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 3802710..c2dd1f4 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
@@ -21,4 +21,6 @@
 	
 	public void setPrevLeaf(int prevPage);
 	public int getPrevLeaf();
+	
+	public IBTreeTupleReference createTupleReference();
 }
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java
index 4e82bed..bbeb6a6 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/api/IBTreeTupleReference.java
@@ -5,7 +5,8 @@
 import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
 
 public interface IBTreeTupleReference extends ITupleReference {
-	public void setFieldCount(int fieldCount);	
+	public void setFieldCount(int fieldCount);
+	public void setFieldCount(int fieldStartIndex, int fieldCount);
 	public void resetByOffset(ByteBuffer buf, int tupleStartOffset);
 	public void resetByTupleIndex(IBTreeFrame frame, int tupleIndex);
 }
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 953152e..ecc177d 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
@@ -129,9 +129,7 @@
         else {
             newPrefixSlots = new int[totalSlotsNeeded];
         }
-        
-        //System.out.println("TOTALPREFIXBYTES: " + totalPrefixBytes);
-        
+                
         int[] newTupleSlots = new int[tupleCount];
         
         // WARNING: our hope is that compression is infrequent
@@ -149,16 +147,16 @@
         int prefixTupleIndex = 0;
         uncompressedTupleCount = 0;
         
-        TypeAwareTupleWriter tupleWriter = new TypeAwareTupleWriter(typeTraits);
+        TypeAwareTupleWriter tupleWriter = new TypeAwareTupleWriter(typeTraits);   
         
         FieldPrefixTupleReference tupleToWrite = new FieldPrefixTupleReference(tupleWriter.createTupleReference());
         tupleToWrite.setFieldCount(fieldCount);                
         
         while(tupleIndex < tupleCount) {           
-            if(kpIndex < keyPartitions.size()) {
+            if(kpIndex < keyPartitions.size()) {            	
             	
             	// beginning of keyPartition found, compress entire keyPartition
-            	if(tupleIndex == keyPartitions.get(kpIndex).firstTupleIndex) {            		
+            	if(tupleIndex == keyPartitions.get(kpIndex).firstTupleIndex) {            		            		
             		
             		// number of fields we decided to use for compression of this keyPartition
             		int numFieldsToCompress = keyPartitions.get(kpIndex).maxPmiIndex + 1;            		
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/FieldPrefixNSMLeafFrame.java
index ee77467..7642638 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/FieldPrefixNSMLeafFrame.java
@@ -28,6 +28,7 @@
 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;
@@ -318,7 +319,7 @@
 		frameTuple.setFieldCount(fields.length);
 		for(int i = 0; i < tupleCount; i++) {						
 			frameTuple.resetByTupleIndex(this, i);												
-			for(int j = 0; j < cmp.getKeyFieldCount(); j++) {
+			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);
@@ -532,7 +533,7 @@
 		// compact both pages		
 		compact(cmp);		
 		rightFrame.compact(cmp);
-		
+				
 		// insert last key
 		targetFrame.insert(tuple, cmp);
 				
@@ -540,9 +541,10 @@
 		frameTuple.resetByTupleIndex(this, getTupleCount()-1);
 		
 		int splitKeySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
-		splitKey.initData(splitKeySize);
+		splitKey.initData(splitKeySize);		
 		tupleWriter.writeTupleFields(frameTuple, 0, cmp.getKeyFieldCount(), splitKey.getBuffer(), 0);
-				
+		splitKey.getTuple().resetByOffset(splitKey.getBuffer(), 0);	
+		
 		return 0;
     }
     
@@ -601,4 +603,9 @@
 	public IBTreeTupleWriter getTupleWriter() {
     	return tupleWriter;
     }
+	
+	@Override
+	public IBTreeTupleReference createTupleReference() {
+		return new FieldPrefixTupleReference(tupleWriter.createTupleReference());
+	}
 }
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/NSMLeafFrame.java
index 363ab23..0fa8c2d 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/NSMLeafFrame.java
@@ -20,6 +20,7 @@
 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.FindSlotMode;
@@ -155,9 +156,9 @@
 		
 		int splitKeySize = tupleWriter.bytesRequired(frameTuple, 0, cmp.getKeyFieldCount());
 		splitKey.initData(splitKeySize);				
-		tupleWriter.writeTupleFields(frameTuple, 0, cmp.getKeyFieldCount(), splitKey.getBuffer(), 0);
+		tupleWriter.writeTupleFields(frameTuple, 0, cmp.getKeyFieldCount(), splitKey.getBuffer(), 0);		
+		splitKey.getTuple().resetByOffset(splitKey.getBuffer(), 0);
 		
-		splitKey.getTuple().resetByOffset(splitKey.getBuffer(), 0);				
 		return 0;
 	}
 
@@ -166,4 +167,9 @@
 		buf.putInt(freeSpaceOff, nextLeafOff + 4);
 		buf.putInt(totalFreeSpaceOff, buf.capacity() - (nextLeafOff + 4));
 	}
+	
+	@Override
+	public IBTreeTupleReference createTupleReference() {
+		return tupleWriter.createTupleReference();
+	}
 }
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 a4effb7..3bfc826 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
@@ -585,6 +585,7 @@
     			usefulCompression++;    			
     		}
     		else {
+    			
     			uselessCompressionTime += (end - start);    			    			    			
     			uselessCompression++;
     			
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 ba17ce7..d818e0a 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
@@ -46,6 +46,11 @@
 	}
 
 	@Override
+	public void setFieldCount(int fieldStartIndex, int fieldCount) {
+		// not implemented
+	}
+	
+	@Override
 	public int getFieldCount() {		
 		return fieldCount;
 	}
@@ -63,7 +68,7 @@
 			return helperTuple.getFieldLength(fIdx);
 		}
 		else {
-			helperTuple.setFieldCount(fieldCount - numPrefixFields);
+			helperTuple.setFieldCount(numPrefixFields, fieldCount - numPrefixFields);
 			helperTuple.resetByOffset(frame.getBuffer(), suffixTupleStartOff);
 			return helperTuple.getFieldLength(fIdx - numPrefixFields);
 		}				
@@ -77,7 +82,7 @@
 			return helperTuple.getFieldStart(fIdx);
 		}
 		else {
-			helperTuple.setFieldCount(fieldCount - numPrefixFields);
+			helperTuple.setFieldCount(numPrefixFields, fieldCount - numPrefixFields);
 			helperTuple.resetByOffset(frame.getBuffer(), suffixTupleStartOff);
 			return helperTuple.getFieldStart(fIdx - numPrefixFields);
 		}
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/RangeSearchCursor.java
index b451046..9970114 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/RangeSearchCursor.java
@@ -37,7 +37,7 @@
 			
 	public RangeSearchCursor(IBTreeLeafFrame frame) {
 		this.frame = frame;
-		this.frameTuple = frame.getTupleWriter().createTupleReference();
+		this.frameTuple = frame.createTupleReference();
 	}
 	
 	@Override
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleReference.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleReference.java
index 5a7ce72..284efc6 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleReference.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/SimpleTupleReference.java
@@ -8,6 +8,7 @@
 public class SimpleTupleReference implements IBTreeTupleReference {
 	
 	protected ByteBuffer buf;
+	protected int fieldStartIndex;
 	protected int fieldCount;	
 	protected int tupleStartOff;
 	protected int nullFlagsBytes;
@@ -29,6 +30,13 @@
 		this.fieldCount = fieldCount;
 		nullFlagsBytes = getNullFlagsBytes();
 		fieldSlotsBytes = getFieldSlotsBytes();
+		fieldStartIndex = 0;
+	}
+	
+	@Override
+	public void setFieldCount(int fieldStartIndex, int fieldCount) {
+		this.fieldCount = fieldCount;
+		this.fieldStartIndex = fieldStartIndex;
 	}
 	
 	@Override
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleReference.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleReference.java
index 5f8b6d8..1012800 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleReference.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleReference.java
@@ -8,6 +8,7 @@
 
 public class TypeAwareTupleReference implements IBTreeTupleReference {
 	protected ByteBuffer buf;
+	protected int fieldStartIndex;
 	protected int fieldCount;	
 	protected int tupleStartOff;
 	protected int nullFlagsBytes;
@@ -19,6 +20,7 @@
 	
 	public TypeAwareTupleReference(ITypeTrait[] typeTraits) {
 		this.typeTraits = typeTraits;
+		this.fieldStartIndex = 0;
 	}
 	
 	@Override
@@ -29,8 +31,9 @@
 		// decode field slots
 		int field = 0;
 		int cumul = 0;
+		int end = fieldStartIndex + fieldCount;
 		encDec.reset(buf.array(), tupleStartOff + nullFlagsBytes);
-		for(int i = 0; i < fieldCount; i++) {
+		for(int i = fieldStartIndex; i < end; i++) {
 			int staticDataLen = typeTraits[i].getStaticallyKnownDataLength();
 			if(staticDataLen == ITypeTrait.VARIABLE_LENGTH) {
 				cumul += encDec.decode();
@@ -49,6 +52,7 @@
 		resetByOffset(frame.getBuffer(), frame.getTupleOffset(tupleIndex));		
 	}
 	
+	@Override
 	public void setFieldCount(int fieldCount) {
 		this.fieldCount = fieldCount;
 		if(decodedFieldSlots == null) {
@@ -60,6 +64,13 @@
 			}
 		}		
 		nullFlagsBytes = getNullFlagsBytes();
+		this.fieldStartIndex = 0;
+	}
+	
+	@Override
+	public void setFieldCount(int fieldStartIndex, int fieldCount) {
+		setFieldCount(fieldCount);
+		this.fieldStartIndex = fieldStartIndex;		
 	}
 	
 	@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-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriter.java
index e82e07f..e47bf2f 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriter.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/tuples/TypeAwareTupleWriter.java
@@ -123,4 +123,8 @@
 	public ITypeTrait[] getTypeTraits() {
 		return typeTraits;
 	}
+	
+	public void setTypeTraits(ITypeTrait[] typeTraits) {
+		this.typeTraits = typeTraits;
+	}
 }
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
index 44bf9f5..88feb23 100644
--- 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
@@ -9,7 +9,7 @@
 
 	private List<ByteBuffer> resultBuffers;
 	private int numResultBuffers;
-	private int currentPos = -1;
+	private int currentPos = 0;
 	
 	public void setResults(List<ByteBuffer> resultBuffers, int numResultBuffers) {
 		this.resultBuffers = resultBuffers;
@@ -19,8 +19,8 @@
 		
 	@Override
 	public boolean hasNext() {
-		if(currentPos < numResultBuffers) return true;
-		else return false;		
+		if(currentPos+1 < numResultBuffers) return true;
+		else return false;
 	}
 
 	@Override
@@ -36,5 +36,5 @@
 	@Override
 	public void reset() {
 		currentPos = -1;		
-	}
+	}	
 }
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
index e3067a3..bb13d94 100644
--- 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
@@ -141,7 +141,7 @@
 			btree.search(btreeCursor, pred, opCtx);
 			while(btreeCursor.hasNext()) {
 				btreeCursor.next();
-				maxResultBufIdx = appendTupleToNewResults(btreeCursor, maxResultBufIdx);
+				maxResultBufIdx = appendTupleToNewResults(btreeCursor, maxResultBufIdx);				
 			}
 			btreeCursor.reset();
 		} catch (Exception e) {
@@ -194,7 +194,7 @@
 	}
 	
 	private int intersectList(IBTreeCursor btreeCursor, List<ByteBuffer> prevResultBuffers, int maxPrevBufIdx, List<ByteBuffer> newResultBuffers) throws IOException, Exception {
-		
+				
 		int newBufIdx = 0;
 		ByteBuffer newCurrentBuffer = newResultBuffers.get(0);
 		
diff --git a/hyracks-storage-am-invertedindex/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/SimpleConjunctiveSearcherTest.java b/hyracks-storage-am-invertedindex/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/SimpleConjunctiveSearcherTest.java
index fa5ec4c..788e01b 100644
--- a/hyracks-storage-am-invertedindex/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/SimpleConjunctiveSearcherTest.java
+++ b/hyracks-storage-am-invertedindex/src/test/java/edu/uci/ics/hyracks/storage/am/invertedindex/searchers/SimpleConjunctiveSearcherTest.java
@@ -35,9 +35,9 @@
 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.impls.BTree;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOp;
 import edu.uci.ics.hyracks.storage.am.btree.impls.BTreeOpContext;
@@ -110,8 +110,8 @@
     	    	
     	TypeAwareTupleWriterFactory tupleWriterFactory = new TypeAwareTupleWriterFactory(typeTraits);
     	//SimpleTupleWriterFactory tupleWriterFactory = new SimpleTupleWriterFactory();
-        IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(tupleWriterFactory);
-    	//IBTreeLeafFrameFactory leafFrameFactory = new FieldPrefixNSMLeafFrameFactory(tupleWriterFactory);
+        //IBTreeLeafFrameFactory leafFrameFactory = new NSMLeafFrameFactory(tupleWriterFactory);
+    	IBTreeLeafFrameFactory leafFrameFactory = new FieldPrefixNSMLeafFrameFactory(tupleWriterFactory);
         IBTreeInteriorFrameFactory interiorFrameFactory = new NSMInteriorFrameFactory(tupleWriterFactory);
         IBTreeMetaDataFrameFactory metaFrameFactory = new MetaDataFrameFactory();