		IBufferCache bufferCache = TestStorageManagerComponentHolder
-				.getBufferCache(ctx);
-		IFileMapProvider fmp = TestStorageManagerComponentHolder
-				.getFileMapProvider(ctx);
-		FileReference file = new FileReference(new File(fileName));
-		bufferCache.createFile(file);
-		int fileId = fmp.lookupFileId(file);
-		bufferCache.openFile(fileId);
+        IBTreeLeafFrame leafFrame = (IBTreeLeafFrame) leafFrameFactory.createFrame();
+        IBTreeInteriorFrame interiorFrame = (IBTreeInteriorFrame) interiorFrameFactory.createFrame();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
 
-		// declare fields
-		int fieldCount = 2;
-		ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
-		typeTraits[0] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
-		typeTraits[1] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
 
-		// declare keys
-		int keyFieldCount = 1;
-		IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
-		cmps[0] = UTF8StringBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
+        BTree btree = new BTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        btree.create(fileId, leafFrame, metaFrame);
+        btree.open(fileId);
 
-		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+        Random rnd = new Random();
+        rnd.setSeed(50);
 
-		SimpleTupleWriterFactory tupleWriterFactory = new SimpleTupleWriterFactory();
-		// TypeAwareTupleWriterFactory tupleWriterFactory = new
-		// TypeAwareTupleWriterFactory(typeTraits);
-		IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(
-				tupleWriterFactory);
-		IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(
-				tupleWriterFactory);
-		IBTreeMetaDataFrameFactory metaFrameFactory = new MetaDataFrameFactory();
+        ByteBuffer frame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
 
-		IBTreeLeafFrame leafFrame = leafFrameFactory.getFrame();
-		IBTreeInteriorFrame interiorFrame = interiorFrameFactory.getFrame();
-		IBTreeMetaDataFrame metaFrame = metaFrameFactory.getFrame();
+        ISerializerDeserializer[] recDescSers = { UTF8StringSerializerDeserializer.INSTANCE,
+                UTF8StringSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(frame);
+        FrameTupleReference tuple = new FrameTupleReference();
 
-		BTree btree = new BTree(bufferCache, interiorFrameFactory,
-				leafFrameFactory, cmp);
-		btree.create(fileId, leafFrame, metaFrame);
-		btree.open(fileId);
+        BTreeOpContext insertOpCtx = btree.createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
+        int maxLength = 10; // max string length to be generated
+        for (int i = 0; i < 10000; i++) {
 
-		Random rnd = new Random();
-		rnd.setSeed(50);
+            String f0 = randomString(Math.abs(rnd.nextInt()) % maxLength + 1, rnd);
+            String f1 = randomString(Math.abs(rnd.nextInt()) % maxLength + 1, rnd);
 
-		ByteBuffer frame = ctx.allocateFrame();
-		FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
-		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
-		DataOutput dos = tb.getDataOutput();
+            tb.reset();
+            UTF8StringSerializerDeserializer.INSTANCE.serialize(f0, dos);
+            tb.addFieldEndOffset();
+            UTF8StringSerializerDeserializer.INSTANCE.serialize(f1, dos);
+            tb.addFieldEndOffset();
 
-		ISerializerDeserializer[] recDescSers = {
-				UTF8StringSerializerDeserializer.INSTANCE,
-				UTF8StringSerializerDeserializer.INSTANCE };
-		RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
-		IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), recDesc);
-		accessor.reset(frame);
-		FrameTupleReference tuple = new FrameTupleReference();
+            appender.reset(frame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
 
-		BTreeOpContext insertOpCtx = btree.createOpContext(BTreeOp.BTO_INSERT,
-				leafFrame, interiorFrame, metaFrame);
-		int maxLength = 10; // max string length to be generated
-		for (int i = 0; i < 10000; i++) {
+            tuple.reset(accessor, 0);
 
-			String f0 = randomString(Math.abs(rnd.nextInt()) % maxLength + 1,
-					rnd);
-			String f1 = randomString(Math.abs(rnd.nextInt()) % maxLength + 1,
-					rnd);
+            if (i % 1000 == 0) {
+                LOGGER.info("INSERTING " + i);
+            }
 
-			tb.reset();
-			UTF8StringSerializerDeserializer.INSTANCE.serialize(f0, dos);
-			tb.addFieldEndOffset();
-			UTF8StringSerializerDeserializer.INSTANCE.serialize(f1, dos);
-			tb.addFieldEndOffset();
+            try {
+                btree.insert(tuple, insertOpCtx);
+            } catch (Exception e) {
+            }
+        }
+        // btree.printTree();
 
-			appender.reset(frame, true);
-			appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb
-					.getSize());
+        LOGGER.info("DONE INSERTING");
 
-			tuple.reset(accessor, 0);
+        // ordered scan
+        LOGGER.info("ORDERED SCAN:");
+        ITreeIndexCursor scanCursor = new BTreeRangeSearchCursor(leafFrame);
+        RangePredicate nullPred = new RangePredicate(true, null, null, true, true, null, null);
+        BTreeOpContext searchOpCtx = btree.createOpContext(IndexOp.SEARCH, leafFrame, interiorFrame, null);
+        btree.search(scanCursor, nullPred, searchOpCtx);
 
-			if (i % 1000 == 0) {
-				// print("INSERTING " + i + ": " + cmp.printRecord(record, 0) +
-				// "\n");
-				print("INSERTING " + i + "\n");
-			}
+        try {
+            while (scanCursor.hasNext()) {
+                scanCursor.next();
+                ITupleReference frameTuple = scanCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                LOGGER.info(rec);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            scanCursor.close();
+        }
 
-			try {
-				btree.insert(tuple, insertOpCtx);
-			} catch (Exception e) {
-				// e.printStackTrace();
-			}
-		}
-		// btree.printTree();
+        // range search in ["cbf", cc7"]
+        LOGGER.info("RANGE SEARCH:");
 
-		System.out.println("DONE INSERTING");
+        ITreeIndexCursor rangeCursor = new BTreeRangeSearchCursor(leafFrame);
 
-		// ordered scan
-		print("ORDERED SCAN:\n");
-		IBTreeCursor scanCursor = new RangeSearchCursor(leafFrame);
-		RangePredicate nullPred = new RangePredicate(true, null, null, true,
-				true, null, null);
-		BTreeOpContext searchOpCtx = btree.createOpContext(BTreeOp.BTO_SEARCH,
-				leafFrame, interiorFrame, null);
-		btree.search(scanCursor, nullPred, searchOpCtx);
+        // build low and high keys
+        ArrayTupleBuilder ktb = new ArrayTupleBuilder(cmp.getKeyFieldCount());
+        DataOutput kdos = ktb.getDataOutput();
 
-		try {
-			while (scanCursor.hasNext()) {
-				scanCursor.next();
-				ITupleReference frameTuple = scanCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			scanCursor.close();
-		}
+        ISerializerDeserializer[] keyDescSers = { UTF8StringSerializerDeserializer.INSTANCE };
+        RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
+        IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx.getFrameSize(), keyDesc);
+        keyAccessor.reset(frame);
 
-		// range search in ["cbf", cc7"]
-		print("RANGE SEARCH:\n");
+        appender.reset(frame, true);
 
-		IBTreeCursor rangeCursor = new RangeSearchCursor(leafFrame);
+        // build and append low key
+        ktb.reset();
+        UTF8StringSerializerDeserializer.INSTANCE.serialize("cbf", kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		// build low and high keys
-		ArrayTupleBuilder ktb = new ArrayTupleBuilder(cmp.getKeyFieldCount());
-		DataOutput kdos = ktb.getDataOutput();
+        // build and append high key
+        ktb.reset();
+        UTF8StringSerializerDeserializer.INSTANCE.serialize("cc7", kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		ISerializerDeserializer[] keyDescSers = { UTF8StringSerializerDeserializer.INSTANCE };
-		RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
-		IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), keyDesc);
-		keyAccessor.reset(frame);
+        // create tuplereferences for search keys
+        FrameTupleReference lowKey = new FrameTupleReference();
+        lowKey.reset(keyAccessor, 0);
 
-		appender.reset(frame, true);
+        FrameTupleReference highKey = new FrameTupleReference();
+        highKey.reset(keyAccessor, 1);
 
-		// build and append low key
-		ktb.reset();
-		UTF8StringSerializerDeserializer.INSTANCE.serialize("cbf", kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        IBinaryComparator[] searchCmps = new IBinaryComparator[1];
+        searchCmps[0] = UTF8StringBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps);
 
-		// build and append high key
-		ktb.reset();
-		UTF8StringSerializerDeserializer.INSTANCE.serialize("cc7", kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        RangePredicate rangePred = new RangePredicate(true, lowKey, highKey, true, true, searchCmp, searchCmp);
+        btree.search(rangeCursor, rangePred, searchOpCtx);
 
-		// create tuplereferences for search keys
-		FrameTupleReference lowKey = new FrameTupleReference();
-		lowKey.reset(keyAccessor, 0);
+        try {
+            while (rangeCursor.hasNext()) {
+                rangeCursor.next();
+                ITupleReference frameTuple = rangeCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                LOGGER.info(rec);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            rangeCursor.close();
+        }
 
-		FrameTupleReference highKey = new FrameTupleReference();
-		highKey.reset(keyAccessor, 1);
-
-		IBinaryComparator[] searchCmps = new IBinaryComparator[1];
-		searchCmps[0] = UTF8StringBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps);
-
-		RangePredicate rangePred = new RangePredicate(true, lowKey, highKey,
-				true, true, searchCmp, searchCmp);
-		btree.search(rangeCursor, rangePred, searchOpCtx);
-
-		try {
-			while (rangeCursor.hasNext()) {
-				rangeCursor.next();
-				ITupleReference frameTuple = rangeCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			rangeCursor.close();
-		}
-
-		btree.close();
-		bufferCache.closeFile(fileId);
-		bufferCache.close();
-
-		print("\n");
-	}
-
-	// DELETION TEST
-	// create a B-tree with one variable-length "key" field and one
-	// variable-length "value" field
-	// fill B-tree with random values using insertions, then delete entries
-	// one-by-one
-	// repeat procedure a few times on same B-tree
-	@Test
-	public void test04() throws Exception {
+        btree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+    }
 
-		print("DELETION TEST\n");
+    // DELETION TEST
+    // create a B-tree with one variable-length "key" field and one
+    // variable-length "value" field
+    // fill B-tree with random values using insertions, then delete entries
+    // one-by-one
+    // repeat procedure a few times on same B-tree
+    @Test
+    public void test04() throws Exception {
 
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
-		IBufferCache bufferCache = TestStorageManagerComponentHolder
-				.getBufferCache(ctx);
-		IFileMapProvider fmp = TestStorageManagerComponentHolder
-				.getFileMapProvider(ctx);
-		FileReference file = new FileReference(new File(fileName));
-		bufferCache.createFile(file);
-		int fileId = fmp.lookupFileId(file);
-		bufferCache.openFile(fileId);
+        LOGGER.info("DELETION TEST");
 
-		// declare fields
-		int fieldCount = 2;
-		ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
-		typeTraits[0] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
-		typeTraits[1] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
 
-		// declare keys
-		int keyFieldCount = 1;
-		IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
-		cmps[0] = UTF8StringBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
+        // declare fields
+        int fieldCount = 2;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+        typeTraits[1] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
 
-		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+        // declare keys
+        int keyFieldCount = 1;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = UTF8StringBinaryComparatorFactory.INSTANCE.createBinaryComparator();
 
-		// SimpleTupleWriterFactory tupleWriterFactory = new
-		// SimpleTupleWriterFactory();
-		TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(
-				typeTraits);
-		IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(
-				tupleWriterFactory);
-		IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(
-				tupleWriterFactory);
-		IBTreeMetaDataFrameFactory metaFrameFactory = new MetaDataFrameFactory();
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
 
-		IBTreeLeafFrame leafFrame = leafFrameFactory.getFrame();
-		IBTreeInteriorFrame interiorFrame = interiorFrameFactory.getFrame();
-		IBTreeMetaDataFrame metaFrame = metaFrameFactory.getFrame();
+        // SimpleTupleWriterFactory tupleWriterFactory = new
+        // SimpleTupleWriterFactory();
+        TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
+        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
+        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
 
-		BTree btree = new BTree(bufferCache, interiorFrameFactory,
-				leafFrameFactory, cmp);
-		btree.create(fileId, leafFrame, metaFrame);
-		btree.open(fileId);
+        IBTreeLeafFrame leafFrame = (IBTreeLeafFrame) leafFrameFactory.createFrame();
+        IBTreeInteriorFrame interiorFrame = (IBTreeInteriorFrame) interiorFrameFactory.createFrame();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
 
-		Random rnd = new Random();
-		rnd.setSeed(50);
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
 
-		ByteBuffer frame = ctx.allocateFrame();
-		FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
-		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
-		DataOutput dos = tb.getDataOutput();
+        BTree btree = new BTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        btree.create(fileId, leafFrame, metaFrame);
+        btree.open(fileId);
 
-		ISerializerDeserializer[] recDescSers = {
-				UTF8StringSerializerDeserializer.INSTANCE,
-				UTF8StringSerializerDeserializer.INSTANCE };
-		RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
-		IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), recDesc);
-		accessor.reset(frame);
-		FrameTupleReference tuple = new FrameTupleReference();
+        Random rnd = new Random();
+        rnd.setSeed(50);
 
-		BTreeOpContext insertOpCtx = btree.createOpContext(BTreeOp.BTO_INSERT,
-				leafFrame, interiorFrame, metaFrame);
-		BTreeOpContext deleteOpCtx = btree.createOpContext(BTreeOp.BTO_DELETE,
-				leafFrame, interiorFrame, metaFrame);
+        ByteBuffer frame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
 
-		int runs = 3;
-		for (int run = 0; run < runs; run++) {
+        ISerializerDeserializer[] recDescSers = { UTF8StringSerializerDeserializer.INSTANCE,
+                UTF8StringSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(frame);
+        FrameTupleReference tuple = new FrameTupleReference();
 
-			print("DELETION TEST RUN: " + (run + 1) + "/" + runs + "\n");
+        BTreeOpContext insertOpCtx = btree.createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
+        BTreeOpContext deleteOpCtx = btree.createOpContext(IndexOp.DELETE, leafFrame, interiorFrame, metaFrame);
 
-			print("INSERTING INTO BTREE\n");
-			int maxLength = 10;
-			int ins = 10000;
-			String[] f0s = new String[ins];
-			String[] f1s = new String[ins];
-			int insDone = 0;
-			int[] insDoneCmp = new int[ins];
-			for (int i = 0; i < ins; i++) {
-				String f0 = randomString(Math.abs(rnd.nextInt()) % maxLength
-						+ 1, rnd);
-				String f1 = randomString(Math.abs(rnd.nextInt()) % maxLength
-						+ 1, rnd);
+        int runs = 3;
+        for (int run = 0; run < runs; run++) {
 
-				f0s[i] = f0;
-				f1s[i] = f1;
+            LOGGER.info("DELETION TEST RUN: " + (run + 1) + "/" + runs);
 
-				tb.reset();
-				UTF8StringSerializerDeserializer.INSTANCE.serialize(f0, dos);
-				tb.addFieldEndOffset();
-				UTF8StringSerializerDeserializer.INSTANCE.serialize(f1, dos);
-				tb.addFieldEndOffset();
+            LOGGER.info("INSERTING INTO BTREE");
+            int maxLength = 10;
+            int ins = 10000;
+            String[] f0s = new String[ins];
+            String[] f1s = new String[ins];
+            int insDone = 0;
+            int[] insDoneCmp = new int[ins];
+            for (int i = 0; i < ins; i++) {
+                String f0 = randomString(Math.abs(rnd.nextInt()) % maxLength + 1, rnd);
+                String f1 = randomString(Math.abs(rnd.nextInt()) % maxLength + 1, rnd);
 
-				appender.reset(frame, true);
-				appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0,
-						tb.getSize());
+                f0s[i] = f0;
+                f1s[i] = f1;
 
-				tuple.reset(accessor, 0);
+                tb.reset();
+                UTF8StringSerializerDeserializer.INSTANCE.serialize(f0, dos);
+                tb.addFieldEndOffset();
+                UTF8StringSerializerDeserializer.INSTANCE.serialize(f1, dos);
+                tb.addFieldEndOffset();
 
-				if (i % 1000 == 0) {
-					print("INSERTING " + i + "\n");
-					// print("INSERTING " + i + ": " + cmp.printRecord(record,
-					// 0) + "\n");
-				}
+                appender.reset(frame, true);
+                appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
 
-				try {
-					btree.insert(tuple, insertOpCtx);
-					insDone++;
-				} catch (BTreeException e) {
-					// e.printStackTrace();
-				} catch (Exception e) {
-					e.printStackTrace();
-				}
+                tuple.reset(accessor, 0);
 
-				insDoneCmp[i] = insDone;
-			}
-			// btree.printTree();
-			// btree.printStats();
+                if (i % 1000 == 0) {
+                    LOGGER.info("INSERTING " + i);
+                }
 
-			print("DELETING FROM BTREE\n");
-			int delDone = 0;
-			for (int i = 0; i < ins; i++) {
+                try {
+                    btree.insert(tuple, insertOpCtx);
+                    insDone++;
+                } catch (TreeIndexException e) {
+                    // e.printStackTrace();
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
 
-				tb.reset();
-				UTF8StringSerializerDeserializer.INSTANCE
-						.serialize(f0s[i], dos);
-				tb.addFieldEndOffset();
-				UTF8StringSerializerDeserializer.INSTANCE
-						.serialize(f1s[i], dos);
-				tb.addFieldEndOffset();
+                insDoneCmp[i] = insDone;
+            }
+            // btree.printTree();
+            // btree.printStats();
 
-				appender.reset(frame, true);
-				appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0,
-						tb.getSize());
+            LOGGER.info("DELETING FROM BTREE");
+            int delDone = 0;
+            for (int i = 0; i < ins; i++) {
 
-				tuple.reset(accessor, 0);
+                tb.reset();
+                UTF8StringSerializerDeserializer.INSTANCE.serialize(f0s[i], dos);
+                tb.addFieldEndOffset();
+                UTF8StringSerializerDeserializer.INSTANCE.serialize(f1s[i], dos);
+                tb.addFieldEndOffset();
 
-				if (i % 1000 == 0) {
-					// print("DELETING " + i + ": " +
-					// cmp.printRecord(records[i], 0) + "\n");
-					print("DELETING " + i + "\n");
-				}
+                appender.reset(frame, true);
+                appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
 
-				try {
-					btree.delete(tuple, deleteOpCtx);
-					delDone++;
-				} catch (BTreeException e) {
-					// e.printStackTrace();
-				} catch (Exception e) {
-					e.printStackTrace();
-				}
+                tuple.reset(accessor, 0);
 
-				if (insDoneCmp[i] != delDone) {
-					print("INCONSISTENT STATE, ERROR IN DELETION TEST\n");
-					print("INSDONECMP: " + insDoneCmp[i] + " " + delDone + "\n");
-					break;
-				}
-				// btree.printTree();
-			}
-			// btree.printTree(leafFrame, interiorFrame);
+                if (i % 1000 == 0) {
+                    LOGGER.info("DELETING " + i);
+                }
 
-			if (insDone != delDone) {
-				print("ERROR! INSDONE: " + insDone + " DELDONE: " + delDone);
-				break;
-			}
-		}
+                try {
+                    btree.delete(tuple, deleteOpCtx);
+                    delDone++;
+                } catch (TreeIndexException e) {
+                    // e.printStackTrace();
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
 
-		btree.close();
-		bufferCache.closeFile(fileId);
-		bufferCache.close();
+                if (insDoneCmp[i] != delDone) {
+                    LOGGER.info("INCONSISTENT STATE, ERROR IN DELETION TEST");
+                    LOGGER.info("INSDONECMP: " + insDoneCmp[i] + " " + delDone);
+                    break;
+                }
+            }
+            // btree.printTree(leafFrame, interiorFrame);
 
-		print("\n");
-	}
+            if (insDone != delDone) {
+                LOGGER.info("ERROR! INSDONE: " + insDone + " DELDONE: " + delDone);
+                break;
+            }
+        }
 
-	// BULK LOAD TEST
-	// insert 100,000 records in bulk
-	// B-tree has a composite key to "simulate" non-unique index creation
-	// do range search
-	@Test
-	public void test05() throws Exception {
+        btree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+    }
 
-		print("BULK LOAD TEST\n");
+    // BULK LOAD TEST
+    // insert 100,000 records in bulk
+    // B-tree has a composite key to "simulate" non-unique index creation
+    // do range search
+    @Test
+    public void test05() throws Exception {
 
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
-		IBufferCache bufferCache = TestStorageManagerComponentHolder
-				.getBufferCache(ctx);
-		IFileMapProvider fmp = TestStorageManagerComponentHolder
-				.getFileMapProvider(ctx);
-		FileReference file = new FileReference(new File(fileName));
-		bufferCache.createFile(file);
-		int fileId = fmp.lookupFileId(file);
-		bufferCache.openFile(fileId);
+        LOGGER.info("BULK LOAD TEST");
 
-		// declare fields
-		int fieldCount = 3;
-		ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
-		typeTraits[0] = new TypeTrait(4);
-		typeTraits[1] = new TypeTrait(4);
-		typeTraits[2] = new TypeTrait(4);
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
 
-		// declare keys
-		int keyFieldCount = 2;
-		IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
-		cmps[0] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		cmps[1] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
+        // declare fields
+        int fieldCount = 3;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(4);
+        typeTraits[1] = new TypeTrait(4);
+        typeTraits[2] = new TypeTrait(4);
 
-		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+        // declare keys
+        int keyFieldCount = 2;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        cmps[1] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
 
-		// SimpleTupleWriterFactory tupleWriterFactory = new
-		// SimpleTupleWriterFactory();
-		TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(
-				typeTraits);
-		IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(
-				tupleWriterFactory);
-		IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(
-				tupleWriterFactory);
-		IBTreeMetaDataFrameFactory metaFrameFactory = new MetaDataFrameFactory();
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
 
-		IBTreeLeafFrame leafFrame = leafFrameFactory.getFrame();
-		IBTreeInteriorFrame interiorFrame = interiorFrameFactory.getFrame();
-		IBTreeMetaDataFrame metaFrame = metaFrameFactory.getFrame();
+        // SimpleTupleWriterFactory tupleWriterFactory = new
+        // SimpleTupleWriterFactory();
+        TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
+        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
+        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
 
-		BTree btree = new BTree(bufferCache, interiorFrameFactory,
-				leafFrameFactory, cmp);
-		btree.create(fileId, leafFrame, metaFrame);
-		btree.open(fileId);
+        ITreeIndexFrame leafFrame = leafFrameFactory.createFrame();
+        ITreeIndexFrame interiorFrame = interiorFrameFactory.createFrame();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
 
-		Random rnd = new Random();
-		rnd.setSeed(50);
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
 
-		ByteBuffer frame = ctx.allocateFrame();
-		FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
-		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
-		DataOutput dos = tb.getDataOutput();
+        BTree btree = new BTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        btree.create(fileId, leafFrame, metaFrame);
+        btree.open(fileId);
 
-		ISerializerDeserializer[] recDescSers = {
-				IntegerSerializerDeserializer.INSTANCE,
-				IntegerSerializerDeserializer.INSTANCE,
-				IntegerSerializerDeserializer.INSTANCE };
-		RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
-		IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), recDesc);
-		accessor.reset(frame);
-		FrameTupleReference tuple = new FrameTupleReference();
+        Random rnd = new Random();
+        rnd.setSeed(50);
 
-		BTree.BulkLoadContext bulkLoadCtx = btree.beginBulkLoad(0.7f,
-				leafFrame, interiorFrame, metaFrame);
+        ByteBuffer frame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
 
-		// generate sorted records
-		int ins = 100000;
-		print("BULK LOADING " + ins + " RECORDS\n");
-		long start = System.currentTimeMillis();
-		for (int i = 0; i < ins; i++) {
+        ISerializerDeserializer[] recDescSers = { IntegerSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(frame);
+        FrameTupleReference tuple = new FrameTupleReference();
 
-			tb.reset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(i, dos);
-			tb.addFieldEndOffset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(i, dos);
-			tb.addFieldEndOffset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(5, dos);
-			tb.addFieldEndOffset();
+        IIndexBulkLoadContext bulkLoadCtx = btree.beginBulkLoad(0.7f, leafFrame, interiorFrame, metaFrame);
 
-			appender.reset(frame, true);
-			appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb
-					.getSize());
+        // generate sorted records
+        int ins = 100000;
+        LOGGER.info("BULK LOADING " + ins + " RECORDS");
+        long start = System.currentTimeMillis();
+        for (int i = 0; i < ins; i++) {
 
-			tuple.reset(accessor, 0);
+            tb.reset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(i, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(i, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(5, dos);
+            tb.addFieldEndOffset();
 
-			btree.bulkLoadAddTuple(bulkLoadCtx, tuple);
-		}
+            appender.reset(frame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
 
-		btree.endBulkLoad(bulkLoadCtx);
+            tuple.reset(accessor, 0);
 
-		// btree.printTree(leafFrame, interiorFrame);
+            btree.bulkLoadAddTuple(bulkLoadCtx, tuple);
+        }
 
-		long end = System.currentTimeMillis();
-		long duration = end - start;
-		print("DURATION: " + duration + "\n");
+        btree.endBulkLoad(bulkLoadCtx);
 
-		// range search
-		print("RANGE SEARCH:\n");
-		IBTreeCursor rangeCursor = new RangeSearchCursor(leafFrame);
+        // btree.printTree(leafFrame, interiorFrame);
 
-		// build low and high keys
-		ArrayTupleBuilder ktb = new ArrayTupleBuilder(1);
-		DataOutput kdos = ktb.getDataOutput();
+        long end = System.currentTimeMillis();
+        long duration = end - start;
+        LOGGER.info("DURATION: " + duration);
 
-		ISerializerDeserializer[] keyDescSers = { IntegerSerializerDeserializer.INSTANCE };
-		RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
-		IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), keyDesc);
-		keyAccessor.reset(frame);
+        // range search
+        LOGGER.info("RANGE SEARCH:");
+        ITreeIndexCursor rangeCursor = new BTreeRangeSearchCursor((IBTreeLeafFrame) leafFrame);
 
-		appender.reset(frame, true);
+        // build low and high keys
+        ArrayTupleBuilder ktb = new ArrayTupleBuilder(1);
+        DataOutput kdos = ktb.getDataOutput();
 
-		// build and append low key
-		ktb.reset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(44444, kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        ISerializerDeserializer[] keyDescSers = { IntegerSerializerDeserializer.INSTANCE };
+        RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
+        IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx.getFrameSize(), keyDesc);
+        keyAccessor.reset(frame);
 
-		// build and append high key
-		ktb.reset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(44500, kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        appender.reset(frame, true);
 
-		// create tuplereferences for search keys
-		FrameTupleReference lowKey = new FrameTupleReference();
-		lowKey.reset(keyAccessor, 0);
+        // build and append low key
+        ktb.reset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(44444, kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		FrameTupleReference highKey = new FrameTupleReference();
-		highKey.reset(keyAccessor, 1);
+        // build and append high key
+        ktb.reset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(44500, kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		IBinaryComparator[] searchCmps = new IBinaryComparator[1];
-		searchCmps[0] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps);
+        // create tuplereferences for search keys
+        FrameTupleReference lowKey = new FrameTupleReference();
+        lowKey.reset(keyAccessor, 0);
 
-		// TODO: check when searching backwards
-		RangePredicate rangePred = new RangePredicate(true, lowKey, highKey,
-				true, true, searchCmp, searchCmp);
-		BTreeOpContext searchOpCtx = btree.createOpContext(BTreeOp.BTO_SEARCH,
-				leafFrame, interiorFrame, null);
-		btree.search(rangeCursor, rangePred, searchOpCtx);
+        FrameTupleReference highKey = new FrameTupleReference();
+        highKey.reset(keyAccessor, 1);
 
-		try {
-			while (rangeCursor.hasNext()) {
-				rangeCursor.next();
-				ITupleReference frameTuple = rangeCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			rangeCursor.close();
-		}
+        IBinaryComparator[] searchCmps = new IBinaryComparator[1];
+        searchCmps[0] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps);
 
-		btree.close();
-		bufferCache.closeFile(fileId);
-		bufferCache.close();
+        // TODO: check when searching backwards
+        RangePredicate rangePred = new RangePredicate(true, lowKey, highKey, true, true, searchCmp, searchCmp);
+        BTreeOpContext searchOpCtx = btree.createOpContext(IndexOp.SEARCH, leafFrame, interiorFrame, null);
+        btree.search(rangeCursor, rangePred, searchOpCtx);
 
-		print("\n");
-	}
+        try {
+            while (rangeCursor.hasNext()) {
+                rangeCursor.next();
+                ITupleReference frameTuple = rangeCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                LOGGER.info(rec);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            rangeCursor.close();
+        }
 
-	// TIME-INTERVAL INTERSECTION DEMO FOR EVENT PEOPLE
-	// demo for Arjun to show easy support of intersection queries on
-	// time-intervals
-	@Test
-	public void test06() throws Exception {
+        btree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+    }
 
-		print("TIME-INTERVAL INTERSECTION DEMO\n");
+    // TIME-INTERVAL INTERSECTION DEMO FOR EVENT PEOPLE
+    // demo for Arjun to show easy support of intersection queries on
+    // time-intervals
+    @Test
+    public void test06() throws Exception {
 
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
-		IBufferCache bufferCache = TestStorageManagerComponentHolder
-				.getBufferCache(ctx);
-		IFileMapProvider fmp = TestStorageManagerComponentHolder
-				.getFileMapProvider(ctx);
-		FileReference file = new FileReference(new File(fileName));
-		bufferCache.createFile(file);
-		int fileId = fmp.lookupFileId(file);
-		bufferCache.openFile(fileId);
+        LOGGER.info("TIME-INTERVAL INTERSECTION DEMO");
 
-		// declare fields
-		int fieldCount = 3;
-		ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
-		typeTraits[0] = new TypeTrait(4);
-		typeTraits[1] = new TypeTrait(4);
-		typeTraits[2] = new TypeTrait(4);
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
 
-		// declare keys
-		int keyFieldCount = 2;
-		IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
-		cmps[0] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		cmps[1] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+        // declare fields
+        int fieldCount = 3;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(4);
+        typeTraits[1] = new TypeTrait(4);
+        typeTraits[2] = new TypeTrait(4);
 
-		// SimpleTupleWriterFactory tupleWriterFactory = new
-		// SimpleTupleWriterFactory();
-		TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(
-				typeTraits);
-		IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(
-				tupleWriterFactory);
-		IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(
-				tupleWriterFactory);
-		IBTreeMetaDataFrameFactory metaFrameFactory = new MetaDataFrameFactory();
+        // declare keys
+        int keyFieldCount = 2;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        cmps[1] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
 
-		IBTreeLeafFrame leafFrame = leafFrameFactory.getFrame();
-		IBTreeInteriorFrame interiorFrame = interiorFrameFactory.getFrame();
-		IBTreeMetaDataFrame metaFrame = metaFrameFactory.getFrame();
+        // SimpleTupleWriterFactory tupleWriterFactory = new
+        // SimpleTupleWriterFactory();
+        TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
+        ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(tupleWriterFactory);
+        ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(tupleWriterFactory);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
 
-		BTree btree = new BTree(bufferCache, interiorFrameFactory,
-				leafFrameFactory, cmp);
-		btree.create(fileId, leafFrame, metaFrame);
-		btree.open(fileId);
+        IBTreeLeafFrame leafFrame = (IBTreeLeafFrame) leafFrameFactory.createFrame();
+        IBTreeInteriorFrame interiorFrame = (IBTreeInteriorFrame) interiorFrameFactory.createFrame();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
 
-		Random rnd = new Random();
-		rnd.setSeed(50);
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
 
-		ByteBuffer frame = ctx.allocateFrame();
-		FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
-		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
-		DataOutput dos = tb.getDataOutput();
+        BTree btree = new BTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        btree.create(fileId, leafFrame, metaFrame);
+        btree.open(fileId);
 
-		ISerializerDeserializer[] recDescSers = {
-				IntegerSerializerDeserializer.INSTANCE,
-				IntegerSerializerDeserializer.INSTANCE,
-				IntegerSerializerDeserializer.INSTANCE };
-		RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
-		IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), recDesc);
-		accessor.reset(frame);
-		FrameTupleReference tuple = new FrameTupleReference();
+        Random rnd = new Random();
+        rnd.setSeed(50);
 
-		long start = System.currentTimeMillis();
+        ByteBuffer frame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
 
-		int intervalCount = 10;
-		int[][] intervals = new int[intervalCount][2];
+        ISerializerDeserializer[] recDescSers = { IntegerSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(frame);
+        FrameTupleReference tuple = new FrameTupleReference();
 
-		intervals[0][0] = 10;
-		intervals[0][1] = 20;
+        long start = System.currentTimeMillis();
 
-		intervals[1][0] = 11;
-		intervals[1][1] = 20;
+        int intervalCount = 10;
+        int[][] intervals = new int[intervalCount][2];
 
-		intervals[2][0] = 12;
-		intervals[2][1] = 20;
+        intervals[0][0] = 10;
+        intervals[0][1] = 20;
 
-		intervals[3][0] = 13;
-		intervals[3][1] = 20;
+        intervals[1][0] = 11;
+        intervals[1][1] = 20;
 
-		intervals[4][0] = 14;
-		intervals[4][1] = 20;
+        intervals[2][0] = 12;
+        intervals[2][1] = 20;
 
-		intervals[5][0] = 20;
-		intervals[5][1] = 30;
+        intervals[3][0] = 13;
+        intervals[3][1] = 20;
 
-		intervals[6][0] = 20;
-		intervals[6][1] = 31;
+        intervals[4][0] = 14;
+        intervals[4][1] = 20;
 
-		intervals[7][0] = 20;
-		intervals[7][1] = 32;
+        intervals[5][0] = 20;
+        intervals[5][1] = 30;
 
-		intervals[8][0] = 20;
-		intervals[8][1] = 33;
+        intervals[6][0] = 20;
+        intervals[6][1] = 31;
 
-		intervals[9][0] = 20;
-		intervals[9][1] = 35;
+        intervals[7][0] = 20;
+        intervals[7][1] = 32;
 
-		BTreeOpContext insertOpCtx = btree.createOpContext(BTreeOp.BTO_INSERT,
-				leafFrame, interiorFrame, metaFrame);
+        intervals[8][0] = 20;
+        intervals[8][1] = 33;
 
-		// int exceptionCount = 0;
-		for (int i = 0; i < intervalCount; i++) {
-			int f0 = intervals[i][0];
-			int f1 = intervals[i][1];
-			int f2 = rnd.nextInt() % 100;
+        intervals[9][0] = 20;
+        intervals[9][1] = 35;
 
-			tb.reset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(f0, dos);
-			tb.addFieldEndOffset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(f1, dos);
-			tb.addFieldEndOffset();
-			IntegerSerializerDeserializer.INSTANCE.serialize(f2, dos);
-			tb.addFieldEndOffset();
+        BTreeOpContext insertOpCtx = btree.createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
 
-			appender.reset(frame, true);
-			appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb
-					.getSize());
+        // int exceptionCount = 0;
+        for (int i = 0; i < intervalCount; i++) {
+            int f0 = intervals[i][0];
+            int f1 = intervals[i][1];
+            int f2 = rnd.nextInt() % 100;
 
-			tuple.reset(accessor, 0);
+            tb.reset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(f0, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(f1, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(f2, dos);
+            tb.addFieldEndOffset();
 
-			// print("INSERTING " + i + " : " + f0 + " " + f1 + "\n");
-			print("INSERTING " + i + "\n");
+            appender.reset(frame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
 
-			try {
-				btree.insert(tuple, insertOpCtx);
-			} catch (Exception e) {
-				// e.printStackTrace();
-			}
-		}
-		// btree.printTree(leafFrame, interiorFrame);
-		// btree.printStats();
+            tuple.reset(accessor, 0);
 
-		long end = System.currentTimeMillis();
-		long duration = end - start;
-		print("DURATION: " + duration + "\n");
+            LOGGER.info("INSERTING " + i);
 
-		// try a simple index scan
+            try {
+                btree.insert(tuple, insertOpCtx);
+            } catch (Exception e) {
+            }
+        }
+        // btree.printTree(leafFrame, interiorFrame);
+        // btree.printStats();
 
-		print("ORDERED SCAN:\n");
-		IBTreeCursor scanCursor = new RangeSearchCursor(leafFrame);
-		RangePredicate nullPred = new RangePredicate(true, null, null, true,
-				true, null, null);
-		BTreeOpContext searchOpCtx = btree.createOpContext(BTreeOp.BTO_SEARCH,
-				leafFrame, interiorFrame, null);
-		btree.search(scanCursor, nullPred, searchOpCtx);
+        long end = System.currentTimeMillis();
+        long duration = end - start;
+        LOGGER.info("DURATION: " + duration);
 
-		try {
-			while (scanCursor.hasNext()) {
-				scanCursor.next();
-				ITupleReference frameTuple = scanCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			scanCursor.close();
-		}
+        // try a simple index scan
 
-		// try a range search
-		print("RANGE SEARCH:\n");
-		IBTreeCursor rangeCursor = new RangeSearchCursor(leafFrame);
+        LOGGER.info("ORDERED SCAN:");
+        ITreeIndexCursor scanCursor = new BTreeRangeSearchCursor(leafFrame);
+        RangePredicate nullPred = new RangePredicate(true, null, null, true, true, null, null);
+        BTreeOpContext searchOpCtx = btree.createOpContext(IndexOp.SEARCH, leafFrame, interiorFrame, null);
+        btree.search(scanCursor, nullPred, searchOpCtx);
 
-		// build low and high keys
-		ArrayTupleBuilder ktb = new ArrayTupleBuilder(cmp.getKeyFieldCount());
-		DataOutput kdos = ktb.getDataOutput();
+        try {
+            while (scanCursor.hasNext()) {
+                scanCursor.next();
+                ITupleReference frameTuple = scanCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                print(rec + "\n");
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            scanCursor.close();
+        }
 
-		ISerializerDeserializer[] keyDescSers = {
-				IntegerSerializerDeserializer.INSTANCE,
-				IntegerSerializerDeserializer.INSTANCE };
-		RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
-		IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx
-				.getFrameSize(), keyDesc);
-		keyAccessor.reset(frame);
+        // try a range search
+        LOGGER.info("RANGE SEARCH:");
+        ITreeIndexCursor rangeCursor = new BTreeRangeSearchCursor(leafFrame);
 
-		appender.reset(frame, true);
+        // build low and high keys
+        ArrayTupleBuilder ktb = new ArrayTupleBuilder(cmp.getKeyFieldCount());
+        DataOutput kdos = ktb.getDataOutput();
 
-		// build and append low key
-		ktb.reset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(12, kdos);
-		ktb.addFieldEndOffset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(12, kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        ISerializerDeserializer[] keyDescSers = { IntegerSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE };
+        RecordDescriptor keyDesc = new RecordDescriptor(keyDescSers);
+        IFrameTupleAccessor keyAccessor = new FrameTupleAccessor(ctx.getFrameSize(), keyDesc);
+        keyAccessor.reset(frame);
 
-		// build and append high key
-		ktb.reset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(19, kdos);
-		ktb.addFieldEndOffset();
-		IntegerSerializerDeserializer.INSTANCE.serialize(19, kdos);
-		ktb.addFieldEndOffset();
-		appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb
-				.getSize());
+        appender.reset(frame, true);
 
-		// create tuplereferences for search keys
-		FrameTupleReference lowKey = new FrameTupleReference();
-		lowKey.reset(keyAccessor, 0);
+        // build and append low key
+        ktb.reset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(12, kdos);
+        ktb.addFieldEndOffset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(12, kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		FrameTupleReference highKey = new FrameTupleReference();
-		highKey.reset(keyAccessor, 1);
+        // build and append high key
+        ktb.reset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(19, kdos);
+        ktb.addFieldEndOffset();
+        IntegerSerializerDeserializer.INSTANCE.serialize(19, kdos);
+        ktb.addFieldEndOffset();
+        appender.append(ktb.getFieldEndOffsets(), ktb.getByteArray(), 0, ktb.getSize());
 
-		IBinaryComparator[] searchCmps = new IBinaryComparator[2];
-		searchCmps[0] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		searchCmps[1] = IntegerBinaryComparatorFactory.INSTANCE
-				.createBinaryComparator();
-		MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps);
+        // create tuplereferences for search keys
+        FrameTupleReference lowKey = new FrameTupleReference();
+        lowKey.reset(keyAccessor, 0);
 
-		// print("INDEX RANGE SEARCH ON: " + cmp.printKey(lowKey, 0) + " " +
-		// cmp.printKey(highKey, 0) + "\n");
+        FrameTupleReference highKey = new FrameTupleReference();
+        highKey.reset(keyAccessor, 1);
 
-		RangePredicate rangePred = new RangePredicate(true, lowKey, highKey,
-				true, true, searchCmp, searchCmp);
-		btree.search(rangeCursor, rangePred, searchOpCtx);
+        IBinaryComparator[] searchCmps = new IBinaryComparator[2];
+        searchCmps[0] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        searchCmps[1] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        MultiComparator searchCmp = new MultiComparator(typeTraits, searchCmps);
 
-		try {
-			while (rangeCursor.hasNext()) {
-				rangeCursor.next();
-				ITupleReference frameTuple = rangeCursor.getTuple();
-				String rec = cmp.printTuple(frameTuple, recDescSers);
-				print(rec + "\n");
-			}
-		} catch (Exception e) {
-			e.printStackTrace();
-		} finally {
-			rangeCursor.close();
-		}
+        RangePredicate rangePred = new RangePredicate(true, lowKey, highKey, true, true, searchCmp, searchCmp);
+        btree.search(rangeCursor, rangePred, searchOpCtx);
 
-		btree.close();
-		bufferCache.closeFile(fileId);
-		bufferCache.close();
+        try {
+            while (rangeCursor.hasNext()) {
+                rangeCursor.next();
+                ITupleReference frameTuple = rangeCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                LOGGER.info(rec);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            rangeCursor.close();
+        }
 
-		print("\n");
-	}
+        btree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+    }
 
-	public static String randomString(int length, Random random) {
-		String s = Long.toHexString(Double
-				.doubleToLongBits(random.nextDouble()));
-		StringBuilder strBuilder = new StringBuilder();
-		for (int i = 0; i < s.length() && i < length; i++) {
-			strBuilder
-					.append(s.charAt(Math.abs(random.nextInt()) % s.length()));
-		}
-		return strBuilder.toString();
-	}
+    public static String randomString(int length, Random random) {
+        String s = Long.toHexString(Double.doubleToLongBits(random.nextDouble()));
+        StringBuilder strBuilder = new StringBuilder();
+        for (int i = 0; i < s.length() && i < length; i++) {
+            strBuilder.append(s.charAt(Math.abs(random.nextInt()) % s.length()));
+        }
+        return strBuilder.toString();
+    }
 }
\ No newline at end of file
diff --git a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/RangeSearchCursorTest.java b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/RangeSearchCursorTest.java
index 12371be..1a3b219 100644
--- a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/RangeSearchCursorTest.java
+++ b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/RangeSearchCursorTest.java
@@ -45,27 +45,27 @@
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 import edu.uci.ics.hyracks.dataflow.common.data.comparators.IntegerBinaryComparatorFactory;
 import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeCursor;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
 import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.FieldPrefixNSMLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.MetaDataFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeFieldPrefixNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeException;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
 import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
-import edu.uci.ics.hyracks.storage.am.btree.impls.RangeSearchCursor;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeRangeSearchCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.freepage.LinkedListFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
-import edu.uci.ics.hyracks.storage.common.buffercache.ICacheMemoryAllocator;
 import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
 import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
 import edu.uci.ics.hyracks.test.support.TestUtils;
@@ -73,18 +73,8 @@
 public class RangeSearchCursorTest extends AbstractBTreeTest {
 	private static final int PAGE_SIZE = 256;
 	private static final int NUM_PAGES = 10;
-	private static final int HYRACKS_FRAME_SIZE = 128;
-
-	public class BufferAllocator implements ICacheMemoryAllocator {
-		@Override
-		public ByteBuffer[] allocate(int pageSize, int numPages) {
-			ByteBuffer[] buffers = new ByteBuffer[numPages];
-			for (int i = 0; i < numPages; ++i) {
-				buffers[i] = ByteBuffer.allocate(pageSize);
-			}
-			return buffers;
-		}
-	}
+	private static final int MAX_OPEN_FILES = 10;
+	private static final int HYRACKS_FRAME_SIZE = 128;	
 
 	// declare fields
 	int fieldCount = 2;
@@ -92,15 +82,15 @@
 
 	TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(
 			typeTraits);
-	IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(
+	ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(
 			tupleWriterFactory);
-	IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(
+	ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(
 			tupleWriterFactory);
-	IBTreeMetaDataFrameFactory metaFrameFactory = new MetaDataFrameFactory();
+	ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
 
-	IBTreeLeafFrame leafFrame = leafFrameFactory.getFrame();
-	IBTreeInteriorFrame interiorFrame = interiorFrameFactory.getFrame();
-	IBTreeMetaDataFrame metaFrame = metaFrameFactory.getFrame();
+	IBTreeLeafFrame leafFrame = (IBTreeLeafFrame)leafFrameFactory.createFrame();
+	IBTreeInteriorFrame interiorFrame = (IBTreeInteriorFrame)interiorFrameFactory.createFrame();
+	ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
 
 	IHyracksStageletContext ctx = TestUtils.create(HYRACKS_FRAME_SIZE);
 	ByteBuffer frame = ctx.allocateFrame();
@@ -126,9 +116,9 @@
 	@Test
 	public void uniqueIndexTest() throws Exception {
 
-		System.out.println("TESTING RANGE SEARCH CURSOR ON UNIQUE INDEX");
+	    LOGGER.info("TESTING RANGE SEARCH CURSOR ON UNIQUE INDEX");
 
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
+		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
 		IBufferCache bufferCache = TestStorageManagerComponentHolder
 				.getBufferCache(ctx);
 		IFileMapProvider fmp = TestStorageManagerComponentHolder
@@ -146,7 +136,9 @@
 
 		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
 
-		BTree btree = new BTree(bufferCache, interiorFrameFactory,
+		IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
+		
+		BTree btree = new BTree(bufferCache, freePageManager, interiorFrameFactory,
 				leafFrameFactory, cmp);
 		btree.create(fileId, leafFrame, metaFrame);
 		btree.open(fileId);
@@ -154,7 +146,7 @@
 		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
 		DataOutput dos = tb.getDataOutput();
 
-		BTreeOpContext insertOpCtx = btree.createOpContext(BTreeOp.BTO_INSERT,
+		BTreeOpContext insertOpCtx = btree.createOpContext(IndexOp.INSERT,
 				leafFrame, interiorFrame, metaFrame);
 
 		// generate keys
@@ -199,8 +191,6 @@
 		int minSearchKey = -100;
 		int maxSearchKey = 100;
 
-		// System.out.println("STARTING SEARCH TESTS");
-
 		// forward searches
 		performSearches(keys, btree, leafFrame, interiorFrame, minSearchKey,
 				maxSearchKey, true, true, true, false);
@@ -229,9 +219,9 @@
 	@Test
 	public void nonUniqueIndexTest() throws Exception {
 
-		System.out.println("TESTING RANGE SEARCH CURSOR ON NONUNIQUE INDEX");
+	    LOGGER.info("TESTING RANGE SEARCH CURSOR ON NONUNIQUE INDEX");
 
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
+		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
 		IBufferCache bufferCache = TestStorageManagerComponentHolder
 				.getBufferCache(ctx);
 		IFileMapProvider fmp = TestStorageManagerComponentHolder
@@ -251,7 +241,9 @@
 
 		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
 
-		BTree btree = new BTree(bufferCache, interiorFrameFactory,
+		IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
+		
+		BTree btree = new BTree(bufferCache, freePageManager, interiorFrameFactory,
 				leafFrameFactory, cmp);
 		btree.create(fileId, leafFrame, metaFrame);
 		btree.open(fileId);
@@ -259,7 +251,7 @@
 		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
 		DataOutput dos = tb.getDataOutput();
 
-		BTreeOpContext insertOpCtx = btree.createOpContext(BTreeOp.BTO_INSERT,
+		BTreeOpContext insertOpCtx = btree.createOpContext(IndexOp.INSERT,
 				leafFrame, interiorFrame, metaFrame);
 
 		// generate keys
@@ -301,8 +293,6 @@
 		int minSearchKey = -100;
 		int maxSearchKey = 100;
 
-		// System.out.println("STARTING SEARCH TESTS");
-
 		// forward searches
 		performSearches(keys, btree, leafFrame, interiorFrame, minSearchKey,
 				maxSearchKey, true, true, true, false);
@@ -331,14 +321,13 @@
 	@Test
 	public void nonUniqueFieldPrefixIndexTest() throws Exception {
 
-		System.out
-				.println("TESTING RANGE SEARCH CURSOR ON NONUNIQUE FIELD-PREFIX COMPRESSED INDEX");
+	    LOGGER.info("TESTING RANGE SEARCH CURSOR ON NONUNIQUE FIELD-PREFIX COMPRESSED INDEX");
 
-		IBTreeLeafFrameFactory leafFrameFactory = new FieldPrefixNSMLeafFrameFactory(
+		ITreeIndexFrameFactory leafFrameFactory = new BTreeFieldPrefixNSMLeafFrameFactory(
 				tupleWriterFactory);
-		IBTreeLeafFrame leafFrame = leafFrameFactory.getFrame();
+		IBTreeLeafFrame leafFrame = (IBTreeLeafFrame)leafFrameFactory.createFrame();
 
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
+		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
 		IBufferCache bufferCache = TestStorageManagerComponentHolder
 				.getBufferCache(ctx);
 		IFileMapProvider fmp = TestStorageManagerComponentHolder
@@ -358,7 +347,9 @@
 
 		MultiComparator cmp = new MultiComparator(typeTraits, cmps);
 
-		BTree btree = new BTree(bufferCache, interiorFrameFactory,
+		IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);		
+		
+		BTree btree = new BTree(bufferCache, freePageManager, interiorFrameFactory,
 				leafFrameFactory, cmp);
 		btree.create(fileId, leafFrame, metaFrame);
 		btree.open(fileId);
@@ -366,7 +357,7 @@
 		ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
 		DataOutput dos = tb.getDataOutput();
 
-		BTreeOpContext insertOpCtx = btree.createOpContext(BTreeOp.BTO_INSERT,
+		BTreeOpContext insertOpCtx = btree.createOpContext(IndexOp.INSERT,
 				leafFrame, interiorFrame, metaFrame);
 
 		// generate keys
@@ -408,8 +399,6 @@
 		int minSearchKey = -100;
 		int maxSearchKey = 100;
 
-		// System.out.println("STARTING SEARCH TESTS");
-
 		// forward searches
 		performSearches(keys, btree, leafFrame, interiorFrame, minSearchKey,
 				maxSearchKey, true, true, true, false);
@@ -534,21 +523,19 @@
 		for (int i = minKey; i < maxKey; i++) {
 			for (int j = minKey; j < maxKey; j++) {
 
-				// if(i != -100 || j != 1) continue;
-
 				results.clear();
 				expectedResults.clear();
 
 				int lowKey = i;
 				int highKey = j;
 
-				IBTreeCursor rangeCursor = new RangeSearchCursor(leafFrame);
+				ITreeIndexCursor rangeCursor = new BTreeRangeSearchCursor(leafFrame);
 				RangePredicate rangePred = createRangePredicate(lowKey,
 						highKey, isForward, lowKeyInclusive, highKeyInclusive,
 						btree.getMultiComparator(), btree.getMultiComparator()
 								.getTypeTraits());
 				BTreeOpContext searchOpCtx = btree.createOpContext(
-						BTreeOp.BTO_SEARCH, leafFrame, interiorFrame, null);
+						IndexOp.SEARCH, leafFrame, interiorFrame, null);
 				btree.search(rangeCursor, rangePred, searchOpCtx);
 
 				try {
@@ -587,29 +574,31 @@
 						else
 							u = ')';
 
-						System.out.println("RANGE: " + l + " " + lowKey + " , "
+						LOGGER.info("RANGE: " + l + " " + lowKey + " , "
 								+ highKey + " " + u);
-						for (Integer r : expectedResults)
-							System.out.print(r + " ");
-						System.out.println();
+						StringBuilder strBuilder = new StringBuilder();
+						for (Integer r : expectedResults) {
+							strBuilder.append(r + " ");
+						}
+						LOGGER.info(strBuilder.toString());
 					}
 				}
 
 				if (results.size() == expectedResults.size()) {
 					for (int k = 0; k < results.size(); k++) {
 						if (!results.get(k).equals(expectedResults.get(k))) {
-							System.out.println("DIFFERENT RESULTS AT: i=" + i
+						    LOGGER.info("DIFFERENT RESULTS AT: i=" + i
 									+ " j=" + j + " k=" + k);
-							System.out.println(results.get(k) + " "
+						    LOGGER.info(results.get(k) + " "
 									+ expectedResults.get(k));
 							return false;
 						}
 					}
 				} else {
-					System.out.println("UNEQUAL NUMBER OF RESULTS AT: i=" + i
+				    LOGGER.info("UNEQUAL NUMBER OF RESULTS AT: i=" + i
 							+ " j=" + j);
-					System.out.println("RESULTS: " + results.size());
-					System.out.println("EXPECTED RESULTS: "
+				    LOGGER.info("RESULTS: " + results.size());
+				    LOGGER.info("EXPECTED RESULTS: "
 							+ expectedResults.size());
 					return false;
 				}
diff --git a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/StorageManagerTest.java b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/StorageManagerTest.java
index 430a33c..1a510e6 100644
--- a/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/StorageManagerTest.java
+++ b/hyracks-tests/hyracks-storage-am-btree-test/src/test/java/edu/uci/ics/hyracks/storage/am/btree/StorageManagerTest.java
@@ -25,6 +25,7 @@
 import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
 import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
 import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.storage.am.btree.AbstractBTreeTest;
 import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
 import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
 import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
@@ -36,6 +37,8 @@
 public class StorageManagerTest extends AbstractBTreeTest {
 	private static final int PAGE_SIZE = 256;
 	private static final int NUM_PAGES = 10;
+	private static final int MAX_OPEN_FILES = 10;
+	private static final int HYRACKS_FRAME_SIZE = 128;
 	private IHyracksStageletContext ctx = TestUtils.create(32768);
 
 	public class PinnedLatchedPage {
@@ -87,7 +90,7 @@
 		private void pinRandomPage() {
 			int pageId = Math.abs(rnd.nextInt() % maxPages);
 
-			System.out.println(workerId + " PINNING PAGE: " + pageId);
+			LOGGER.info(workerId + " PINNING PAGE: " + pageId);
 
 			try {
 				ICachedPage page = bufferCache.pin(BufferedFileHandle
@@ -102,14 +105,14 @@
 					break;
 
 				case FTA_READONLY: {
-					System.out.println(workerId + " S LATCHING: " + pageId);
+				    LOGGER.info(workerId + " S LATCHING: " + pageId);
 					page.acquireReadLatch();
 					latch = LatchType.LATCH_S;
 				}
 					break;
 
 				case FTA_WRITEONLY: {
-					System.out.println(workerId + " X LATCHING: " + pageId);
+				    LOGGER.info(workerId + " X LATCHING: " + pageId);
 					page.acquireWriteLatch();
 					latch = LatchType.LATCH_X;
 				}
@@ -117,11 +120,11 @@
 
 				case FTA_MIXED: {
 					if (rnd.nextInt() % 2 == 0) {
-						System.out.println(workerId + " S LATCHING: " + pageId);
+					    LOGGER.info(workerId + " S LATCHING: " + pageId);
 						page.acquireReadLatch();
 						latch = LatchType.LATCH_S;
 					} else {
-						System.out.println(workerId + " X LATCHING: " + pageId);
+					    LOGGER.info(workerId + " X LATCHING: " + pageId);
 						page.acquireWriteLatch();
 						latch = LatchType.LATCH_X;
 					}
@@ -145,16 +148,16 @@
 
 				if (plPage.latch != null) {
 					if (plPage.latch == LatchType.LATCH_S) {
-						System.out.println(workerId + " S UNLATCHING: "
+					    LOGGER.info(workerId + " S UNLATCHING: "
 								+ plPage.pageId);
 						plPage.page.releaseReadLatch();
 					} else {
-						System.out.println(workerId + " X UNLATCHING: "
+					    LOGGER.info(workerId + " X UNLATCHING: "
 								+ plPage.pageId);
 						plPage.page.releaseWriteLatch();
 					}
 				}
-				System.out.println(workerId + " UNPINNING PAGE: "
+				LOGGER.info(workerId + " UNPINNING PAGE: "
 						+ plPage.pageId);
 
 				bufferCache.unpin(plPage.page);
@@ -165,7 +168,7 @@
 		}
 
 		private void openFile() {
-			System.out.println(workerId + " OPENING FILE: " + fileId);
+		    LOGGER.info(workerId + " OPENING FILE: " + fileId);
 			try {
 				bufferCache.openFile(fileId);
 				fileIsOpen = true;
@@ -175,7 +178,7 @@
 		}
 
 		private void closeFile() {
-			System.out.println(workerId + " CLOSING FILE: " + fileId);
+		    LOGGER.info(workerId + " CLOSING FILE: " + fileId);
 			try {
 				bufferCache.closeFile(fileId);
 				fileIsOpen = false;
@@ -192,7 +195,7 @@
 			while (loopCount < maxLoopCount) {
 				loopCount++;
 
-				System.out.println(workerId + " LOOP: " + loopCount + "/"
+				LOGGER.info(workerId + " LOOP: " + loopCount + "/"
 						+ maxLoopCount);
 
 				if (fileIsOpen) {
@@ -247,7 +250,7 @@
 
 	@Test
 	public void oneThreadOneFileTest() throws Exception {
-		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
+		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
 		IBufferCache bufferCache = TestStorageManagerComponentHolder
 				.getBufferCache(ctx);
 		IFileMapProvider fmp = TestStorageManagerComponentHolder
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/.settings/org.eclipse.jdt.core.prefs b/hyracks-tests/hyracks-storage-am-invertedindex-test/.settings/org.eclipse.jdt.core.prefs
index 3cd389e..375e12e 100644
--- a/hyracks-tests/hyracks-storage-am-invertedindex-test/.settings/org.eclipse.jdt.core.prefs
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/.settings/org.eclipse.jdt.core.prefs
@@ -1,4 +1,4 @@
-#Thu Jan 06 11:27:16 PST 2011
+#Fri May 20 19:34:07 PDT 2011
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
 org.eclipse.jdt.core.compiler.compliance=1.6
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexSearchTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexSearchTest.java
new file mode 100644
index 0000000..b42001d
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexSearchTest.java
@@ -0,0 +1,224 @@
+package edu.uci.ics.hyracks.storage.am.invertedindex;
+
+import java.io.DataOutput;
+import java.io.File;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Random;
+
+import org.junit.After;
+import org.junit.Before;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.dataflow.value.TypeTrait;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.FrameTupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.IntegerBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.UTF8StringBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.freepage.LinkedListFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexResultCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.TOccurrenceSearcher;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IBinaryTokenizer;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.ITokenFactory;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
+import edu.uci.ics.hyracks.test.support.TestUtils;
+
+public abstract class AbstractInvIndexSearchTest extends AbstractInvIndexTest {
+	protected final int PAGE_SIZE = 32768;
+	protected final int NUM_PAGES = 100;
+	protected final int MAX_OPEN_FILES = 10;
+	protected final int HYRACKS_FRAME_SIZE = 32768;
+	protected IHyracksStageletContext stageletCtx = TestUtils
+			.create(HYRACKS_FRAME_SIZE);
+
+	protected IBufferCache bufferCache;
+	protected IFileMapProvider fmp;
+
+	// --- BTREE ---
+
+	// create file refs
+	protected FileReference btreeFile = new FileReference(new File(
+			btreeFileName));
+	protected int btreeFileId;
+
+	// declare btree fields
+	protected int fieldCount = 5;
+	protected ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+
+	// declare btree keys
+	protected int btreeKeyFieldCount = 1;
+	protected IBinaryComparator[] btreeBinCmps = new IBinaryComparator[btreeKeyFieldCount];
+	protected MultiComparator btreeCmp = new MultiComparator(typeTraits,
+			btreeBinCmps);
+
+	// btree frame factories
+	protected TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(
+			typeTraits);
+	protected ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(
+			tupleWriterFactory);
+	protected ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(
+			tupleWriterFactory);
+	protected ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
+
+	// btree frames
+	protected ITreeIndexFrame leafFrame = leafFrameFactory.createFrame();
+	protected ITreeIndexMetaDataFrame metaFrame = metaFrameFactory
+			.createFrame();
+
+	protected IFreePageManager freePageManager;
+
+	protected BTree btree;
+
+	// --- INVERTED INDEX ---
+
+	protected FileReference invListsFile = new FileReference(new File(
+			invListsFileName));
+	protected int invListsFileId;
+
+	protected int invListFields = 1;
+	protected ITypeTrait[] invListTypeTraits = new ITypeTrait[invListFields];
+
+	protected int invListKeys = 1;
+	protected IBinaryComparator[] invListBinCmps = new IBinaryComparator[invListKeys];
+	protected MultiComparator invListCmp = new MultiComparator(
+			invListTypeTraits, invListBinCmps);
+
+	protected InvertedIndex invIndex;
+
+	protected Random rnd = new Random();
+
+	protected ByteBuffer frame = stageletCtx.allocateFrame();
+	protected FrameTupleAppender appender = new FrameTupleAppender(
+			stageletCtx.getFrameSize());
+	protected ArrayTupleBuilder tb = new ArrayTupleBuilder(2);
+	protected DataOutput dos = tb.getDataOutput();
+
+	protected ISerializerDeserializer[] insertSerde = {
+			UTF8StringSerializerDeserializer.INSTANCE,
+			IntegerSerializerDeserializer.INSTANCE };
+	protected RecordDescriptor insertRecDesc = new RecordDescriptor(insertSerde);
+	protected IFrameTupleAccessor accessor = new FrameTupleAccessor(
+			stageletCtx.getFrameSize(), insertRecDesc);
+
+	protected FrameTupleReference tuple = new FrameTupleReference();
+
+	protected ArrayList<ArrayList<Integer>> checkInvLists = new ArrayList<ArrayList<Integer>>();
+
+	protected int maxId = 1000000;
+	// protected int maxId = 1000;
+	protected int[] scanCountArray = new int[maxId];
+	protected ArrayList<Integer> expectedResults = new ArrayList<Integer>();
+
+	protected ISerializerDeserializer[] querySerde = { UTF8StringSerializerDeserializer.INSTANCE };
+	protected RecordDescriptor queryRecDesc = new RecordDescriptor(querySerde);
+
+	protected FrameTupleAppender queryAppender = new FrameTupleAppender(
+			stageletCtx.getFrameSize());
+	protected ArrayTupleBuilder queryTb = new ArrayTupleBuilder(
+			querySerde.length);
+	protected DataOutput queryDos = queryTb.getDataOutput();
+
+	protected IFrameTupleAccessor queryAccessor = new FrameTupleAccessor(
+			stageletCtx.getFrameSize(), queryRecDesc);
+	protected FrameTupleReference queryTuple = new FrameTupleReference();
+
+	protected ITokenFactory tokenFactory;
+	protected IBinaryTokenizer tokenizer;
+
+	protected TOccurrenceSearcher searcher;
+	protected IInvertedIndexResultCursor resultCursor;
+
+	/**
+	 * Initialize members, generate data, and bulk load the inverted index.
+	 * 
+	 */
+	@Before
+	public void start() throws Exception {
+		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES,
+				MAX_OPEN_FILES);
+		bufferCache = TestStorageManagerComponentHolder
+				.getBufferCache(stageletCtx);
+		fmp = TestStorageManagerComponentHolder.getFileMapProvider(stageletCtx);
+
+		// --- BTREE ---
+
+		bufferCache.createFile(btreeFile);
+		btreeFileId = fmp.lookupFileId(btreeFile);
+		bufferCache.openFile(btreeFileId);
+
+		// token (key)
+		typeTraits[0] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+		// startPageId
+		typeTraits[1] = new TypeTrait(4);
+		// endPageId
+		typeTraits[2] = new TypeTrait(4);
+		// startOff
+		typeTraits[3] = new TypeTrait(4);
+		// numElements
+		typeTraits[4] = new TypeTrait(4);
+
+		btreeBinCmps[0] = UTF8StringBinaryComparatorFactory.INSTANCE
+				.createBinaryComparator();
+
+		freePageManager = new LinkedListFreePageManager(bufferCache,
+				btreeFileId, 0, metaFrameFactory);
+
+		btree = new BTree(bufferCache, freePageManager, interiorFrameFactory,
+				leafFrameFactory, btreeCmp);
+		btree.create(btreeFileId, leafFrame, metaFrame);
+		btree.open(btreeFileId);
+
+		// --- INVERTED INDEX ---
+
+		bufferCache.createFile(invListsFile);
+		invListsFileId = fmp.lookupFileId(invListsFile);
+		bufferCache.openFile(invListsFileId);
+
+		invListTypeTraits[0] = new TypeTrait(4);
+		invListBinCmps[0] = IntegerBinaryComparatorFactory.INSTANCE
+				.createBinaryComparator();
+
+		invIndex = new InvertedIndex(bufferCache, btree, invListCmp);
+		invIndex.open(invListsFileId);
+
+		rnd.setSeed(50);
+
+		accessor.reset(frame);
+		queryAccessor.reset(frame);
+	}
+
+	@After
+	public void deinit() throws HyracksDataException {
+		AbstractInvIndexTest.tearDown();
+		btree.close();
+		invIndex.close();
+		bufferCache.closeFile(btreeFileId);
+		bufferCache.closeFile(invListsFileId);
+		bufferCache.close();
+	}
+}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexTest.java
new file mode 100644
index 0000000..cc8ab15
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/AbstractInvIndexTest.java
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex;
+
+import java.io.File;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.logging.Logger;
+
+public abstract class AbstractInvIndexTest {
+
+	protected static final Logger LOGGER = Logger
+			.getLogger(AbstractInvIndexTest.class.getName());
+
+	protected final static SimpleDateFormat simpleDateFormat = new SimpleDateFormat(
+			"ddMMyy-hhmmssSS");
+	protected final static String tmpDir = System.getProperty("java.io.tmpdir");
+	protected final static String sep = System.getProperty("file.separator");
+	protected final static String baseFileName = tmpDir + sep
+			+ simpleDateFormat.format(new Date());
+	protected final static String btreeFileName = baseFileName + "btree";
+	protected final static String invListsFileName = baseFileName + "invlists";
+
+	public static void tearDown() {
+		File btreeFile = new File(btreeFileName);
+		btreeFile.deleteOnExit();
+		File invListsFile = new File(invListsFileName);
+		invListsFile.deleteOnExit();
+	}
+}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/BulkLoadTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/BulkLoadTest.java
new file mode 100644
index 0000000..fb0b7b9
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/BulkLoadTest.java
@@ -0,0 +1,345 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex;
+
+import java.io.DataOutput;
+import java.io.File;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Random;
+
+import junit.framework.Assert;
+
+import org.junit.AfterClass;
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.dataflow.value.TypeTrait;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.FrameTupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.IntegerBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.UTF8StringBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.frames.BTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeRangeSearchCursor;
+import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.freepage.LinkedListFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.tuples.TypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.FixedSizeElementInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.FixedSizeElementInvertedListCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
+import edu.uci.ics.hyracks.test.support.TestUtils;
+
+public class BulkLoadTest extends AbstractInvIndexTest {
+
+	private static final int PAGE_SIZE = 32768;
+	private static final int NUM_PAGES = 100;
+	private static final int MAX_OPEN_FILES = 10;
+	private static final int HYRACKS_FRAME_SIZE = 32768;
+	private IHyracksStageletContext stageletCtx = TestUtils
+			.create(HYRACKS_FRAME_SIZE);
+
+	/**
+	 * This test generates a list of <word-token, id> pairs which are pre-sorted
+	 * on the token. Those pairs for the input to an inverted-index bulk load.
+	 * The contents of the inverted lists are verified against the generated
+	 * data.
+	 * 
+	 */
+	@Test
+	public void singleFieldPayloadTest() throws Exception {
+
+		TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES,
+				MAX_OPEN_FILES);
+		IBufferCache bufferCache = TestStorageManagerComponentHolder
+				.getBufferCache(stageletCtx);
+		IFileMapProvider fmp = TestStorageManagerComponentHolder
+				.getFileMapProvider(stageletCtx);
+
+		// create file refs
+		FileReference btreeFile = new FileReference(new File(btreeFileName));
+		bufferCache.createFile(btreeFile);
+		int btreeFileId = fmp.lookupFileId(btreeFile);
+		bufferCache.openFile(btreeFileId);
+
+		FileReference invListsFile = new FileReference(new File(
+				invListsFileName));
+		bufferCache.createFile(invListsFile);
+		int invListsFileId = fmp.lookupFileId(invListsFile);
+		bufferCache.openFile(invListsFileId);
+
+		// declare btree fields
+		int fieldCount = 5;
+		ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+		// token (key)
+		typeTraits[0] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
+		// startPageId
+		typeTraits[1] = new TypeTrait(4);
+		// endPageId
+		typeTraits[2] = new TypeTrait(4);
+		// startOff
+		typeTraits[3] = new TypeTrait(4);
+		// numElements
+		typeTraits[4] = new TypeTrait(4);
+
+		// declare btree keys
+		int keyFieldCount = 1;
+		IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+		cmps[0] = UTF8StringBinaryComparatorFactory.INSTANCE
+				.createBinaryComparator();
+
+		MultiComparator btreeCmp = new MultiComparator(typeTraits, cmps);
+
+		TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(
+				typeTraits);
+		ITreeIndexFrameFactory leafFrameFactory = new BTreeNSMLeafFrameFactory(
+				tupleWriterFactory);
+		ITreeIndexFrameFactory interiorFrameFactory = new BTreeNSMInteriorFrameFactory(
+				tupleWriterFactory);
+		ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
+
+		ITreeIndexFrame leafFrame = leafFrameFactory.createFrame();
+		ITreeIndexFrame interiorFrame = interiorFrameFactory.createFrame();
+		ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
+
+		IFreePageManager freePageManager = new LinkedListFreePageManager(
+				bufferCache, btreeFileId, 0, metaFrameFactory);
+
+		BTree btree = new BTree(bufferCache, freePageManager,
+				interiorFrameFactory, leafFrameFactory, btreeCmp);
+		btree.create(btreeFileId, leafFrame, metaFrame);
+		btree.open(btreeFileId);
+
+		int invListFields = 1;
+		ITypeTrait[] invListTypeTraits = new ITypeTrait[invListFields];
+		invListTypeTraits[0] = new TypeTrait(4);
+
+		int invListKeys = 1;
+		IBinaryComparator[] invListBinCmps = new IBinaryComparator[invListKeys];
+		invListBinCmps[0] = IntegerBinaryComparatorFactory.INSTANCE
+				.createBinaryComparator();
+
+		MultiComparator invListCmp = new MultiComparator(invListTypeTraits,
+				invListBinCmps);
+
+		InvertedIndex invIndex = new InvertedIndex(bufferCache, btree,
+				invListCmp);
+		invIndex.open(invListsFileId);
+
+		Random rnd = new Random();
+		rnd.setSeed(50);
+
+		ByteBuffer frame = stageletCtx.allocateFrame();
+		FrameTupleAppender appender = new FrameTupleAppender(
+				stageletCtx.getFrameSize());
+		ArrayTupleBuilder tb = new ArrayTupleBuilder(2);
+		DataOutput dos = tb.getDataOutput();
+
+		ISerializerDeserializer[] insertSerde = {
+				UTF8StringSerializerDeserializer.INSTANCE,
+				IntegerSerializerDeserializer.INSTANCE };
+		RecordDescriptor insertRecDesc = new RecordDescriptor(insertSerde);
+		IFrameTupleAccessor accessor = new FrameTupleAccessor(
+				stageletCtx.getFrameSize(), insertRecDesc);
+		accessor.reset(frame);
+		FrameTupleReference tuple = new FrameTupleReference();
+
+		List<String> tokens = new ArrayList<String>();
+		tokens.add("compilers");
+		tokens.add("computer");
+		tokens.add("databases");
+		tokens.add("fast");
+		tokens.add("hyracks");
+		tokens.add("major");
+		tokens.add("science");
+		tokens.add("systems");
+		tokens.add("university");
+
+		ArrayList<ArrayList<Integer>> checkListElements = new ArrayList<ArrayList<Integer>>();
+		for (int i = 0; i < tokens.size(); i++) {
+			checkListElements.add(new ArrayList<Integer>());
+		}
+
+		int maxId = 1000000;
+		int addProb = 0;
+		int addProbStep = 10;
+
+		IInvertedListBuilder invListBuilder = new FixedSizeElementInvertedListBuilder(
+				invListTypeTraits);
+		InvertedIndex.BulkLoadContext ctx = invIndex.beginBulkLoad(
+				invListBuilder, HYRACKS_FRAME_SIZE, BTree.DEFAULT_FILL_FACTOR);
+
+		int totalElements = 0;
+		for (int i = 0; i < tokens.size(); i++) {
+
+			addProb += addProbStep * (i + 1);
+			for (int j = 0; j < maxId; j++) {
+				if ((Math.abs(rnd.nextInt()) % addProb) == 0) {
+
+					totalElements++;
+
+					tb.reset();
+					UTF8StringSerializerDeserializer.INSTANCE.serialize(
+							tokens.get(i), dos);
+					tb.addFieldEndOffset();
+					IntegerSerializerDeserializer.INSTANCE.serialize(j, dos);
+					tb.addFieldEndOffset();
+
+					checkListElements.get(i).add(j);
+
+					appender.reset(frame, true);
+					appender.append(tb.getFieldEndOffsets(), tb.getByteArray(),
+							0, tb.getSize());
+
+					tuple.reset(accessor, 0);
+
+					try {
+						invIndex.bulkLoadAddTuple(ctx, tuple);
+					} catch (Exception e) {
+						e.printStackTrace();
+					}
+				}
+			}
+		}
+		invIndex.endBulkLoad(ctx);
+
+		// ------- START VERIFICATION -----------
+
+		ITreeIndexCursor btreeCursor = new BTreeRangeSearchCursor(
+				(IBTreeLeafFrame) leafFrame);
+		FrameTupleReference searchKey = new FrameTupleReference();
+		RangePredicate btreePred = new RangePredicate(true, searchKey,
+				searchKey, true, true, btreeCmp, btreeCmp);
+
+		IInvertedListCursor invListCursor = new FixedSizeElementInvertedListCursor(
+				bufferCache, invListsFileId, invListTypeTraits);
+
+		ISerializerDeserializer[] tokenSerde = { UTF8StringSerializerDeserializer.INSTANCE };
+		RecordDescriptor tokenRecDesc = new RecordDescriptor(tokenSerde);
+		FrameTupleAppender tokenAppender = new FrameTupleAppender(
+				stageletCtx.getFrameSize());
+		ArrayTupleBuilder tokenTupleBuilder = new ArrayTupleBuilder(1);
+		DataOutput tokenDos = tokenTupleBuilder.getDataOutput();
+		IFrameTupleAccessor tokenAccessor = new FrameTupleAccessor(
+				stageletCtx.getFrameSize(), tokenRecDesc);
+		tokenAccessor.reset(frame);
+
+		BTreeOpContext btreeOpCtx = invIndex.getBTree().createOpContext(
+				IndexOp.SEARCH, leafFrame, interiorFrame, null);
+
+		// verify created inverted lists one-by-one
+		for (int i = 0; i < tokens.size(); i++) {
+
+			tokenTupleBuilder.reset();
+			UTF8StringSerializerDeserializer.INSTANCE.serialize(tokens.get(i),
+					tokenDos);
+			tokenTupleBuilder.addFieldEndOffset();
+
+			tokenAppender.reset(frame, true);
+			tokenAppender.append(tokenTupleBuilder.getFieldEndOffsets(),
+					tokenTupleBuilder.getByteArray(), 0,
+					tokenTupleBuilder.getSize());
+
+			searchKey.reset(tokenAccessor, 0);
+
+			invIndex.openCursor(btreeCursor, btreePred, btreeOpCtx,
+					invListCursor);
+
+			invListCursor.pinPagesSync();
+			int checkIndex = 0;
+			while (invListCursor.hasNext()) {
+				invListCursor.next();
+				ITupleReference invListTuple = invListCursor.getTuple();
+				int invListElement = IntegerSerializerDeserializer.getInt(
+						invListTuple.getFieldData(0),
+						invListTuple.getFieldStart(0));
+				int checkInvListElement = checkListElements.get(i)
+						.get(checkIndex).intValue();
+				Assert.assertEquals(invListElement, checkInvListElement);
+				checkIndex++;
+			}
+			invListCursor.unpinPages();
+			Assert.assertEquals(checkIndex, checkListElements.get(i).size());
+		}
+
+		// check that non-existing tokens have an empty inverted list
+		List<String> nonExistingTokens = new ArrayList<String>();
+		nonExistingTokens.add("watermelon");
+		nonExistingTokens.add("avocado");
+		nonExistingTokens.add("lemon");
+
+		for (int i = 0; i < nonExistingTokens.size(); i++) {
+
+			tokenTupleBuilder.reset();
+			UTF8StringSerializerDeserializer.INSTANCE.serialize(
+					nonExistingTokens.get(i), tokenDos);
+			tokenTupleBuilder.addFieldEndOffset();
+
+			tokenAppender.reset(frame, true);
+			tokenAppender.append(tokenTupleBuilder.getFieldEndOffsets(),
+					tokenTupleBuilder.getByteArray(), 0,
+					tokenTupleBuilder.getSize());
+
+			searchKey.reset(tokenAccessor, 0);
+
+			invIndex.openCursor(btreeCursor, btreePred, btreeOpCtx,
+					invListCursor);
+
+			invListCursor.pinPagesSync();
+			Assert.assertEquals(invListCursor.hasNext(), false);
+			invListCursor.unpinPages();
+		}
+
+		btree.close();
+		bufferCache.closeFile(btreeFileId);
+		bufferCache.closeFile(invListsFileId);
+		bufferCache.close();
+	}
+
+	@AfterClass
+	public static void deinit() {
+		AbstractInvIndexTest.tearDown();
+	}
+}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/FixedSizeFrameTupleTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/FixedSizeFrameTupleTest.java
new file mode 100644
index 0000000..0b49ec1
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/FixedSizeFrameTupleTest.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex;
+
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Random;
+
+import junit.framework.Assert;
+
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.TypeTrait;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.FixedSizeFrameTupleAccessor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.FixedSizeFrameTupleAppender;
+
+public class FixedSizeFrameTupleTest {
+
+	private static int FRAME_SIZE = 4096;
+
+	private Random rnd = new Random(50);
+
+	/**
+	 * This test verifies the correct behavior of the FixedSizeFrameTuple class.
+	 * Frames containing FixedSizeFrameTuple's require neither tuple slots nor
+	 * field slots. The tests inserts generated data into a frame until the
+	 * frame is full, and then verifies the frame's contents.
+	 * 
+	 */
+	@Test
+	public void singleFieldTest() throws Exception {
+		ByteBuffer buffer = ByteBuffer.allocate(FRAME_SIZE);
+
+		ITypeTrait[] fields = new TypeTrait[1];
+		fields[0] = new TypeTrait(4);
+
+		FixedSizeFrameTupleAppender ftapp = new FixedSizeFrameTupleAppender(
+				FRAME_SIZE, fields);
+		FixedSizeFrameTupleAccessor ftacc = new FixedSizeFrameTupleAccessor(
+				FRAME_SIZE, fields);
+
+		boolean frameHasSpace = true;
+
+		ArrayList<Integer> check = new ArrayList<Integer>();
+
+		ftapp.reset(buffer, true);
+		while (frameHasSpace) {
+			int val = rnd.nextInt();
+			frameHasSpace = ftapp.append(val);
+			if (frameHasSpace) {
+				check.add(val);
+				ftapp.incrementTupleCount(1);
+			}
+		}
+
+		ftacc.reset(buffer);
+		for (int i = 0; i < ftacc.getTupleCount(); i++) {
+			int val = IntegerSerializerDeserializer.getInt(ftacc.getBuffer()
+					.array(), ftacc.getTupleStartOffset(i));
+			Assert.assertEquals(check.get(i).intValue(), val);
+		}
+	}
+}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/NGramTokenizerTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/NGramTokenizerTest.java
new file mode 100644
index 0000000..5f15a91
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/NGramTokenizerTest.java
@@ -0,0 +1,247 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.io.DataOutput;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.AbstractUTF8Token;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.HashedUTF8NGramTokenFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IToken;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.NGramUTF8StringBinaryTokenizer;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.UTF8NGramTokenFactory;
+
+public class NGramTokenizerTest {
+
+	private char PRECHAR = '#';
+	private char POSTCHAR = '$';
+
+	private String str = "Jürgen S. Generic's Car";
+	private byte[] inputBuffer;
+
+	private int gramLength = 3;
+
+	private void getExpectedGrams(String s, int gramLength,
+			ArrayList<String> grams, boolean prePost) {
+
+		String tmp = s.toLowerCase();
+		if (prePost) {
+			StringBuilder preBuilder = new StringBuilder();
+			for (int i = 0; i < gramLength - 1; i++) {
+				preBuilder.append(PRECHAR);
+			}
+			String pre = preBuilder.toString();
+
+			StringBuilder postBuilder = new StringBuilder();
+			for (int i = 0; i < gramLength - 1; i++) {
+				postBuilder.append(POSTCHAR);
+			}
+			String post = postBuilder.toString();
+
+			tmp = pre + s.toLowerCase() + post;
+		}
+
+		for (int i = 0; i < tmp.length() - gramLength + 1; i++) {
+			String gram = tmp.substring(i, i + gramLength);
+			grams.add(gram);
+		}
+	}
+
+	@Before
+	public void init() throws Exception {
+		// serialize string into bytes
+		ByteArrayOutputStream baos = new ByteArrayOutputStream();
+		DataOutput dos = new DataOutputStream(baos);
+		dos.writeUTF(str);
+		inputBuffer = baos.toByteArray();
+	}
+
+	void runTestNGramTokenizerWithCountedHashedUTF8Tokens(boolean prePost)
+			throws IOException {
+		HashedUTF8NGramTokenFactory tokenFactory = new HashedUTF8NGramTokenFactory();
+		NGramUTF8StringBinaryTokenizer tokenizer = new NGramUTF8StringBinaryTokenizer(
+				gramLength, prePost, false, false, tokenFactory);
+		tokenizer.reset(inputBuffer, 0, inputBuffer.length);
+
+		ArrayList<String> expectedGrams = new ArrayList<String>();
+		getExpectedGrams(str, gramLength, expectedGrams, prePost);
+		ArrayList<Integer> expectedHashedGrams = new ArrayList<Integer>();
+		HashMap<String, Integer> gramCounts = new HashMap<String, Integer>();
+		for (String s : expectedGrams) {
+			Integer count = gramCounts.get(s);
+			if (count == null) {
+				count = 1;
+				gramCounts.put(s, count);
+			} else {
+				count++;
+			}
+
+			int hash = tokenHash(s, count);
+			expectedHashedGrams.add(hash);
+		}
+
+		int tokenCount = 0;
+
+		while (tokenizer.hasNext()) {
+			tokenizer.next();
+
+			// serialize hashed token
+			ByteArrayOutputStream tokenBaos = new ByteArrayOutputStream();
+			DataOutput tokenDos = new DataOutputStream(tokenBaos);
+
+			IToken token = tokenizer.getToken();
+			token.serializeToken(tokenDos);
+
+			// deserialize token
+			ByteArrayInputStream bais = new ByteArrayInputStream(
+					tokenBaos.toByteArray());
+			DataInput in = new DataInputStream(bais);
+
+			Integer hashedGram = in.readInt();
+
+			// System.out.println(hashedGram);
+
+			Assert.assertEquals(expectedHashedGrams.get(tokenCount), hashedGram);
+
+			tokenCount++;
+		}
+		// System.out.println("---------");
+	}
+
+	void runTestNGramTokenizerWithHashedUTF8Tokens(boolean prePost)
+			throws IOException {
+		HashedUTF8NGramTokenFactory tokenFactory = new HashedUTF8NGramTokenFactory();
+		NGramUTF8StringBinaryTokenizer tokenizer = new NGramUTF8StringBinaryTokenizer(
+				gramLength, prePost, true, false, tokenFactory);
+		tokenizer.reset(inputBuffer, 0, inputBuffer.length);
+
+		ArrayList<String> expectedGrams = new ArrayList<String>();
+		getExpectedGrams(str, gramLength, expectedGrams, prePost);
+		ArrayList<Integer> expectedHashedGrams = new ArrayList<Integer>();
+		for (String s : expectedGrams) {
+			int hash = tokenHash(s, 1);
+			expectedHashedGrams.add(hash);
+		}
+
+		int tokenCount = 0;
+
+		while (tokenizer.hasNext()) {
+			tokenizer.next();
+
+			// serialize hashed token
+			ByteArrayOutputStream tokenBaos = new ByteArrayOutputStream();
+			DataOutput tokenDos = new DataOutputStream(tokenBaos);
+
+			IToken token = tokenizer.getToken();
+			token.serializeToken(tokenDos);
+
+			// deserialize token
+			ByteArrayInputStream bais = new ByteArrayInputStream(
+					tokenBaos.toByteArray());
+			DataInput in = new DataInputStream(bais);
+
+			Integer hashedGram = in.readInt();
+
+			// System.out.println(hashedGram);
+
+			Assert.assertEquals(expectedHashedGrams.get(tokenCount), hashedGram);
+
+			tokenCount++;
+		}
+		// System.out.println("---------");
+	}
+
+	void runTestNGramTokenizerWithUTF8Tokens(boolean prePost)
+			throws IOException {
+		UTF8NGramTokenFactory tokenFactory = new UTF8NGramTokenFactory();
+		NGramUTF8StringBinaryTokenizer tokenizer = new NGramUTF8StringBinaryTokenizer(
+				gramLength, prePost, true, false, tokenFactory);
+		tokenizer.reset(inputBuffer, 0, inputBuffer.length);
+
+		ArrayList<String> expectedGrams = new ArrayList<String>();
+		getExpectedGrams(str, gramLength, expectedGrams, prePost);
+
+		int tokenCount = 0;
+
+		while (tokenizer.hasNext()) {
+			tokenizer.next();
+
+			// serialize hashed token
+			ByteArrayOutputStream tokenBaos = new ByteArrayOutputStream();
+			DataOutput tokenDos = new DataOutputStream(tokenBaos);
+
+			IToken token = tokenizer.getToken();
+			token.serializeToken(tokenDos);
+
+			// deserialize token
+			ByteArrayInputStream bais = new ByteArrayInputStream(
+					tokenBaos.toByteArray());
+			DataInput in = new DataInputStream(bais);
+
+			String strGram = in.readUTF();
+
+			// System.out.println("\"" + strGram + "\"");
+
+			Assert.assertEquals(expectedGrams.get(tokenCount), strGram);
+
+			tokenCount++;
+		}
+		// System.out.println("---------");
+	}
+
+	@Test
+	public void testNGramTokenizerWithCountedHashedUTF8Tokens()
+			throws Exception {
+		runTestNGramTokenizerWithCountedHashedUTF8Tokens(false);
+		runTestNGramTokenizerWithCountedHashedUTF8Tokens(true);
+	}
+
+	@Test
+	public void testNGramTokenizerWithHashedUTF8Tokens() throws Exception {
+		runTestNGramTokenizerWithHashedUTF8Tokens(false);
+		runTestNGramTokenizerWithHashedUTF8Tokens(true);
+	}
+
+	@Test
+	public void testNGramTokenizerWithUTF8Tokens() throws IOException {
+		runTestNGramTokenizerWithUTF8Tokens(false);
+		runTestNGramTokenizerWithUTF8Tokens(true);
+	}
+
+	public int tokenHash(String token, int tokenCount) {
+		int h = AbstractUTF8Token.GOLDEN_RATIO_32;
+		for (int i = 0; i < token.length(); i++) {
+			h ^= token.charAt(i);
+			h *= AbstractUTF8Token.GOLDEN_RATIO_32;
+		}
+		return h + tokenCount;
+	}
+}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchPerfTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchPerfTest.java
new file mode 100644
index 0000000..161f20f
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchPerfTest.java
@@ -0,0 +1,292 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexSearchModifier;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.FixedSizeElementInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.OccurrenceThresholdPanicException;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.SearchResultCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.TOccurrenceSearcher;
+import edu.uci.ics.hyracks.storage.am.invertedindex.searchmodifiers.ConjunctiveSearchModifier;
+import edu.uci.ics.hyracks.storage.am.invertedindex.searchmodifiers.JaccardSearchModifier;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.DelimitedUTF8StringBinaryTokenizer;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.UTF8WordTokenFactory;
+
+/**
+ * The purpose of this test is to evaluate the performance of searches against
+ * an inverted index. First, we generate random <token, id> pairs sorted on
+ * token, which are bulk loaded into an inverted index. Next, we build random
+ * queries from a list of predefined tokens in the index, and measure the
+ * performance of executing them with different search modifiers. We test the
+ * ConjunctiveSearchModifier and the JaccardSearchModifier.
+ * 
+ */
+public class SearchPerfTest extends AbstractInvIndexSearchTest {
+
+	protected List<String> tokens = new ArrayList<String>();
+
+	@Before
+	public void start() throws Exception {
+		super.start();
+		tokenFactory = new UTF8WordTokenFactory();
+		tokenizer = new DelimitedUTF8StringBinaryTokenizer(true, false,
+				tokenFactory);
+		searcher = new TOccurrenceSearcher(stageletCtx, invIndex, tokenizer);
+		resultCursor = new SearchResultCursor(
+				searcher.createResultFrameTupleAccessor(),
+				searcher.createResultTupleReference());
+		loadData();
+	}
+
+	public void loadData() throws HyracksDataException {
+		tokens.add("compilers");
+		tokens.add("computer");
+		tokens.add("databases");
+		tokens.add("fast");
+		tokens.add("hyracks");
+		tokens.add("major");
+		tokens.add("science");
+		tokens.add("systems");
+		tokens.add("university");
+
+		for (int i = 0; i < tokens.size(); i++) {
+			checkInvLists.add(new ArrayList<Integer>());
+		}
+
+		// for generating length-skewed inverted lists
+		int addProb = 0;
+		int addProbStep = 10;
+
+		IInvertedListBuilder invListBuilder = new FixedSizeElementInvertedListBuilder(
+				invListTypeTraits);
+		InvertedIndex.BulkLoadContext ctx = invIndex.beginBulkLoad(
+				invListBuilder, HYRACKS_FRAME_SIZE, BTree.DEFAULT_FILL_FACTOR);
+
+		int totalElements = 0;
+		for (int i = 0; i < tokens.size(); i++) {
+
+			addProb += addProbStep * (i + 1);
+			for (int j = 0; j < maxId; j++) {
+				if ((Math.abs(rnd.nextInt()) % addProb) == 0) {
+
+					totalElements++;
+
+					tb.reset();
+					UTF8StringSerializerDeserializer.INSTANCE.serialize(
+							tokens.get(i), dos);
+					tb.addFieldEndOffset();
+					IntegerSerializerDeserializer.INSTANCE.serialize(j, dos);
+					tb.addFieldEndOffset();
+
+					checkInvLists.get(i).add(j);
+
+					appender.reset(frame, true);
+					appender.append(tb.getFieldEndOffsets(), tb.getByteArray(),
+							0, tb.getSize());
+
+					tuple.reset(accessor, 0);
+
+					try {
+						invIndex.bulkLoadAddTuple(ctx, tuple);
+					} catch (Exception e) {
+						e.printStackTrace();
+					}
+				}
+			}
+		}
+		invIndex.endBulkLoad(ctx);
+	}
+
+	/**
+	 * Determine the expected results with the ScanCount algorithm. The
+	 * ScanCount algorithm is very simple, so we can be confident the results
+	 * are correct.
+	 * 
+	 */
+	protected void fillExpectedResults(int[] queryTokenIndexes,
+			int numQueryTokens, int occurrenceThreshold) {
+		// reset scan count array
+		for (int i = 0; i < maxId; i++) {
+			scanCountArray[i] = 0;
+		}
+
+		// count occurrences
+		for (int i = 0; i < numQueryTokens; i++) {
+			ArrayList<Integer> list = checkInvLists.get(queryTokenIndexes[i]);
+			for (int j = 0; j < list.size(); j++) {
+				scanCountArray[list.get(j)]++;
+			}
+		}
+
+		// check threshold
+		expectedResults.clear();
+		for (int i = 0; i < maxId; i++) {
+			if (scanCountArray[i] >= occurrenceThreshold) {
+				expectedResults.add(i);
+			}
+		}
+	}
+
+	/**
+	 * Generates a specified number of queries. Each query consists of a set of
+	 * randomly chosen tokens that are picked from the pre-defined set of
+	 * tokens. We run each query, measure it's time, and verify it's results
+	 * against the results produced by ScanCount, implemented in
+	 * fillExpectedResults().
+	 * 
+	 */
+	private void runQueries(IInvertedIndexSearchModifier searchModifier,
+			int numQueries) throws Exception {
+
+		rnd.setSeed(50);
+
+		// generate random queries
+		int[] queryTokenIndexes = new int[tokens.size()];
+		for (int i = 0; i < numQueries; i++) {
+
+			int numQueryTokens = Math.abs(rnd.nextInt() % tokens.size()) + 1;
+			for (int j = 0; j < numQueryTokens; j++) {
+				queryTokenIndexes[j] = Math.abs(rnd.nextInt() % tokens.size());
+			}
+
+			StringBuilder strBuilder = new StringBuilder();
+			for (int j = 0; j < numQueryTokens; j++) {
+				strBuilder.append(tokens.get(queryTokenIndexes[j]));
+				if (j + 1 != numQueryTokens)
+					strBuilder.append(" ");
+			}
+
+			String queryString = strBuilder.toString();
+
+			queryTb.reset();
+			UTF8StringSerializerDeserializer.INSTANCE.serialize(queryString,
+					queryDos);
+			queryTb.addFieldEndOffset();
+
+			queryAppender.reset(frame, true);
+			queryAppender.append(queryTb.getFieldEndOffsets(),
+					queryTb.getByteArray(), 0, queryTb.getSize());
+			queryTuple.reset(queryAccessor, 0);
+
+			boolean panic = false;
+
+			int repeats = 1;
+			double totalTime = 0;
+			for (int j = 0; j < repeats; j++) {
+				long timeStart = System.currentTimeMillis();
+				try {
+					searcher.reset();
+					searcher.search(resultCursor, queryTuple, 0, searchModifier);
+				} catch (OccurrenceThresholdPanicException e) {
+					panic = true;
+				}
+				long timeEnd = System.currentTimeMillis();
+				totalTime += timeEnd - timeStart;
+			}
+			double avgTime = totalTime / (double) repeats;
+			LOGGER.info(i + ": " + "\"" + queryString + "\": " + avgTime + "ms");
+
+			if (!panic) {
+
+				fillExpectedResults(queryTokenIndexes, numQueryTokens,
+						searcher.getOccurrenceThreshold());
+
+				// verify results
+				int checkIndex = 0;
+				while (resultCursor.hasNext()) {
+					resultCursor.next();
+					ITupleReference resultTuple = resultCursor.getTuple();
+					int id = IntegerSerializerDeserializer.getInt(
+							resultTuple.getFieldData(0),
+							resultTuple.getFieldStart(0));
+					Assert.assertEquals(expectedResults.get(checkIndex)
+							.intValue(), id);
+					checkIndex++;
+				}
+
+				if (expectedResults.size() != checkIndex) {
+					LOGGER.info("CHECKING");
+					StringBuilder expectedStrBuilder = new StringBuilder();
+					for (Integer x : expectedResults) {
+						expectedStrBuilder.append(x + " ");
+					}
+					LOGGER.info(expectedStrBuilder.toString());
+				}
+
+				Assert.assertEquals(expectedResults.size(), checkIndex);
+			}
+		}
+	}
+
+	/**
+	 * Runs 50 random conjunctive search queries to test the
+	 * ConjunctiveSearchModifier.
+	 * 
+	 */
+	@Test
+	public void conjunctiveKeywordQueryTest() throws Exception {
+		IInvertedIndexSearchModifier searchModifier = new ConjunctiveSearchModifier();
+		runQueries(searchModifier, 50);
+	}
+
+	/**
+	 * Runs 50 random jaccard-based search queries with thresholds 1.0, 0.9,
+	 * 0.8, 0.7, 0.6, 0.5. Tests the JaccardSearchModifier.
+	 * 
+	 */
+	@Test
+	public void jaccardKeywordQueryTest() throws Exception {
+		JaccardSearchModifier searchModifier = new JaccardSearchModifier(1.0f);
+
+		LOGGER.info("JACCARD: " + 1.0f);
+		searchModifier.setJaccThresh(1.0f);
+		runQueries(searchModifier, 50);
+
+		LOGGER.info("JACCARD: " + 0.9f);
+		searchModifier.setJaccThresh(0.9f);
+		runQueries(searchModifier, 50);
+
+		LOGGER.info("JACCARD: " + 0.8f);
+		searchModifier.setJaccThresh(0.8f);
+		runQueries(searchModifier, 50);
+
+		LOGGER.info("JACCARD: " + 0.7f);
+		searchModifier.setJaccThresh(0.7f);
+		runQueries(searchModifier, 50);
+
+		LOGGER.info("JACCARD: " + 0.6f);
+		searchModifier.setJaccThresh(0.6f);
+		runQueries(searchModifier, 50);
+
+		LOGGER.info("JACCARD: " + 0.5f);
+		searchModifier.setJaccThresh(0.5f);
+		runQueries(searchModifier, 50);
+	}
+}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchTest.java
new file mode 100644
index 0000000..d9fef2c
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/SearchTest.java
@@ -0,0 +1,276 @@
+package edu.uci.ics.hyracks.storage.am.invertedindex;
+
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ByteArrayAccessibleOutputStream;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexSearchModifier;
+import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.FixedSizeElementInvertedListBuilder;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.InvertedIndex;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.OccurrenceThresholdPanicException;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.SearchResultCursor;
+import edu.uci.ics.hyracks.storage.am.invertedindex.impls.TOccurrenceSearcher;
+import edu.uci.ics.hyracks.storage.am.invertedindex.searchmodifiers.ConjunctiveSearchModifier;
+import edu.uci.ics.hyracks.storage.am.invertedindex.searchmodifiers.EditDistanceSearchModifier;
+import edu.uci.ics.hyracks.storage.am.invertedindex.searchmodifiers.JaccardSearchModifier;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IToken;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.NGramUTF8StringBinaryTokenizer;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.UTF8NGramTokenFactory;
+
+public class SearchTest extends AbstractInvIndexSearchTest {
+
+	protected List<String> dataStrings = new ArrayList<String>();
+	protected List<String> firstNames = new ArrayList<String>();
+	protected List<String> lastNames = new ArrayList<String>();
+
+	@Before
+	public void start() throws Exception {
+		super.start();
+		tokenFactory = new UTF8NGramTokenFactory();
+		tokenizer = new NGramUTF8StringBinaryTokenizer(3, false, true, false,
+				tokenFactory);
+		searcher = new TOccurrenceSearcher(stageletCtx, invIndex, tokenizer);
+		resultCursor = new SearchResultCursor(
+				searcher.createResultFrameTupleAccessor(),
+				searcher.createResultTupleReference());
+		generateDataStrings();
+		loadData();
+	}
+
+	public void generateDataStrings() {
+		firstNames.add("Kathrin");
+		firstNames.add("Cathrin");
+		firstNames.add("Kathryn");
+		firstNames.add("Cathryn");
+		firstNames.add("Kathrine");
+		firstNames.add("Cathrine");
+		firstNames.add("Kathryne");
+		firstNames.add("Cathryne");
+		firstNames.add("Katherin");
+		firstNames.add("Catherin");
+		firstNames.add("Katheryn");
+		firstNames.add("Catheryn");
+		firstNames.add("Katherine");
+		firstNames.add("Catherine");
+		firstNames.add("Katheryne");
+		firstNames.add("Catheryne");
+		firstNames.add("John");
+		firstNames.add("Jack");
+		firstNames.add("Jonathan");
+		firstNames.add("Nathan");
+
+		lastNames.add("Miller");
+		lastNames.add("Myller");
+		lastNames.add("Keller");
+		lastNames.add("Ketler");
+		lastNames.add("Muller");
+		lastNames.add("Fuller");
+		lastNames.add("Smith");
+		lastNames.add("Smyth");
+		lastNames.add("Smithe");
+		lastNames.add("Smythe");
+
+		// Generate all 'firstName lastName' combinations as data strings
+		for (String f : firstNames) {
+			for (String l : lastNames) {
+				dataStrings.add(f + " " + l);
+			}
+		}
+	}
+
+	private class TokenIdPair implements Comparable<TokenIdPair> {
+		public ByteArrayAccessibleOutputStream baaos = new ByteArrayAccessibleOutputStream();
+		public DataOutputStream dos = new DataOutputStream(baaos);
+		public int id;
+
+		TokenIdPair(IToken token, int id) throws IOException {
+			token.serializeToken(dos);
+			this.id = id;
+		}
+
+		@Override
+		public int compareTo(TokenIdPair o) {
+			int cmp = btreeBinCmps[0].compare(baaos.getByteArray(), 0,
+					baaos.getByteArray().length, o.baaos.getByteArray(), 0,
+					o.baaos.getByteArray().length);
+			if (cmp == 0) {
+				return id - o.id;
+			} else {
+				return cmp;
+			}
+		}
+	}
+
+	public void loadData() throws IOException {
+		List<TokenIdPair> pairs = new ArrayList<TokenIdPair>();
+		// generate pairs for subsequent sorting and bulk-loading
+		int id = 0;
+		for (String s : dataStrings) {
+			ByteArrayAccessibleOutputStream baaos = new ByteArrayAccessibleOutputStream();
+			DataOutputStream dos = new DataOutputStream(baaos);
+			UTF8StringSerializerDeserializer.INSTANCE.serialize(s, dos);
+			tokenizer.reset(baaos.getByteArray(), 0, baaos.size());
+			int tokenCount = 0;
+			while (tokenizer.hasNext()) {
+				tokenizer.next();
+				IToken token = tokenizer.getToken();
+				pairs.add(new TokenIdPair(token, id));
+				++tokenCount;
+			}
+			++id;
+		}
+		Collections.sort(pairs);
+
+		// bulk load index
+		IInvertedListBuilder invListBuilder = new FixedSizeElementInvertedListBuilder(
+				invListTypeTraits);
+		InvertedIndex.BulkLoadContext ctx = invIndex.beginBulkLoad(
+				invListBuilder, HYRACKS_FRAME_SIZE, BTree.DEFAULT_FILL_FACTOR);
+
+		for (TokenIdPair t : pairs) {
+			tb.reset();
+			tb.addField(t.baaos.getByteArray(), 0,
+					t.baaos.getByteArray().length);
+			IntegerSerializerDeserializer.INSTANCE.serialize(t.id, dos);
+			tb.addFieldEndOffset();
+
+			appender.reset(frame, true);
+			appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0,
+					tb.getSize());
+
+			tuple.reset(accessor, 0);
+
+			try {
+				invIndex.bulkLoadAddTuple(ctx, tuple);
+			} catch (Exception e) {
+				e.printStackTrace();
+			}
+		}
+		invIndex.endBulkLoad(ctx);
+	}
+
+	/**
+	 * Runs a specified number of randomly picked strings from dataStrings as
+	 * queries. We run each query, measure it's time, and print it's results.
+	 * 
+	 */
+	private void runQueries(IInvertedIndexSearchModifier searchModifier,
+			int numQueries) throws Exception {
+
+		rnd.setSeed(50);
+
+		for (int i = 0; i < numQueries; i++) {
+
+			int queryIndex = Math.abs(rnd.nextInt() % dataStrings.size());
+			String queryString = dataStrings.get(queryIndex);
+
+			queryTb.reset();
+			UTF8StringSerializerDeserializer.INSTANCE.serialize(queryString,
+					queryDos);
+			queryTb.addFieldEndOffset();
+
+			queryAppender.reset(frame, true);
+			queryAppender.append(queryTb.getFieldEndOffsets(),
+					queryTb.getByteArray(), 0, queryTb.getSize());
+			queryTuple.reset(queryAccessor, 0);
+
+			int repeats = 1;
+			double totalTime = 0;
+			for (int j = 0; j < repeats; j++) {
+				long timeStart = System.currentTimeMillis();
+				try {
+					searcher.reset();
+					searcher.search(resultCursor, queryTuple, 0, searchModifier);
+				} catch (OccurrenceThresholdPanicException e) {
+					// ignore panic queries
+				}
+				long timeEnd = System.currentTimeMillis();
+				totalTime += timeEnd - timeStart;
+			}
+			double avgTime = totalTime / (double) repeats;
+			StringBuilder strBuilder = new StringBuilder();
+			strBuilder.append(i + ": " + "\"" + queryString + "\": " + avgTime
+					+ "ms" + "\n");
+			strBuilder.append("CANDIDATE RESULTS:\n");
+			while (resultCursor.hasNext()) {
+				resultCursor.next();
+				ITupleReference resultTuple = resultCursor.getTuple();
+				int id = IntegerSerializerDeserializer.getInt(
+						resultTuple.getFieldData(0),
+						resultTuple.getFieldStart(0));
+				strBuilder.append(id + " " + dataStrings.get(id));
+				strBuilder.append('\n');
+			}
+			// remove trailing newline
+			strBuilder.deleteCharAt(strBuilder.length() - 1);
+			LOGGER.info(strBuilder.toString());
+		}
+	}
+
+	/**
+	 * Runs 5 random conjunctive search queries to test the
+	 * ConjunctiveSearchModifier.
+	 * 
+	 */
+	@Test
+	public void conjunctiveQueryTest() throws Exception {
+		IInvertedIndexSearchModifier searchModifier = new ConjunctiveSearchModifier();
+		runQueries(searchModifier, 5);
+	}
+
+	/**
+	 * Runs 5 random jaccard-based search queries with thresholds 0.9, 0.8, 0.7.
+	 * Tests the JaccardSearchModifier.
+	 * 
+	 */
+	@Test
+	public void jaccardQueryTest() throws Exception {
+		JaccardSearchModifier searchModifier = new JaccardSearchModifier(1.0f);
+
+		LOGGER.info("JACCARD: " + 0.9f);
+		searchModifier.setJaccThresh(0.9f);
+		runQueries(searchModifier, 5);
+
+		LOGGER.info("JACCARD: " + 0.8f);
+		searchModifier.setJaccThresh(0.8f);
+		runQueries(searchModifier, 5);
+
+		LOGGER.info("JACCARD: " + 0.7f);
+		searchModifier.setJaccThresh(0.7f);
+		runQueries(searchModifier, 5);
+	}
+
+	/**
+	 * Runs 5 random edit-distance based search queries with thresholds 1, 2, 3.
+	 * Tests the EditDistanceSearchModifier.
+	 * 
+	 */
+	@Test
+	public void editDistanceQueryTest() throws Exception {
+		EditDistanceSearchModifier searchModifier = new EditDistanceSearchModifier(
+				3, 0);
+
+		LOGGER.info("EDIT DISTANCE: " + 1);
+		searchModifier.setEdThresh(1);
+		runQueries(searchModifier, 5);
+
+		LOGGER.info("EDIT DISTANCE: " + 2);
+		searchModifier.setEdThresh(2);
+		runQueries(searchModifier, 5);
+
+		LOGGER.info("EDIT DISTANCE: " + 3);
+		searchModifier.setEdThresh(3);
+		runQueries(searchModifier, 5);
+	}
+}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/WordTokenizerTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/WordTokenizerTest.java
new file mode 100644
index 0000000..57fe306
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/WordTokenizerTest.java
@@ -0,0 +1,222 @@
+/**
+ * Copyright 2010-2011 The Regents of the University of California
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on
+ * an "AS IS"; BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under
+ * the License.
+ * 
+ * Author: Alexander Behm <abehm (at) ics.uci.edu>
+ */
+
+package edu.uci.ics.hyracks.storage.am.invertedindex;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.io.DataOutput;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+
+import junit.framework.Assert;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.AbstractUTF8Token;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.DelimitedUTF8StringBinaryTokenizer;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.HashedUTF8WordTokenFactory;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.IToken;
+import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.UTF8WordTokenFactory;
+
+public class WordTokenizerTest {
+
+	private String text = "Hello World, I would like to inform you of the importance of Foo Bar. Yes, Foo Bar. Jürgen.";
+	private byte[] inputBuffer;
+
+	private ArrayList<String> expectedUTF8Tokens = new ArrayList<String>();
+	private ArrayList<Integer> expectedHashedUTF8Tokens = new ArrayList<Integer>();
+	private ArrayList<Integer> expectedCountedHashedUTF8Tokens = new ArrayList<Integer>();
+
+	@Before
+	public void init() throws IOException {
+		// serialize text into bytes
+		ByteArrayOutputStream baos = new ByteArrayOutputStream();
+		DataOutput dos = new DataOutputStream(baos);
+		dos.writeUTF(text);
+		inputBuffer = baos.toByteArray();
+
+		// init expected string tokens
+		expectedUTF8Tokens.add("hello");
+		expectedUTF8Tokens.add("world");
+		expectedUTF8Tokens.add("i");
+		expectedUTF8Tokens.add("would");
+		expectedUTF8Tokens.add("like");
+		expectedUTF8Tokens.add("to");
+		expectedUTF8Tokens.add("inform");
+		expectedUTF8Tokens.add("you");
+		expectedUTF8Tokens.add("of");
+		expectedUTF8Tokens.add("the");
+		expectedUTF8Tokens.add("importance");
+		expectedUTF8Tokens.add("of");
+		expectedUTF8Tokens.add("foo");
+		expectedUTF8Tokens.add("bar");
+		expectedUTF8Tokens.add("yes");
+		expectedUTF8Tokens.add("foo");
+		expectedUTF8Tokens.add("bar");
+		expectedUTF8Tokens.add("jürgen");
+
+		// hashed tokens ignoring token count
+		for (int i = 0; i < expectedUTF8Tokens.size(); i++) {
+			int hash = tokenHash(expectedUTF8Tokens.get(i), 1);
+			expectedHashedUTF8Tokens.add(hash);
+		}
+
+		// hashed tokens using token count
+		HashMap<String, Integer> tokenCounts = new HashMap<String, Integer>();
+		for (int i = 0; i < expectedUTF8Tokens.size(); i++) {
+			Integer count = tokenCounts.get(expectedUTF8Tokens.get(i));
+			if (count == null) {
+				count = 1;
+				tokenCounts.put(expectedUTF8Tokens.get(i), count);
+			} else {
+				count++;
+			}
+
+			int hash = tokenHash(expectedUTF8Tokens.get(i), count);
+			expectedCountedHashedUTF8Tokens.add(hash);
+		}
+	}
+
+	@Test
+	public void testWordTokenizerWithCountedHashedUTF8Tokens()
+			throws IOException {
+
+		HashedUTF8WordTokenFactory tokenFactory = new HashedUTF8WordTokenFactory();
+		DelimitedUTF8StringBinaryTokenizer tokenizer = new DelimitedUTF8StringBinaryTokenizer(
+				false, false, tokenFactory);
+
+		tokenizer.reset(inputBuffer, 0, inputBuffer.length);
+
+		int tokenCount = 0;
+
+		while (tokenizer.hasNext()) {
+			tokenizer.next();
+
+			// serialize token
+			ByteArrayOutputStream tokenBaos = new ByteArrayOutputStream();
+			DataOutput tokenDos = new DataOutputStream(tokenBaos);
+
+			IToken token = tokenizer.getToken();
+			token.serializeToken(tokenDos);
+
+			// deserialize token
+			ByteArrayInputStream bais = new ByteArrayInputStream(
+					tokenBaos.toByteArray());
+			DataInput in = new DataInputStream(bais);
+
+			Integer hashedToken = in.readInt();
+
+			// System.out.println(hashedToken);
+
+			Assert.assertEquals(hashedToken,
+					expectedCountedHashedUTF8Tokens.get(tokenCount));
+
+			tokenCount++;
+		}
+	}
+
+	@Test
+	public void testWordTokenizerWithHashedUTF8Tokens() throws IOException {
+
+		HashedUTF8WordTokenFactory tokenFactory = new HashedUTF8WordTokenFactory();
+		DelimitedUTF8StringBinaryTokenizer tokenizer = new DelimitedUTF8StringBinaryTokenizer(
+				true, false, tokenFactory);
+
+		tokenizer.reset(inputBuffer, 0, inputBuffer.length);
+
+		int tokenCount = 0;
+
+		while (tokenizer.hasNext()) {
+			tokenizer.next();
+
+			// serialize token
+			ByteArrayOutputStream tokenBaos = new ByteArrayOutputStream();
+			DataOutput tokenDos = new DataOutputStream(tokenBaos);
+
+			IToken token = tokenizer.getToken();
+			token.serializeToken(tokenDos);
+
+			// deserialize token
+			ByteArrayInputStream bais = new ByteArrayInputStream(
+					tokenBaos.toByteArray());
+			DataInput in = new DataInputStream(bais);
+
+			Integer hashedToken = in.readInt();
+
+			// System.out.println(hashedToken);
+
+			Assert.assertEquals(expectedHashedUTF8Tokens.get(tokenCount),
+					hashedToken);
+
+			tokenCount++;
+		}
+	}
+
+	@Test
+	public void testWordTokenizerWithUTF8Tokens() throws IOException {
+
+		UTF8WordTokenFactory tokenFactory = new UTF8WordTokenFactory();
+		DelimitedUTF8StringBinaryTokenizer tokenizer = new DelimitedUTF8StringBinaryTokenizer(
+				true, false, tokenFactory);
+
+		tokenizer.reset(inputBuffer, 0, inputBuffer.length);
+
+		int tokenCount = 0;
+
+		while (tokenizer.hasNext()) {
+			tokenizer.next();
+
+			// serialize hashed token
+			ByteArrayOutputStream tokenBaos = new ByteArrayOutputStream();
+			DataOutput tokenDos = new DataOutputStream(tokenBaos);
+
+			IToken token = tokenizer.getToken();
+			token.serializeToken(tokenDos);
+
+			// deserialize token
+			ByteArrayInputStream bais = new ByteArrayInputStream(
+					tokenBaos.toByteArray());
+			DataInput in = new DataInputStream(bais);
+
+			String strToken = in.readUTF();
+
+			// System.out.println(strToken);
+
+			Assert.assertEquals(expectedUTF8Tokens.get(tokenCount), strToken);
+
+			tokenCount++;
+		}
+	}
+
+	// JAQL
+	public int tokenHash(String token, int tokenCount) {
+		int h = AbstractUTF8Token.GOLDEN_RATIO_32;
+		for (int i = 0; i < token.length(); i++) {
+			h ^= token.charAt(i);
+			h *= AbstractUTF8Token.GOLDEN_RATIO_32;
+		}
+		return h + tokenCount;
+	}
+}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/AbstractInvIndexTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/AbstractInvIndexTest.java
deleted file mode 100644
index 5d2cfff..0000000
--- a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/AbstractInvIndexTest.java
+++ /dev/null
@@ -1,25 +0,0 @@
-package edu.uci.ics.hyracks.storage.am.invertedindex.searchers;
-
-import java.io.File;
-import java.text.SimpleDateFormat;
-import java.util.Date;
-
-import org.junit.AfterClass;
-
-public abstract class AbstractInvIndexTest {
-
-    protected final static SimpleDateFormat simpleDateFormat = new SimpleDateFormat("ddMMyy-hhmmssSS");
-    protected final static String tmpDir = System.getProperty("java.io.tmpdir");
-    protected final static String sep = System.getProperty("file.separator");
-    protected final static String fileName = tmpDir + sep + simpleDateFormat.format(new Date());
-
-    protected void print(String str) {
-        System.out.print(str);
-    }
-
-    @AfterClass
-    public static void cleanup() throws Exception {
-        File f = new File(fileName);
-        f.deleteOnExit();
-    }
-}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/SimpleConjunctiveSearcherTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/SimpleConjunctiveSearcherTest.java
deleted file mode 100644
index f61249b..0000000
--- a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/SimpleConjunctiveSearcherTest.java
+++ /dev/null
@@ -1,279 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.invertedindex.searchers;
-
-import java.io.ByteArrayInputStream;
-import java.io.DataInput;
-import java.io.DataInputStream;
-import java.io.DataOutput;
-import java.io.File;
-import java.nio.ByteBuffer;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Random;
-
-import org.junit.Test;
-
-import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
-import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
-import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
-import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
-import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
-import edu.uci.ics.hyracks.api.dataflow.value.TypeTrait;
-import edu.uci.ics.hyracks.api.io.FileReference;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
-import edu.uci.ics.hyracks.dataflow.common.data.accessors.FrameTupleReference;
-import edu.uci.ics.hyracks.dataflow.common.data.comparators.IntegerBinaryComparatorFactory;
-import edu.uci.ics.hyracks.dataflow.common.data.comparators.UTF8StringBinaryComparatorFactory;
-import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
-import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrame;
-import edu.uci.ics.hyracks.storage.am.btree.api.IBTreeMetaDataFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.MetaDataFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMInteriorFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.frames.NSMLeafFrameFactory;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTree;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
-import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
-import edu.uci.ics.hyracks.storage.am.btree.impls.MultiComparator;
-import edu.uci.ics.hyracks.storage.am.btree.tuples.TypeAwareTupleWriterFactory;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IBinaryTokenizer;
-import edu.uci.ics.hyracks.storage.am.invertedindex.api.IInvertedIndexResultCursor;
-import edu.uci.ics.hyracks.storage.am.invertedindex.impls.SimpleConjunctiveSearcher;
-import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.DelimitedUTF8StringBinaryTokenizer;
-import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
-import edu.uci.ics.hyracks.storage.common.buffercache.ICacheMemoryAllocator;
-import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
-import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
-import edu.uci.ics.hyracks.test.support.TestUtils;
-
-public class SimpleConjunctiveSearcherTest extends AbstractInvIndexTest {
-
-    // testing params
-    // private static final int PAGE_SIZE = 256;
-    // private static final int NUM_PAGES = 10;
-    // private static final int HYRACKS_FRAME_SIZE = 256;
-
-    // realistic params
-    // private static final int PAGE_SIZE = 65536;
-    private static final int PAGE_SIZE = 32768;
-    private static final int NUM_PAGES = 10;
-    private static final int HYRACKS_FRAME_SIZE = 32768;
-    private IHyracksStageletContext ctx = TestUtils.create(HYRACKS_FRAME_SIZE);
-
-    public class BufferAllocator implements ICacheMemoryAllocator {
-        @Override
-        public ByteBuffer[] allocate(int pageSize, int numPages) {
-            ByteBuffer[] buffers = new ByteBuffer[numPages];
-            for (int i = 0; i < numPages; ++i) {
-                buffers[i] = ByteBuffer.allocate(pageSize);
-            }
-            return buffers;
-        }
-    }
-
-    @Test
-    public void test01() throws Exception {
-
-        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES);
-        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
-        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
-        FileReference file = new FileReference(new File(fileName));
-        bufferCache.createFile(file);
-        int fileId = fmp.lookupFileId(file);
-        bufferCache.openFile(fileId);
-
-        // declare fields
-        int fieldCount = 2;
-        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
-        typeTraits[0] = new TypeTrait(ITypeTrait.VARIABLE_LENGTH);
-        typeTraits[1] = new TypeTrait(4);
-
-        // declare keys
-        int keyFieldCount = 2;
-        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
-        cmps[0] = UTF8StringBinaryComparatorFactory.INSTANCE.createBinaryComparator();
-        cmps[1] = IntegerBinaryComparatorFactory.INSTANCE.createBinaryComparator();
-
-        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
-
-        TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
-        // SimpleTupleWriterFactory tupleWriterFactory = new
-        // SimpleTupleWriterFactory();
-        IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(tupleWriterFactory);
-        // IBTreeLeafFrameFactory leafFrameFactory = new
-        // FieldPrefixNSMLeafFrameFactory(tupleWriterFactory);
-        IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(tupleWriterFactory);
-        IBTreeMetaDataFrameFactory metaFrameFactory = new MetaDataFrameFactory();
-
-        IBTreeLeafFrame leafFrame = leafFrameFactory.getFrame();
-        IBTreeInteriorFrame interiorFrame = interiorFrameFactory.getFrame();
-        IBTreeMetaDataFrame metaFrame = metaFrameFactory.getFrame();
-
-        BTree btree = new BTree(bufferCache, interiorFrameFactory, leafFrameFactory, cmp);
-        btree.create(fileId, leafFrame, metaFrame);
-        btree.open(fileId);
-
-        Random rnd = new Random();
-        rnd.setSeed(50);
-
-        ByteBuffer frame = ctx.allocateFrame();
-        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
-        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
-        DataOutput dos = tb.getDataOutput();
-
-        ISerializerDeserializer[] btreeSerde = { UTF8StringSerializerDeserializer.INSTANCE,
-                IntegerSerializerDeserializer.INSTANCE };
-        RecordDescriptor btreeRecDesc = new RecordDescriptor(btreeSerde);
-        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), btreeRecDesc);
-        accessor.reset(frame);
-        FrameTupleReference tuple = new FrameTupleReference();
-
-        List<String> tokens = new ArrayList<String>();
-        tokens.add("computer");
-        tokens.add("hyracks");
-        tokens.add("fast");
-        tokens.add("university");
-        tokens.add("science");
-        tokens.add("major");
-
-        int maxId = 10000;
-        int addProb = 0;
-        int addProbStep = 2;
-
-        BTreeOpContext opCtx = btree.createOpContext(BTreeOp.BTO_INSERT, leafFrame, interiorFrame, metaFrame);
-
-        for (int i = 0; i < tokens.size(); i++) {
-
-            addProb += addProbStep;
-            for (int j = 0; j < maxId; j++) {
-                if ((Math.abs(rnd.nextInt()) % addProb) == 0) {
-                    tb.reset();
-                    UTF8StringSerializerDeserializer.INSTANCE.serialize(tokens.get(i), dos);
-                    tb.addFieldEndOffset();
-                    IntegerSerializerDeserializer.INSTANCE.serialize(j, dos);
-                    tb.addFieldEndOffset();
-
-                    appender.reset(frame, true);
-                    appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
-
-                    tuple.reset(accessor, 0);
-
-                    try {
-                        btree.insert(tuple, opCtx);
-                    } catch (Exception e) {
-                        e.printStackTrace();
-                    }
-                }
-            }
-        }
-
-        int numPages = btree.getMaxPage(metaFrame);
-        System.out.println("NUMPAGES: " + numPages);
-
-        // build query as tuple reference
-        ISerializerDeserializer[] querySerde = { UTF8StringSerializerDeserializer.INSTANCE };
-        RecordDescriptor queryRecDesc = new RecordDescriptor(querySerde);
-
-        FrameTupleAppender queryAppender = new FrameTupleAppender(ctx.getFrameSize());
-        ArrayTupleBuilder queryTb = new ArrayTupleBuilder(querySerde.length);
-        DataOutput queryDos = queryTb.getDataOutput();
-
-        IFrameTupleAccessor queryAccessor = new FrameTupleAccessor(ctx.getFrameSize(), queryRecDesc);
-        queryAccessor.reset(frame);
-        FrameTupleReference queryTuple = new FrameTupleReference();
-
-        String query = "computer hyracks fast";
-        char queryDelimiter = ' ';
-        IBinaryTokenizer queryTokenizer = new DelimitedUTF8StringBinaryTokenizer(queryDelimiter);
-
-        queryTb.reset();
-        UTF8StringSerializerDeserializer.INSTANCE.serialize(query, queryDos);
-        queryTb.addFieldEndOffset();
-
-        queryAppender.reset(frame, true);
-        queryAppender.append(queryTb.getFieldEndOffsets(), queryTb.getByteArray(), 0, queryTb.getSize());
-        queryTuple.reset(queryAccessor, 0);
-
-        int numKeyFields = 1;
-        int numValueFields = 1;
-        ISerializerDeserializer[] resultSerde = new ISerializerDeserializer[numValueFields];
-        for (int i = 0; i < numValueFields; i++) {
-            resultSerde[i] = btreeSerde[numKeyFields + i];
-        }
-        RecordDescriptor resultRecDesc = new RecordDescriptor(resultSerde);
-        FrameTupleAccessor resultAccessor = new FrameTupleAccessor(ctx.getFrameSize(), resultRecDesc);
-        FrameTupleReference resultTuple = new FrameTupleReference();
-        
-        SimpleConjunctiveSearcher searcher = new SimpleConjunctiveSearcher(ctx, btree, btreeRecDesc, queryTokenizer,
-                numKeyFields, numValueFields);
-
-        long timeStart = System.currentTimeMillis();
-        searcher.search(queryTuple, 0);
-        long timeEnd = System.currentTimeMillis();
-        System.out.println("SEARCH TIME: " + (timeEnd - timeStart) + "ms");
-
-        // System.out.println("INTERSECTION RESULTS");
-        IInvertedIndexResultCursor resultCursor = searcher.getResultCursor();
-        while (resultCursor.hasNext()) {
-            resultCursor.next();
-            resultAccessor.reset(resultCursor.getBuffer());
-            for (int i = 0; i < resultAccessor.getTupleCount(); i++) {
-                resultTuple.reset(resultAccessor, i);
-                for (int j = 0; j < resultTuple.getFieldCount(); j++) {
-                    ByteArrayInputStream inStream = new ByteArrayInputStream(resultTuple.getFieldData(j), resultTuple
-                            .getFieldStart(j), resultTuple.getFieldLength(j));
-                    DataInput dataIn = new DataInputStream(inStream);
-                    Object o = resultSerde[j].deserialize(dataIn);
-                    System.out.print(o + " ");
-                }
-                System.out.println();
-            }
-        }
-
-        /*
-         * IBinaryComparator[] searchCmps = new IBinaryComparator[1];
-         * searchCmps[0] =
-         * UTF8StringBinaryComparatorFactory.INSTANCE.createBinaryComparator();
-         * MultiComparator searchCmp = new MultiComparator(typeTraits,
-         * searchCmps);
-         * 
-         * // ordered scan IBTreeCursor scanCursor = new
-         * RangeSearchCursor(leafFrame); RangePredicate nullPred = new
-         * RangePredicate(true, null, null, true, true, null); BTreeOpContext
-         * searchOpCtx = btree.createOpContext(BTreeOp.BTO_SEARCH, leafFrame,
-         * interiorFrame, metaFrame); btree.search(scanCursor, nullPred,
-         * searchOpCtx);
-         * 
-         * try { while (scanCursor.hasNext()) { scanCursor.next();
-         * ITupleReference frameTuple = scanCursor.getTuple(); String rec =
-         * cmp.printTuple(frameTuple, btreeSerde); System.out.println(rec); } }
-         * catch (Exception e) { e.printStackTrace(); } finally {
-         * scanCursor.close(); }
-         */
-
-        btree.close();
-        bufferCache.closeFile(fileId);
-        bufferCache.close();
-    }
-}
diff --git a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/TokenizerTest.java b/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/TokenizerTest.java
deleted file mode 100644
index 47c75cf..0000000
--- a/hyracks-tests/hyracks-storage-am-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/tokenizers/TokenizerTest.java
+++ /dev/null
@@ -1,194 +0,0 @@
-/*
- * Copyright 2009-2010 by The Regents of the University of California
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * you may obtain a copy of the License from
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers;
-
-import java.io.ByteArrayInputStream;
-import java.io.DataInput;
-import java.io.DataInputStream;
-import java.io.DataOutputStream;
-import java.util.ArrayList;
-import java.util.Random;
-
-import org.junit.Assert;
-import org.junit.Test;
-
-import edu.uci.ics.hyracks.api.dataflow.value.IBinaryHashFunction;
-import edu.uci.ics.hyracks.dataflow.common.comm.io.ByteArrayAccessibleOutputStream;
-import edu.uci.ics.hyracks.dataflow.common.data.hash.UTF8StringBinaryHashFunctionFactory;
-import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
-import edu.uci.ics.hyracks.dataflow.common.data.marshalling.UTF8StringSerializerDeserializer;
-
-public class TokenizerTest {
-
-    // testing DelimitedUTF8StringBinaryTokenizer
-    @Test
-    public void test01() throws Exception {
-        Random rnd = new Random(50);
-
-        int numDocs = 100;
-        int maxWords = 1000;
-        int maxWordLength = 50;
-        char delimiter = ' ';
-
-        DelimitedUTF8StringBinaryTokenizer tok = new DelimitedUTF8StringBinaryTokenizer(delimiter);
-
-        // create a bunch of documents
-        for (int i = 0; i < numDocs; i++) {
-
-            // create a single document with a bunch of words
-            int words = (Math.abs(rnd.nextInt()) % maxWords) + 1;
-            StringBuilder strBuilder = new StringBuilder();
-            for (int j = 0; j < words; j++) {
-                int len = (Math.abs(rnd.nextInt()) % maxWordLength) + 1;
-                String s = randomString(len, rnd);
-                strBuilder.append(s);
-                if (j < words - 1)
-                    strBuilder.append(delimiter);
-            }
-
-            String doc = strBuilder.toString();
-
-            // serialize document into baaos
-            ByteArrayAccessibleOutputStream baaos = new ByteArrayAccessibleOutputStream();
-            DataOutputStream dos = new DataOutputStream(baaos);
-            UTF8StringSerializerDeserializer.INSTANCE.serialize(doc, dos);
-            byte[] data = baaos.toByteArray();
-
-            // use binary tokenizer and compare with Java tokenizer
-            String[] cmpTokens = doc.split(new String(new char[] { delimiter }));
-            int cmpCounter = 0;
-
-            tok.reset(data, 0, data.length);
-            while (tok.hasNext()) {
-                tok.next();
-
-                // write token to outputstream
-                ByteArrayAccessibleOutputStream baaosWrite = new ByteArrayAccessibleOutputStream();
-                DataOutputStream dosWrite = new DataOutputStream(baaosWrite);
-                tok.writeToken(dosWrite);
-
-                // deserialize token to get string object
-                ByteArrayInputStream inStream = new ByteArrayInputStream(baaosWrite.toByteArray());
-                DataInput dataIn = new DataInputStream(inStream);
-                String s = UTF8StringSerializerDeserializer.INSTANCE.deserialize(dataIn);
-
-                Assert.assertEquals(s, cmpTokens[cmpCounter++]);
-            }
-        }
-    }
-
-    // testing HashedQGramUTF8StringBinaryTokenizer
-    @Test
-    public void test02() throws Exception {
-        Random rnd = new Random(50);
-
-        int numStrings = 1000;
-        int maxStrLen = 100;
-        int minQ = 2;
-        int maxQ = 10;
-
-        // we test the correctness of HashedQGramUTF8StringBinaryTokenizer as
-        // follows:
-        // 1.1. tokenize the string into q-gram strings
-        // 1.2. serialize q-gram strings into bytes
-        // 1.3. compute hashed gram with UTF8StringBinaryHashFunctionFactory
-        // 2.1. serialize string into bytes
-        // 2.2. tokenize serialized string into hashed q-grams
-        // 2.3. test whether hashed grams from 1.3. and 2.3. are equal
-        for (int i = 0; i < numStrings; i++) {
-            int q = (Math.abs(rnd.nextInt()) % (maxQ - minQ)) + minQ;
-            int strLen = (Math.abs(rnd.nextInt()) % (maxStrLen - q)) + q;
-            String str = randomString(strLen, rnd);
-
-            // randomly choose pre and postfixing
-            boolean prePost = false;
-            if (Math.abs(rnd.nextInt()) % 2 == 0)
-                prePost = true;
-
-            HashedQGramUTF8StringBinaryTokenizer qgramTok = new HashedQGramUTF8StringBinaryTokenizer(q, prePost);
-
-            String extendedString = str;
-            if (prePost) {
-                // pre and postfix string
-                StringBuilder strBuilder = new StringBuilder();
-                for (int j = 0; j < q - 1; j++)
-                    strBuilder.append(qgramTok.getPreChar());
-                strBuilder.append(str);
-                for (int j = 0; j < q - 1; j++)
-                    strBuilder.append(qgramTok.getPostChar());
-                extendedString = strBuilder.toString();
-            }
-
-            // generate q-grams in deserialized form
-            ArrayList<String> javaGrams = new ArrayList<String>();
-            for (int j = 0; j < extendedString.length() - q + 1; j++) {
-                javaGrams.add(extendedString.substring(j, j + q));
-            }
-
-            // serialize string for use in binary gram tokenizer
-            ByteArrayAccessibleOutputStream baaos = new ByteArrayAccessibleOutputStream();
-            DataOutputStream dos = new DataOutputStream(baaos);
-            UTF8StringSerializerDeserializer.INSTANCE.serialize(str, dos);
-            byte[] data = baaos.toByteArray();
-
-            qgramTok.reset(data, 0, data.length);
-
-            int counter = 0;
-            while (qgramTok.hasNext()) {
-                qgramTok.next();
-
-                // write token to outputstream
-                ByteArrayAccessibleOutputStream baaosWrite = new ByteArrayAccessibleOutputStream();
-                DataOutputStream dosWrite = new DataOutputStream(baaosWrite);
-                qgramTok.writeToken(dosWrite);
-
-                // deserialize token to get hashed gram
-                ByteArrayInputStream inStream = new ByteArrayInputStream(baaosWrite.toByteArray());
-                DataInput dataIn = new DataInputStream(inStream);
-                Integer binHashedGram = IntegerSerializerDeserializer.INSTANCE.deserialize(dataIn);
-
-                // create hashed gram to test against
-                ByteArrayAccessibleOutputStream baaosCmp = new ByteArrayAccessibleOutputStream();
-                DataOutputStream dosCmp = new DataOutputStream(baaosCmp);
-                UTF8StringSerializerDeserializer.INSTANCE.serialize(javaGrams.get(counter), dosCmp);
-
-                IBinaryHashFunction strHasher = UTF8StringBinaryHashFunctionFactory.INSTANCE.createBinaryHashFunction();
-                byte[] cmpData = baaosCmp.toByteArray();
-                int cmpHash = strHasher.hash(cmpData, 0, cmpData.length);
-
-                Assert.assertEquals(binHashedGram.intValue(), cmpHash);
-
-                counter++;
-            }
-        }
-    }
-
-    public static String randomString(int length, Random random) {
-        int maxAttempts = 1000;
-        int count = 0;
-        while (count < maxAttempts) {
-            String s = Long.toHexString(Double.doubleToLongBits(random.nextDouble()));
-            StringBuilder strBuilder = new StringBuilder();
-            for (int i = 0; i < s.length() && i < length; i++) {
-                strBuilder.append(s.charAt(Math.abs(random.nextInt()) % s.length()));
-            }
-            if (strBuilder.length() > 0)
-                return strBuilder.toString();
-            count++;
-        }
-        return "abc";
-    }
-}
diff --git a/hyracks-tests/hyracks-storage-am-rtree-test/.classpath b/hyracks-tests/hyracks-storage-am-rtree-test/.classpath
new file mode 100644
index 0000000..f2cc5f7
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-rtree-test/.classpath
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" output="target/test-classes" path="src/test/java"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.6"/>
+	<classpathentry kind="con" path="org.maven.ide.eclipse.MAVEN2_CLASSPATH_CONTAINER"/>
+	<classpathentry kind="output" path="target/classes"/>
+</classpath>
diff --git a/hyracks-storage-am-invertedindex/.project b/hyracks-tests/hyracks-storage-am-rtree-test/.project
similarity index 91%
copy from hyracks-storage-am-invertedindex/.project
copy to hyracks-tests/hyracks-storage-am-rtree-test/.project
index 9303fb7..ea7e36b 100644
--- a/hyracks-storage-am-invertedindex/.project
+++ b/hyracks-tests/hyracks-storage-am-rtree-test/.project
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <projectDescription>
-	<name>hyracks-storage-am-invertedindex</name>
+	<name>hyracks-storage-am-rtree-test</name>
 	<comment></comment>
 	<projects>
 	</projects>
diff --git a/hyracks-tests/hyracks-storage-am-rtree-test/.settings/org.eclipse.jdt.core.prefs b/hyracks-tests/hyracks-storage-am-rtree-test/.settings/org.eclipse.jdt.core.prefs
new file mode 100644
index 0000000..375e12e
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-rtree-test/.settings/org.eclipse.jdt.core.prefs
@@ -0,0 +1,6 @@
+#Fri May 20 19:34:07 PDT 2011
+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.6
+org.eclipse.jdt.core.compiler.compliance=1.6
+org.eclipse.jdt.core.compiler.problem.forbiddenReference=warning
+org.eclipse.jdt.core.compiler.source=1.6
diff --git a/hyracks-tests/hyracks-storage-am-rtree-test/.settings/org.maven.ide.eclipse.prefs b/hyracks-tests/hyracks-storage-am-rtree-test/.settings/org.maven.ide.eclipse.prefs
new file mode 100644
index 0000000..99b89a6
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-rtree-test/.settings/org.maven.ide.eclipse.prefs
@@ -0,0 +1,9 @@
+#Thu Jan 06 11:27:16 PST 2011
+activeProfiles=
+eclipse.preferences.version=1
+fullBuildGoals=process-test-resources
+includeModules=false
+resolveWorkspaceProjects=true
+resourceFilterGoals=process-resources resources\:testResources
+skipCompilerPlugin=true
+version=1
diff --git a/hyracks-tests/hyracks-storage-am-rtree-test/pom.xml b/hyracks-tests/hyracks-storage-am-rtree-test/pom.xml
new file mode 100644
index 0000000..6673481
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-rtree-test/pom.xml
@@ -0,0 +1,55 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>edu.uci.ics.hyracks</groupId>
+  <artifactId>hyracks-storage-am-rtree-test</artifactId>
+  <version>0.1.7-SNAPSHOT</version>
+
+  <parent>
+    <groupId>edu.uci.ics.hyracks</groupId>
+    <artifactId>hyracks-tests</artifactId>
+    <version>0.1.7-SNAPSHOT</version>
+  </parent>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>2.0.2</version>
+        <configuration>
+          <source>1.6</source>
+          <target>1.6</target>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+  <dependencies>
+  	<dependency>
+  		<groupId>junit</groupId>
+  		<artifactId>junit</artifactId>
+  		<version>4.8.1</version>
+  		<type>jar</type>
+  		<scope>test</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-control-nc</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<scope>compile</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-storage-am-rtree</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>compile</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-test-support</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>test</scope>
+  	</dependency>
+  </dependencies>
+</project>
diff --git a/hyracks-tests/hyracks-storage-am-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/rtree/AbstractRTreeTest.java b/hyracks-tests/hyracks-storage-am-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/rtree/AbstractRTreeTest.java
new file mode 100644
index 0000000..b2ab775
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/rtree/AbstractRTreeTest.java
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree;
+
+import java.io.File;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
+import org.junit.AfterClass;
+
+public abstract class AbstractRTreeTest {
+
+    protected final static SimpleDateFormat simpleDateFormat = new SimpleDateFormat("ddMMyy-hhmmssSS");
+    protected final static String tmpDir = System.getProperty("java.io.tmpdir");
+    protected final static String sep = System.getProperty("file.separator");
+    protected final static String fileName = tmpDir + sep + simpleDateFormat.format(new Date());
+
+    protected void print(String str) {
+        System.err.print(str);
+    }
+
+    @AfterClass
+    public static void cleanup() throws Exception {
+        File f = new File(fileName);
+        f.deleteOnExit();
+    }
+}
diff --git a/hyracks-tests/hyracks-storage-am-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/rtree/RTreeTest.java b/hyracks-tests/hyracks-storage-am-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/rtree/RTreeTest.java
new file mode 100644
index 0000000..72c3f38
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/rtree/RTreeTest.java
@@ -0,0 +1,570 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree;
+
+import java.io.DataOutput;
+import java.io.File;
+import java.nio.ByteBuffer;
+import java.util.Random;
+
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.dataflow.value.TypeTrait;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.FrameTupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.DoubleBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.DoubleSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.freepage.LinkedListFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.impls.TreeDiskOrderScanCursor;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.common.utility.TreeIndexStats;
+import edu.uci.ics.hyracks.storage.am.common.utility.TreeIndexStatsGatherer;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTree;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTreeOpContext;
+import edu.uci.ics.hyracks.storage.am.rtree.tuples.RTreeTypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
+import edu.uci.ics.hyracks.test.support.TestUtils;
+
+public class RTreeTest extends AbstractRTreeTest {
+
+    private static final int PAGE_SIZE = 256;
+    private static final int NUM_PAGES = 10;
+    private static final int MAX_OPEN_FILES = 10;
+    private static final int HYRACKS_FRAME_SIZE = 128;
+    private IHyracksStageletContext ctx = TestUtils.create(HYRACKS_FRAME_SIZE);
+
+    // create an R-tree of two dimensions
+    // fill the R-tree with random values using insertions
+    // perform ordered scan
+    @Test
+    public void test01() throws Exception {
+
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
+
+        // declare keys
+        int keyFieldCount = 4;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = DoubleBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        cmps[1] = cmps[0];
+        cmps[2] = cmps[0];
+        cmps[3] = cmps[0];
+
+        // declare tuple fields
+        int fieldCount = 7;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(8);
+        typeTraits[1] = new TypeTrait(8);
+        typeTraits[2] = new TypeTrait(8);
+        typeTraits[3] = new TypeTrait(8);
+        typeTraits[4] = new TypeTrait(8);
+        typeTraits[5] = new TypeTrait(4);
+        typeTraits[6] = new TypeTrait(8);
+
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+
+        RTreeTypeAwareTupleWriterFactory tupleWriterFactory = new RTreeTypeAwareTupleWriterFactory(typeTraits);
+
+        ITreeIndexFrameFactory interiorFrameFactory = new RTreeNSMInteriorFrameFactory(tupleWriterFactory,
+                keyFieldCount);
+        ITreeIndexFrameFactory leafFrameFactory = new RTreeNSMLeafFrameFactory(tupleWriterFactory, keyFieldCount);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
+
+        IRTreeFrame interiorFrame = (IRTreeFrame) interiorFrameFactory.createFrame();
+        IRTreeFrame leafFrame = (IRTreeFrame) leafFrameFactory.createFrame();
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
+
+        RTree rtree = new RTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        rtree.create(fileId, leafFrame, metaFrame);
+        rtree.open(fileId);
+
+        ByteBuffer hyracksFrame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
+
+        @SuppressWarnings("rawtypes")
+        ISerializerDeserializer[] recDescSers = { DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(hyracksFrame);
+        FrameTupleReference tuple = new FrameTupleReference();
+
+        RTreeOpContext insertOpCtx = rtree.createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
+
+        Random rnd = new Random();
+        rnd.setSeed(50);
+
+        Random rnd2 = new Random();
+        rnd2.setSeed(50);
+        for (int i = 0; i < 5000; i++) {
+
+            double p1x = rnd.nextDouble();
+            double p1y = rnd.nextDouble();
+            double p2x = rnd.nextDouble();
+            double p2y = rnd.nextDouble();
+
+            double pk1 = rnd2.nextDouble();
+            int pk2 = rnd2.nextInt();
+            double pk3 = rnd2.nextDouble();
+
+            tb.reset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(pk1, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(pk2, dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(pk3, dos);
+            tb.addFieldEndOffset();
+
+            appender.reset(hyracksFrame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
+
+            tuple.reset(accessor, 0);
+
+            if (i % 1000 == 0) {
+                print("INSERTING " + i + " " + Math.min(p1x, p2x) + " " + Math.min(p1y, p2y) + " " + Math.max(p1x, p2x)
+                        + " " + Math.max(p1y, p2y) + "\n");
+            }
+
+            try {
+                rtree.insert(tuple, insertOpCtx);
+            } catch (TreeIndexException e) {
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+
+        // rtree.printTree(leafFrame, interiorFrame, recDescSers);
+        // System.err.println();
+
+        String rtreeStats = rtree.printStats();
+        print(rtreeStats);
+
+        // disk-order scan
+        print("DISK-ORDER SCAN:\n");
+        TreeDiskOrderScanCursor diskOrderCursor = new TreeDiskOrderScanCursor(leafFrame);
+        RTreeOpContext diskOrderScanOpCtx = rtree.createOpContext(IndexOp.DISKORDERSCAN, leafFrame, null, null);
+        rtree.diskOrderScan(diskOrderCursor, leafFrame, metaFrame, diskOrderScanOpCtx);
+        try {
+            while (diskOrderCursor.hasNext()) {
+                diskOrderCursor.next();
+                ITupleReference frameTuple = diskOrderCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                print(rec + "\n");
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            diskOrderCursor.close();
+        }
+
+        TreeIndexStatsGatherer statsGatherer = new TreeIndexStatsGatherer(bufferCache, freePageManager, fileId,
+                rtree.getRootPageId());
+        TreeIndexStats stats = statsGatherer.gatherStats(leafFrame, interiorFrame, metaFrame);
+        String string = stats.toString();
+        System.err.println(string);
+
+        rtree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+
+    }
+
+    // create an R-tree of two dimensions
+    // fill the R-tree with random values using insertions
+    // and then delete all the tuples which result of an empty R-tree
+    @Test
+    public void test02() throws Exception {
+
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
+
+        // declare keys
+        int keyFieldCount = 4;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = DoubleBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        cmps[1] = cmps[0];
+        cmps[2] = cmps[0];
+        cmps[3] = cmps[0];
+
+        // declare tuple fields
+        int fieldCount = 7;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(8);
+        typeTraits[1] = new TypeTrait(8);
+        typeTraits[2] = new TypeTrait(8);
+        typeTraits[3] = new TypeTrait(8);
+        typeTraits[4] = new TypeTrait(8);
+        typeTraits[5] = new TypeTrait(4);
+        typeTraits[6] = new TypeTrait(8);
+
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+
+        RTreeTypeAwareTupleWriterFactory tupleWriterFactory = new RTreeTypeAwareTupleWriterFactory(typeTraits);
+
+        ITreeIndexFrameFactory interiorFrameFactory = new RTreeNSMInteriorFrameFactory(tupleWriterFactory,
+                keyFieldCount);
+        ITreeIndexFrameFactory leafFrameFactory = new RTreeNSMLeafFrameFactory(tupleWriterFactory, keyFieldCount);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
+
+        IRTreeFrame interiorFrame = (IRTreeFrame) interiorFrameFactory.createFrame();
+        IRTreeFrame leafFrame = (IRTreeFrame) leafFrameFactory.createFrame();
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
+
+        RTree rtree = new RTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        rtree.create(fileId, leafFrame, metaFrame);
+        rtree.open(fileId);
+
+        ByteBuffer hyracksFrame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
+
+        @SuppressWarnings("rawtypes")
+        ISerializerDeserializer[] recDescSers = { DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(hyracksFrame);
+        FrameTupleReference tuple = new FrameTupleReference();
+
+        RTreeOpContext insertOpCtx = rtree.createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
+
+        Random rnd = new Random();
+        rnd.setSeed(50);
+
+        for (int i = 0; i < 5000; i++) {
+
+            double p1x = rnd.nextDouble();
+            double p1y = rnd.nextDouble();
+            double p2x = rnd.nextDouble();
+            double p2y = rnd.nextDouble();
+
+            double pk1 = rnd.nextDouble();
+            int pk2 = rnd.nextInt();
+            double pk3 = rnd.nextDouble();
+
+            tb.reset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(pk1, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(pk2, dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(pk3, dos);
+            tb.addFieldEndOffset();
+
+            appender.reset(hyracksFrame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
+
+            tuple.reset(accessor, 0);
+
+            if (i % 1000 == 0) {
+                print("INSERTING " + i + " " + Math.min(p1x, p2x) + " " + Math.min(p1y, p2y) + " " + Math.max(p1x, p2x)
+                        + " " + Math.max(p1y, p2y) + "\n");
+            }
+
+            try {
+                rtree.insert(tuple, insertOpCtx);
+            } catch (TreeIndexException e) {
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+
+        // rtree.printTree(leafFrame, interiorFrame, recDescSers);
+        // System.err.println();
+
+        String rtreeStats = rtree.printStats();
+        print(rtreeStats);
+
+        RTreeOpContext deleteOpCtx = rtree.createOpContext(IndexOp.DELETE, leafFrame, interiorFrame, metaFrame);
+        rnd.setSeed(50);
+        for (int i = 0; i < 5000; i++) {
+
+            double p1x = rnd.nextDouble();
+            double p1y = rnd.nextDouble();
+            double p2x = rnd.nextDouble();
+            double p2y = rnd.nextDouble();
+
+            double pk1 = rnd.nextDouble();
+            int pk2 = rnd.nextInt();
+            double pk3 = rnd.nextDouble();
+
+            tb.reset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(pk1, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(pk2, dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(pk3, dos);
+            tb.addFieldEndOffset();
+
+            appender.reset(hyracksFrame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
+
+            tuple.reset(accessor, 0);
+
+            if (i % 1000 == 0) {
+                print("DELETING " + i + " " + Math.min(p1x, p2x) + " " + Math.min(p1y, p2y) + " " + Math.max(p1x, p2x)
+                        + " " + Math.max(p1y, p2y) + "\n");
+            }
+
+            try {
+                rtree.delete(tuple, deleteOpCtx);
+
+            } catch (TreeIndexException e) {
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+
+        TreeIndexStatsGatherer statsGatherer = new TreeIndexStatsGatherer(bufferCache, freePageManager, fileId,
+                rtree.getRootPageId());
+        TreeIndexStats stats = statsGatherer.gatherStats(leafFrame, interiorFrame, metaFrame);
+        String string = stats.toString();
+        System.err.println(string);
+
+        rtree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+
+    }
+
+    // create an R-tree of three dimensions
+    // fill the R-tree with random values using insertions
+    // perform ordered scan
+    @Test
+    public void test03() throws Exception {
+
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
+
+        // declare keys
+        int keyFieldCount = 6;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = DoubleBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        cmps[1] = cmps[0];
+        cmps[2] = cmps[0];
+        cmps[3] = cmps[0];
+        cmps[4] = cmps[0];
+        cmps[5] = cmps[0];
+
+        // declare tuple fields
+        int fieldCount = 9;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(8);
+        typeTraits[1] = new TypeTrait(8);
+        typeTraits[2] = new TypeTrait(8);
+        typeTraits[3] = new TypeTrait(8);
+        typeTraits[4] = new TypeTrait(8);
+        typeTraits[5] = new TypeTrait(8);
+        typeTraits[6] = new TypeTrait(8);
+        typeTraits[7] = new TypeTrait(4);
+        typeTraits[8] = new TypeTrait(8);
+
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+
+        RTreeTypeAwareTupleWriterFactory tupleWriterFactory = new RTreeTypeAwareTupleWriterFactory(typeTraits);
+
+        ITreeIndexFrameFactory interiorFrameFactory = new RTreeNSMInteriorFrameFactory(tupleWriterFactory,
+                keyFieldCount);
+        ITreeIndexFrameFactory leafFrameFactory = new RTreeNSMLeafFrameFactory(tupleWriterFactory, keyFieldCount);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
+
+        IRTreeFrame interiorFrame = (IRTreeFrame) interiorFrameFactory.createFrame();
+        IRTreeFrame leafFrame = (IRTreeFrame) leafFrameFactory.createFrame();
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
+
+        RTree rtree = new RTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        rtree.create(fileId, leafFrame, metaFrame);
+        rtree.open(fileId);
+
+        ByteBuffer hyracksFrame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
+
+        @SuppressWarnings("rawtypes")
+        ISerializerDeserializer[] recDescSers = { DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                IntegerSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(hyracksFrame);
+        FrameTupleReference tuple = new FrameTupleReference();
+
+        RTreeOpContext insertOpCtx = rtree.createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
+
+        Random rnd = new Random();
+        rnd.setSeed(50);
+
+        for (int i = 0; i < 5000; i++) {
+
+            double p1x = rnd.nextDouble();
+            double p1y = rnd.nextDouble();
+            double p1z = rnd.nextDouble();
+            double p2x = rnd.nextDouble();
+            double p2y = rnd.nextDouble();
+            double p2z = rnd.nextDouble();
+
+            double pk1 = rnd.nextDouble();
+            int pk2 = rnd.nextInt();
+            double pk3 = rnd.nextDouble();
+
+            tb.reset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1z, p2z), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1z, p2z), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(pk1, dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(pk2, dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(pk3, dos);
+            tb.addFieldEndOffset();
+
+            appender.reset(hyracksFrame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
+
+            tuple.reset(accessor, 0);
+
+            if (i % 1000 == 0) {
+                print("INSERTING " + i + " " + Math.min(p1x, p2x) + " " + Math.min(p1y, p2y) + " " + Math.min(p1z, p2z)
+                        + " " + " " + Math.max(p1x, p2x) + " " + Math.max(p1y, p2y) + " " + Math.max(p1z, p2z) + "\n");
+            }
+
+            try {
+                rtree.insert(tuple, insertOpCtx);
+            } catch (TreeIndexException e) {
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+
+        // rtree.printTree(leafFrame, interiorFrame, recDescSers);
+        // System.err.println();
+
+        String rtreeStats = rtree.printStats();
+        print(rtreeStats);
+
+        // disk-order scan
+        print("DISK-ORDER SCAN:\n");
+        TreeDiskOrderScanCursor diskOrderCursor = new TreeDiskOrderScanCursor(leafFrame);
+        RTreeOpContext diskOrderScanOpCtx = rtree.createOpContext(IndexOp.DISKORDERSCAN, leafFrame, null, null);
+        rtree.diskOrderScan(diskOrderCursor, leafFrame, metaFrame, diskOrderScanOpCtx);
+        try {
+            while (diskOrderCursor.hasNext()) {
+                diskOrderCursor.next();
+                ITupleReference frameTuple = diskOrderCursor.getTuple();
+                String rec = cmp.printTuple(frameTuple, recDescSers);
+                print(rec + "\n");
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            diskOrderCursor.close();
+        }
+
+        TreeIndexStatsGatherer statsGatherer = new TreeIndexStatsGatherer(bufferCache, freePageManager, fileId,
+                rtree.getRootPageId());
+        TreeIndexStats stats = statsGatherer.gatherStats(leafFrame, interiorFrame, metaFrame);
+        String string = stats.toString();
+        System.err.println(string);
+
+        rtree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+
+    }
+}
diff --git a/hyracks-tests/hyracks-storage-am-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/rtree/SearchCursorTest.java b/hyracks-tests/hyracks-storage-am-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/rtree/SearchCursorTest.java
new file mode 100644
index 0000000..3060765
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-am-rtree-test/src/test/java/edu/uci/ics/hyracks/storage/am/rtree/SearchCursorTest.java
@@ -0,0 +1,240 @@
+/*
+ * Copyright 2009-2010 by The Regents of the University of California
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * you may obtain a copy of the License from
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package edu.uci.ics.hyracks.storage.am.rtree;
+
+import java.io.ByteArrayInputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.io.DataOutput;
+import java.io.File;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Random;
+
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
+import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
+import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
+import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
+import edu.uci.ics.hyracks.api.dataflow.value.TypeTrait;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
+import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.FrameTupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.dataflow.common.data.comparators.DoubleBinaryComparatorFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.DoubleSerializerDeserializer;
+import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer;
+import edu.uci.ics.hyracks.storage.am.common.api.IFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexCursor;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrame;
+import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndexMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.api.TreeIndexException;
+import edu.uci.ics.hyracks.storage.am.common.frames.LIFOMetaDataFrameFactory;
+import edu.uci.ics.hyracks.storage.am.common.freepage.LinkedListFreePageManager;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOp;
+import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeInteriorFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.api.IRTreeLeafFrame;
+import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreeNSMInteriorFrameFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreeNSMLeafFrameFactory;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTree;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTreeOpContext;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.RTreeSearchCursor;
+import edu.uci.ics.hyracks.storage.am.rtree.impls.SearchPredicate;
+import edu.uci.ics.hyracks.storage.am.rtree.tuples.RTreeTypeAwareTupleWriterFactory;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
+import edu.uci.ics.hyracks.test.support.TestUtils;
+
+public class SearchCursorTest extends AbstractRTreeTest {
+    private static final int PAGE_SIZE = 256;
+    private static final int NUM_PAGES = 10;
+    private static final int MAX_OPEN_FILES = 10;
+    private static final int HYRACKS_FRAME_SIZE = 128;
+    private IHyracksStageletContext ctx = TestUtils.create(HYRACKS_FRAME_SIZE);
+
+    // create an R-tree of two dimensions
+    // fill the R-tree with random values using insertions
+    // and then perform range search
+    @Test
+    public void searchCursorTest() throws Exception {
+
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        bufferCache.openFile(fileId);
+
+        // declare keys
+        int keyFieldCount = 4;
+        IBinaryComparator[] cmps = new IBinaryComparator[keyFieldCount];
+        cmps[0] = DoubleBinaryComparatorFactory.INSTANCE.createBinaryComparator();
+        cmps[1] = cmps[0];
+        cmps[2] = cmps[0];
+        cmps[3] = cmps[0];
+
+        // declare tuple fields
+        int fieldCount = 5;
+        ITypeTrait[] typeTraits = new ITypeTrait[fieldCount];
+        typeTraits[0] = new TypeTrait(8);
+        typeTraits[1] = new TypeTrait(8);
+        typeTraits[2] = new TypeTrait(8);
+        typeTraits[3] = new TypeTrait(8);
+        typeTraits[4] = new TypeTrait(4);
+
+        MultiComparator cmp = new MultiComparator(typeTraits, cmps);
+
+        RTreeTypeAwareTupleWriterFactory tupleWriterFactory = new RTreeTypeAwareTupleWriterFactory(typeTraits);
+
+        ITreeIndexFrameFactory interiorFrameFactory = new RTreeNSMInteriorFrameFactory(tupleWriterFactory,
+                keyFieldCount);
+        ITreeIndexFrameFactory leafFrameFactory = new RTreeNSMLeafFrameFactory(tupleWriterFactory, keyFieldCount);
+        ITreeIndexMetaDataFrameFactory metaFrameFactory = new LIFOMetaDataFrameFactory();
+        ITreeIndexMetaDataFrame metaFrame = metaFrameFactory.createFrame();
+
+        IRTreeInteriorFrame interiorFrame = (IRTreeInteriorFrame) interiorFrameFactory.createFrame();
+        IRTreeLeafFrame leafFrame = (IRTreeLeafFrame) leafFrameFactory.createFrame();
+        IFreePageManager freePageManager = new LinkedListFreePageManager(bufferCache, fileId, 0, metaFrameFactory);
+
+        RTree rtree = new RTree(bufferCache, freePageManager, interiorFrameFactory, leafFrameFactory, cmp);
+        rtree.create(fileId, leafFrame, metaFrame);
+        rtree.open(fileId);
+
+        ByteBuffer hyracksFrame = ctx.allocateFrame();
+        FrameTupleAppender appender = new FrameTupleAppender(ctx.getFrameSize());
+        ArrayTupleBuilder tb = new ArrayTupleBuilder(cmp.getFieldCount());
+        DataOutput dos = tb.getDataOutput();
+
+        @SuppressWarnings("rawtypes")
+        ISerializerDeserializer[] recDescSers = { DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, DoubleSerializerDeserializer.INSTANCE,
+                DoubleSerializerDeserializer.INSTANCE, IntegerSerializerDeserializer.INSTANCE };
+        RecordDescriptor recDesc = new RecordDescriptor(recDescSers);
+        IFrameTupleAccessor accessor = new FrameTupleAccessor(ctx.getFrameSize(), recDesc);
+        accessor.reset(hyracksFrame);
+        FrameTupleReference tuple = new FrameTupleReference();
+
+        RTreeOpContext insertOpCtx = rtree.createOpContext(IndexOp.INSERT, leafFrame, interiorFrame, metaFrame);
+
+        Random rnd = new Random();
+        rnd.setSeed(50);
+        for (int i = 0; i < 5000; i++) {
+
+            double p1x = rnd.nextDouble();
+            double p1y = rnd.nextDouble();
+            double p2x = rnd.nextDouble();
+            double p2y = rnd.nextDouble();
+
+            int pk = rnd.nextInt();
+
+            tb.reset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(pk, dos);
+            tb.addFieldEndOffset();
+
+            appender.reset(hyracksFrame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
+
+            tuple.reset(accessor, 0);
+
+            if (i % 1000 == 0) {
+                print("INSERTING " + i + " " + Math.min(p1x, p2x) + " " + Math.min(p1y, p2y) + " " + Math.max(p1x, p2x)
+                        + " " + Math.max(p1y, p2y) + "\n");
+            }
+
+            try {
+                rtree.insert(tuple, insertOpCtx);
+            } catch (TreeIndexException e) {
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+
+        for (int i = 0; i < 50; i++) {
+            double p1x = rnd.nextDouble();
+            double p1y = rnd.nextDouble();
+            double p2x = rnd.nextDouble();
+            double p2y = rnd.nextDouble();
+
+            int pk = rnd.nextInt();
+
+            tb.reset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.min(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1x, p2x), dos);
+            tb.addFieldEndOffset();
+            DoubleSerializerDeserializer.INSTANCE.serialize(Math.max(p1y, p2y), dos);
+            tb.addFieldEndOffset();
+            IntegerSerializerDeserializer.INSTANCE.serialize(pk, dos);
+            tb.addFieldEndOffset();
+
+            appender.reset(hyracksFrame, true);
+            appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize());
+
+            tuple.reset(accessor, 0);
+
+            print(i + " Searching for: " + Math.min(p1x, p2x) + " " + Math.min(p1y, p2y) + " " + Math.max(p1x, p2x)
+                    + " " + Math.max(p1y, p2y) + "\n");
+
+            ITreeIndexCursor searchCursor = new RTreeSearchCursor(interiorFrame, leafFrame);
+            SearchPredicate searchPredicate = new SearchPredicate(tuple, cmp);
+
+            RTreeOpContext searchOpCtx = rtree.createOpContext(IndexOp.SEARCH, leafFrame, interiorFrame, metaFrame);
+            rtree.search(searchCursor, searchPredicate, searchOpCtx);
+
+            ArrayList<Integer> results = new ArrayList<Integer>();
+            try {
+                while (searchCursor.hasNext()) {
+                    searchCursor.next();
+                    ITupleReference frameTuple = searchCursor.getTuple();
+                    ByteArrayInputStream inStream = new ByteArrayInputStream(frameTuple.getFieldData(4),
+                            frameTuple.getFieldStart(4), frameTuple.getFieldLength(4));
+                    DataInput dataIn = new DataInputStream(inStream);
+                    Integer res = IntegerSerializerDeserializer.INSTANCE.deserialize(dataIn);
+                    results.add(res);
+                }
+            } catch (Exception e) {
+                e.printStackTrace();
+            } finally {
+                searchCursor.close();
+            }
+
+            System.err.println("There are " + results.size() + " objects that satisfy the query");
+        }
+
+        rtree.close();
+        bufferCache.closeFile(fileId);
+        bufferCache.close();
+    }
+}
diff --git a/hyracks-tests/hyracks-storage-common-test/pom.xml b/hyracks-tests/hyracks-storage-common-test/pom.xml
new file mode 100644
index 0000000..1468c78
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-common-test/pom.xml
@@ -0,0 +1,54 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>edu.uci.ics.hyracks</groupId>
+  <artifactId>hyracks-storage-common-test</artifactId>
+  <version>0.1.7-SNAPSHOT</version>
+
+  <parent>
+    <groupId>edu.uci.ics.hyracks</groupId>
+    <artifactId>hyracks-tests</artifactId>
+    <version>0.1.7-SNAPSHOT</version>
+  </parent>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>2.0.2</version>
+        <configuration>
+          <source>1.6</source>
+          <target>1.6</target>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+  <dependencies>
+  	<dependency>
+  		<groupId>junit</groupId>
+  		<artifactId>junit</artifactId>
+  		<version>4.8.1</version>
+  		<type>jar</type>
+  		<scope>test</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-control-nc</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<scope>compile</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-storage-common</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<scope>compile</scope>
+  	</dependency>
+  	<dependency>
+  		<groupId>edu.uci.ics.hyracks</groupId>
+  		<artifactId>hyracks-test-support</artifactId>
+  		<version>0.1.7-SNAPSHOT</version>
+  		<type>jar</type>
+  		<scope>test</scope>
+  	</dependency>
+  </dependencies>
+</project>
diff --git a/hyracks-tests/hyracks-storage-common-test/src/test/java/edu/uci/ics/hyracks/storage/common/BufferCacheTest.java b/hyracks-tests/hyracks-storage-common-test/src/test/java/edu/uci/ics/hyracks/storage/common/BufferCacheTest.java
new file mode 100644
index 0000000..680fd3b
--- /dev/null
+++ b/hyracks-tests/hyracks-storage-common-test/src/test/java/edu/uci/ics/hyracks/storage/common/BufferCacheTest.java
@@ -0,0 +1,311 @@
+package edu.uci.ics.hyracks.storage.common;
+
+import java.io.File;
+import java.text.SimpleDateFormat;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Random;
+
+import org.junit.AfterClass;
+import org.junit.Assert;
+import org.junit.Test;
+
+import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.api.io.FileReference;
+import edu.uci.ics.hyracks.storage.common.buffercache.IBufferCache;
+import edu.uci.ics.hyracks.storage.common.buffercache.ICachedPage;
+import edu.uci.ics.hyracks.storage.common.file.BufferedFileHandle;
+import edu.uci.ics.hyracks.storage.common.file.IFileMapProvider;
+import edu.uci.ics.hyracks.test.support.TestStorageManagerComponentHolder;
+import edu.uci.ics.hyracks.test.support.TestUtils;
+
+public class BufferCacheTest {
+    protected static final List<String> openedFiles = new ArrayList<String>();    
+    protected static final SimpleDateFormat simpleDateFormat = new SimpleDateFormat("ddMMyy-hhmmssSS");
+    protected static final String tmpDir = System.getProperty("java.io.tmpdir");
+    protected static final String sep = System.getProperty("file.separator");    
+    
+    private static final int PAGE_SIZE = 256;
+    private static final int NUM_PAGES = 10;
+    private static final int MAX_OPEN_FILES = 20;
+    private static final int HYRACKS_FRAME_SIZE = PAGE_SIZE;
+    private IHyracksStageletContext ctx = TestUtils.create(HYRACKS_FRAME_SIZE);
+    
+    private static final Random rnd = new Random(50);
+    
+    private String getFileName() {
+        String fileName = tmpDir + sep + simpleDateFormat.format(new Date()) + openedFiles.size();
+        openedFiles.add(fileName);
+        return fileName;
+    }          
+    
+    @Test
+    public void simpleOpenPinCloseTest() throws HyracksDataException {
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        String fileName = getFileName();
+        FileReference file = new FileReference(new File(fileName));
+        bufferCache.createFile(file);
+        int fileId = fmp.lookupFileId(file);
+        int num = 10;
+        int testPageId = 0;
+        
+        bufferCache.openFile(fileId);
+        
+        ICachedPage page = null;
+        
+        // tryPin should fail
+        page = bufferCache.tryPin(BufferedFileHandle.getDiskPageId(fileId, testPageId));
+        Assert.assertNull(page);
+        
+        // pin page should succeed
+        page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, testPageId), true);
+        page.acquireWriteLatch();
+        try {            
+            for(int i = 0; i < num; i++) {
+                page.getBuffer().putInt(i * 4, i);
+            }               
+            
+            // try pin should succeed         
+            ICachedPage page2 = bufferCache.tryPin(BufferedFileHandle.getDiskPageId(fileId, testPageId));
+            Assert.assertNotNull(page2);
+            bufferCache.unpin(page2);
+            
+        } finally {
+            page.releaseWriteLatch();
+            bufferCache.unpin(page);
+        }                        
+        
+        bufferCache.closeFile(fileId);
+        
+        boolean exceptionThrown = false;
+        
+        // tryPin should fail since file is not open
+        try {
+            page = bufferCache.tryPin(BufferedFileHandle.getDiskPageId(fileId, testPageId));
+        } catch(HyracksDataException e) {
+            exceptionThrown = true;
+        }
+        Assert.assertTrue(exceptionThrown);
+        
+        // pin should fail since file is not open
+        exceptionThrown = false;
+        try {
+            page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, testPageId), false);
+        } catch(HyracksDataException e) {
+            exceptionThrown = true;
+        }
+        Assert.assertTrue(exceptionThrown);
+        
+        
+        // open file again
+        bufferCache.openFile(fileId);
+        
+        // tryPin should succeed because page should still be cached        
+        page = bufferCache.tryPin(BufferedFileHandle.getDiskPageId(fileId, testPageId));        
+        Assert.assertNotNull(page);
+        page.acquireReadLatch();
+        try {
+            // verify contents of page
+            for(int i = 0; i < num; i++) {
+                Assert.assertEquals(page.getBuffer().getInt(i * 4), i);
+            }
+        } finally {
+            page.releaseReadLatch();
+            bufferCache.unpin(page);
+        }                
+        
+        bufferCache.closeFile(fileId);        
+        bufferCache.close();
+    }
+        
+    @Test
+    public void simpleMaxOpenFilesTest() throws HyracksDataException {
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        
+        List<Integer> fileIds = new ArrayList<Integer>();
+        
+        for(int i = 0; i < MAX_OPEN_FILES; i++) {
+            String fileName = getFileName();
+            FileReference file = new FileReference(new File(fileName));
+            bufferCache.createFile(file);
+            int fileId = fmp.lookupFileId(file);
+            bufferCache.openFile(fileId);
+            fileIds.add(fileId);
+        }
+        
+        boolean exceptionThrown = false;
+        
+        // since all files are open, next open should fail
+        try {
+            String fileName = getFileName();
+            FileReference file = new FileReference(new File(fileName));
+            bufferCache.createFile(file);
+            int fileId = fmp.lookupFileId(file);
+            bufferCache.openFile(fileId);
+        } catch(HyracksDataException e) {
+            exceptionThrown = true;
+        }
+        Assert.assertTrue(exceptionThrown);
+        
+        // close a random file
+        int ix = Math.abs(rnd.nextInt()) % fileIds.size();
+        bufferCache.closeFile(fileIds.get(ix));
+        fileIds.remove(ix);
+        
+        // now open should succeed again
+        exceptionThrown = false;
+        try {
+            String fileName = getFileName();
+            FileReference file = new FileReference(new File(fileName));
+            bufferCache.createFile(file);
+            int fileId = fmp.lookupFileId(file);
+            bufferCache.openFile(fileId);
+            fileIds.add(fileId);
+            
+        } catch(HyracksDataException e) {
+            exceptionThrown = true;
+        }
+        Assert.assertFalse(exceptionThrown);
+        
+        for(Integer i : fileIds) {
+            bufferCache.closeFile(i.intValue());
+        }
+        
+        bufferCache.close();
+    }
+    
+    @Test
+    public void contentCheckingMaxOpenFilesTest() throws HyracksDataException {
+        TestStorageManagerComponentHolder.init(PAGE_SIZE, NUM_PAGES, MAX_OPEN_FILES);
+        IBufferCache bufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
+        IFileMapProvider fmp = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
+        
+        List<Integer> fileIds = new ArrayList<Integer>();
+        Map<Integer, ArrayList<Integer>> pageContents = new HashMap<Integer, ArrayList<Integer>>();        
+        int num = 10;
+        int testPageId = 0;        
+        
+        // open max number of files and write some stuff into their first page
+        for(int i = 0; i < MAX_OPEN_FILES; i++) {
+            String fileName = getFileName();
+            FileReference file = new FileReference(new File(fileName));
+            bufferCache.createFile(file);
+            int fileId = fmp.lookupFileId(file);
+            bufferCache.openFile(fileId);
+            fileIds.add(fileId);
+            
+            ICachedPage page = null;            
+            page = bufferCache.pin(BufferedFileHandle.getDiskPageId(fileId, testPageId), true);
+            page.acquireWriteLatch();
+            try {            
+                ArrayList<Integer> values = new ArrayList<Integer>();                
+                for(int j = 0; j < num; j++) {
+                    int x = Math.abs(rnd.nextInt());
+                    page.getBuffer().putInt(j * 4, x);
+                    values.add(x);
+                }
+                pageContents.put(fileId, values);                
+            } finally {
+                page.releaseWriteLatch();
+                bufferCache.unpin(page);
+            }            
+        }        
+        
+        boolean exceptionThrown = false;
+        
+        // since all files are open, next open should fail
+        try {
+            String fileName = getFileName();
+            FileReference file = new FileReference(new File(fileName));
+            bufferCache.createFile(file);
+            int fileId = fmp.lookupFileId(file);
+            bufferCache.openFile(fileId);
+        } catch(HyracksDataException e) {
+            exceptionThrown = true;
+        }
+        Assert.assertTrue(exceptionThrown);        
+        
+        // close a few random files
+        ArrayList<Integer> closedFileIds = new ArrayList<Integer>();
+        int filesToClose = 5;
+        for(int i = 0; i < filesToClose; i++) {
+            int ix = Math.abs(rnd.nextInt()) % fileIds.size();            
+            bufferCache.closeFile(fileIds.get(ix));
+            closedFileIds.add(fileIds.get(ix));
+            fileIds.remove(ix);
+        }        
+        
+        // now open a few new files
+        for(int i = 0; i < filesToClose; i++) {
+            String fileName = getFileName();
+            FileReference file = new FileReference(new File(fileName));
+            bufferCache.createFile(file);
+            int fileId = fmp.lookupFileId(file);
+            bufferCache.openFile(fileId);
+            fileIds.add(fileId);
+        }        
+        
+        // since all files are open, next open should fail
+        try {
+            String fileName = getFileName();
+            FileReference file = new FileReference(new File(fileName));
+            bufferCache.createFile(file);
+            int fileId = fmp.lookupFileId(file);
+            bufferCache.openFile(fileId);            
+        } catch(HyracksDataException e) {
+            exceptionThrown = true;
+        }
+        Assert.assertTrue(exceptionThrown);       
+        
+        // close a few random files again        
+        for(int i = 0; i < filesToClose; i++) {
+            int ix = Math.abs(rnd.nextInt()) % fileIds.size();            
+            bufferCache.closeFile(fileIds.get(ix));
+            closedFileIds.add(fileIds.get(ix));
+            fileIds.remove(ix);
+        }
+        
+        // now open those closed files again and verify their contents
+        for(int i = 0; i < filesToClose; i++) {
+            int closedFileId = closedFileIds.get(i);
+            bufferCache.openFile(closedFileId);
+            fileIds.add(closedFileId);
+            
+            // pin first page and verify contents
+            ICachedPage page = null;            
+            page = bufferCache.pin(BufferedFileHandle.getDiskPageId(closedFileId, testPageId), false);
+            page.acquireReadLatch();
+            try {            
+                ArrayList<Integer> values = pageContents.get(closedFileId);                
+                for(int j = 0; j < values.size(); j++) {
+                    Assert.assertEquals(values.get(j).intValue(), page.getBuffer().getInt(j * 4));                    
+                }      
+            } finally {
+                page.releaseReadLatch();
+                bufferCache.unpin(page);
+            }            
+        }         
+        
+        for(Integer i : fileIds) {
+            bufferCache.closeFile(i.intValue());
+        }
+        
+        bufferCache.close();
+    }
+    
+    @AfterClass
+    public static void cleanup() throws Exception {
+        for(String s : openedFiles) {
+            File f = new File(s);
+            f.deleteOnExit();
+        }
+    }
+}
diff --git a/hyracks-tests/pom.xml b/hyracks-tests/pom.xml
index 4a391bc..ee1280d 100644
--- a/hyracks-tests/pom.xml
+++ b/hyracks-tests/pom.xml
@@ -12,7 +12,9 @@
   </parent>
 
   <modules>
+    <module>hyracks-storage-common-test</module>
     <module>hyracks-storage-am-btree-test</module>
     <module>hyracks-storage-am-invertedindex-test</module>
+    <module>hyracks-storage-am-rtree-test</module>
   </modules>
 </project>
diff --git a/pom.xml b/pom.xml
index b6cc875..e9ccdd0 100644
--- a/pom.xml
+++ b/pom.xml
@@ -71,8 +71,10 @@
     <module>hyracks-control-nc</module>
     <module>hyracks-cli</module>
     <module>hyracks-storage-common</module>
+    <module>hyracks-storage-am-common</module>
     <module>hyracks-storage-am-btree</module>
     <module>hyracks-storage-am-invertedindex</module>
+    <module>hyracks-storage-am-rtree</module>
     <module>hyracks-test-support</module>
     <module>hyracks-tests</module>
     <module>hyracks-server</module>