diff --git a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AInt32AscNormalizedKeyComputerFactory.java b/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AInt32AscNormalizedKeyComputerFactory.java
deleted file mode 100644
index 903ac3d..0000000
--- a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AInt32AscNormalizedKeyComputerFactory.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers;
-
-import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputer;
-import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
-import edu.uci.ics.hyracks.dataflow.common.data.normalizers.IntegerNormalizedKeyComputerFactory;
-
-public class AInt32AscNormalizedKeyComputerFactory implements INormalizedKeyComputerFactory {
-
-    private static final long serialVersionUID = 1L;
-
-    public static final AInt32AscNormalizedKeyComputerFactory INSTANCE = new AInt32AscNormalizedKeyComputerFactory();
-
-    private IntegerNormalizedKeyComputerFactory inkcf = new IntegerNormalizedKeyComputerFactory();
-
-    private AInt32AscNormalizedKeyComputerFactory() {
-    }
-
-    @Override
-    public INormalizedKeyComputer createNormalizedKeyComputer() {
-        final INormalizedKeyComputer intNkc = inkcf.createNormalizedKeyComputer();
-        return new INormalizedKeyComputer() {
-
-            @Override
-            public int normalize(byte[] bytes, int start, int length) {
-                return intNkc.normalize(bytes, start + 1, length - 1);
-            }
-        };
-    }
-
-}
diff --git a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AInt32DescNormalizedKeyComputerFactory.java b/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AInt32DescNormalizedKeyComputerFactory.java
deleted file mode 100644
index cec6a40..0000000
--- a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AInt32DescNormalizedKeyComputerFactory.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers;
-
-import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputer;
-import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
-import edu.uci.ics.hyracks.dataflow.common.data.normalizers.IntegerNormalizedKeyComputerFactory;
-
-public class AInt32DescNormalizedKeyComputerFactory implements INormalizedKeyComputerFactory {
-
-    private static final long serialVersionUID = 1L;
-
-    public static final AInt32DescNormalizedKeyComputerFactory INSTANCE = new AInt32DescNormalizedKeyComputerFactory();
-
-    private IntegerNormalizedKeyComputerFactory inkcf = new IntegerNormalizedKeyComputerFactory();
-
-    private AInt32DescNormalizedKeyComputerFactory() {
-    }
-
-    @Override
-    public INormalizedKeyComputer createNormalizedKeyComputer() {
-        final INormalizedKeyComputer intNkc = inkcf.createNormalizedKeyComputer();
-        return new INormalizedKeyComputer() {
-
-            @Override
-            public int normalize(byte[] bytes, int start, int length) {
-                int nk = intNkc.normalize(bytes, start + 1, length - 1);
-                return (int) ((long) 0xffffffff - (long) nk);
-            }
-        };
-    }
-}
diff --git a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AStringAscNormalizedKeyComputerFactory.java b/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AStringAscNormalizedKeyComputerFactory.java
deleted file mode 100644
index 0d1780f..0000000
--- a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AStringAscNormalizedKeyComputerFactory.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers;
-
-import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputer;
-import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
-import edu.uci.ics.hyracks.dataflow.common.data.normalizers.UTF8StringNormalizedKeyComputerFactory;
-
-public class AStringAscNormalizedKeyComputerFactory implements INormalizedKeyComputerFactory {
-
-    private static final long serialVersionUID = 1L;
-
-    public static final AStringAscNormalizedKeyComputerFactory INSTANCE = new AStringAscNormalizedKeyComputerFactory();
-
-    private AStringAscNormalizedKeyComputerFactory() {
-    }
-
-    private UTF8StringNormalizedKeyComputerFactory strnkcf = new UTF8StringNormalizedKeyComputerFactory();
-
-    @Override
-    public INormalizedKeyComputer createNormalizedKeyComputer() {
-        final INormalizedKeyComputer strNkc = strnkcf.createNormalizedKeyComputer();
-        return new INormalizedKeyComputer() {
-
-            @Override
-            public int normalize(byte[] bytes, int start, int length) {
-                return strNkc.normalize(bytes, start + 1, length - 1);
-            }
-        };
-    }
-
-}
diff --git a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AStringDescNormalizedKeyComputerFactory.java b/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AStringDescNormalizedKeyComputerFactory.java
deleted file mode 100644
index 0ff6acd..0000000
--- a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AStringDescNormalizedKeyComputerFactory.java
+++ /dev/null
@@ -1,31 +0,0 @@
-package edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers;
-
-import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputer;
-import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
-import edu.uci.ics.hyracks.dataflow.common.data.normalizers.UTF8StringNormalizedKeyComputerFactory;
-
-public class AStringDescNormalizedKeyComputerFactory implements INormalizedKeyComputerFactory {
-
-    private static final long serialVersionUID = 1L;
-
-    public static final AStringDescNormalizedKeyComputerFactory INSTANCE = new AStringDescNormalizedKeyComputerFactory();
-
-    private AStringDescNormalizedKeyComputerFactory() {
-    }
-
-    private UTF8StringNormalizedKeyComputerFactory strnkcf = new UTF8StringNormalizedKeyComputerFactory();
-
-    @Override
-    public INormalizedKeyComputer createNormalizedKeyComputer() {
-        final INormalizedKeyComputer strNkc = strnkcf.createNormalizedKeyComputer();
-        return new INormalizedKeyComputer() {
-
-            @Override
-            public int normalize(byte[] bytes, int start, int length) {
-                int nk = strNkc.normalize(bytes, start + 1, length - 1);
-                return (int) ((long) 0xffffffff - (long) nk);
-            }
-        };
-    }
-
-}
diff --git a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AWrappedAscNormalizedKeyComputerFactory.java b/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AWrappedAscNormalizedKeyComputerFactory.java
new file mode 100644
index 0000000..2efa593
--- /dev/null
+++ b/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AWrappedAscNormalizedKeyComputerFactory.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.asterix.dataflow.data.nontagged.keynormalizers;
+
+import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputer;
+import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
+
+/**
+ * This class uses a decorator pattern to wrap an ASC ordered INomralizedKeyComputerFactory implementation to
+ * obtain the ASC order.
+ */
+public class AWrappedAscNormalizedKeyComputerFactory implements INormalizedKeyComputerFactory {
+
+    private static final long serialVersionUID = 1L;
+    private final INormalizedKeyComputerFactory nkcf;
+
+    public AWrappedAscNormalizedKeyComputerFactory(INormalizedKeyComputerFactory nkcf) {
+        this.nkcf = nkcf;
+    }
+
+    @Override
+    public INormalizedKeyComputer createNormalizedKeyComputer() {
+        final INormalizedKeyComputer nkc = nkcf.createNormalizedKeyComputer();
+        return new INormalizedKeyComputer() {
+
+            @Override
+            public int normalize(byte[] bytes, int start, int length) {
+                // start +1, length -1 is because in ASTERIX data format, there is always a type tag before the value 
+                return nkc.normalize(bytes, start + 1, length - 1);
+            }
+        };
+    }
+
+}
diff --git a/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AWrappedDescNormalizedKeyComputerFactory.java b/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AWrappedDescNormalizedKeyComputerFactory.java
new file mode 100644
index 0000000..a5653b9
--- /dev/null
+++ b/asterix-om/src/main/java/edu/uci/ics/asterix/dataflow/data/nontagged/keynormalizers/AWrappedDescNormalizedKeyComputerFactory.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.asterix.dataflow.data.nontagged.keynormalizers;
+
+import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputer;
+import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
+
+/**
+ * This class uses a decorator pattern to wrap an ASC ordered INomralizedKeyComputerFactory implementation
+ * to obtain the DESC order.
+ */
+public class AWrappedDescNormalizedKeyComputerFactory implements INormalizedKeyComputerFactory {
+
+    private static final long serialVersionUID = 1L;
+    private final INormalizedKeyComputerFactory nkcf;
+
+    public AWrappedDescNormalizedKeyComputerFactory(INormalizedKeyComputerFactory nkcf) {
+        this.nkcf = nkcf;
+    }
+
+    @Override
+    public INormalizedKeyComputer createNormalizedKeyComputer() {
+        final INormalizedKeyComputer nkc = nkcf.createNormalizedKeyComputer();
+        return new INormalizedKeyComputer() {
+
+            @Override
+            public int normalize(byte[] bytes, int start, int length) {
+                int key = nkc.normalize(bytes, start + 1, length - 1);
+                return (int) ((long) 0xffffffff - (long) key);
+            }
+        };
+    }
+
+}
diff --git a/asterix-om/src/main/java/edu/uci/ics/asterix/formats/nontagged/AqlNormalizedKeyComputerFactoryProvider.java b/asterix-om/src/main/java/edu/uci/ics/asterix/formats/nontagged/AqlNormalizedKeyComputerFactoryProvider.java
index fe953dc..23306ed 100644
--- a/asterix-om/src/main/java/edu/uci/ics/asterix/formats/nontagged/AqlNormalizedKeyComputerFactoryProvider.java
+++ b/asterix-om/src/main/java/edu/uci/ics/asterix/formats/nontagged/AqlNormalizedKeyComputerFactoryProvider.java
@@ -1,12 +1,15 @@
 package edu.uci.ics.asterix.formats.nontagged;
 
-import edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers.AInt32AscNormalizedKeyComputerFactory;
-import edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers.AInt32DescNormalizedKeyComputerFactory;
-import edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers.AStringAscNormalizedKeyComputerFactory;
-import edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers.AStringDescNormalizedKeyComputerFactory;
+import edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers.AWrappedAscNormalizedKeyComputerFactory;
+import edu.uci.ics.asterix.dataflow.data.nontagged.keynormalizers.AWrappedDescNormalizedKeyComputerFactory;
 import edu.uci.ics.asterix.om.types.IAType;
 import edu.uci.ics.hyracks.algebricks.data.INormalizedKeyComputerFactoryProvider;
 import edu.uci.ics.hyracks.api.dataflow.value.INormalizedKeyComputerFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.normalizers.DoubleNormalizedKeyComputerFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.normalizers.FloatNormalizedKeyComputerFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.normalizers.Integer64NormalizedKeyComputerFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.normalizers.IntegerNormalizedKeyComputerFactory;
+import edu.uci.ics.hyracks.dataflow.common.data.normalizers.UTF8StringNormalizedKeyComputerFactory;
 
 public class AqlNormalizedKeyComputerFactoryProvider implements INormalizedKeyComputerFactoryProvider {
 
@@ -21,10 +24,19 @@
         if (ascending) {
             switch (aqlType.getTypeTag()) {
                 case INT32: {
-                    return AInt32AscNormalizedKeyComputerFactory.INSTANCE;
+                    return new AWrappedAscNormalizedKeyComputerFactory(new IntegerNormalizedKeyComputerFactory());
+                }
+                case INT64: {
+                    return new AWrappedAscNormalizedKeyComputerFactory(new Integer64NormalizedKeyComputerFactory());
+                }
+                case FLOAT: {
+                    return new AWrappedAscNormalizedKeyComputerFactory(new FloatNormalizedKeyComputerFactory());
+                }
+                case DOUBLE: {
+                    return new AWrappedAscNormalizedKeyComputerFactory(new DoubleNormalizedKeyComputerFactory());
                 }
                 case STRING: {
-                    return AStringAscNormalizedKeyComputerFactory.INSTANCE;
+                    return new AWrappedAscNormalizedKeyComputerFactory(new UTF8StringNormalizedKeyComputerFactory());
                 }
                 default: {
                     return null;
@@ -33,10 +45,19 @@
         } else {
             switch (aqlType.getTypeTag()) {
                 case INT32: {
-                    return AInt32DescNormalizedKeyComputerFactory.INSTANCE;
+                    return new AWrappedDescNormalizedKeyComputerFactory(new IntegerNormalizedKeyComputerFactory());
+                }
+                case INT64: {
+                    return new AWrappedDescNormalizedKeyComputerFactory(new Integer64NormalizedKeyComputerFactory());
+                }
+                case FLOAT: {
+                    return new AWrappedDescNormalizedKeyComputerFactory(new FloatNormalizedKeyComputerFactory());
+                }
+                case DOUBLE: {
+                    return new AWrappedDescNormalizedKeyComputerFactory(new DoubleNormalizedKeyComputerFactory());
                 }
                 case STRING: {
-                    return AStringDescNormalizedKeyComputerFactory.INSTANCE;
+                    return new AWrappedDescNormalizedKeyComputerFactory(new UTF8StringNormalizedKeyComputerFactory());
                 }
                 default: {
                     return null;
@@ -44,5 +65,4 @@
             }
         }
     }
-
 }