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 2f4131d..7f32f6d 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
@@ -75,15 +75,21 @@
             IBinaryComparatorFactory[] cmpFactories, IModificationOperationCallback modificationCallback,
             ISearchOperationCallback searchCallback) {
         this.accessor = accessor;
-        this.cmp = MultiComparator.create(cmpFactories);
+        
+        if (cmpFactories[0] != null) {
+            this.cmp = MultiComparator.create(cmpFactories);
+        } else {
+            this.cmp = null;
+        }
+        
         this.leafFrameFactory = leafFrameFactory;
         this.leafFrame = (IBTreeLeafFrame) leafFrameFactory.createFrame();
-        if (leafFrame != null) {
+        if (leafFrame != null && this.cmp != null) {
             leafFrame.setMultiComparator(cmp);
         }
         this.interiorFrameFactory = interiorFrameFactory;
         this.interiorFrame = (IBTreeInteriorFrame) interiorFrameFactory.createFrame();
-        if (interiorFrame != null) {
+        if (interiorFrame != null && this.cmp != null) {
             interiorFrame.setMultiComparator(cmp);
         }
         this.metaFrame = metaFrame;
diff --git a/hyracks-storage-am-lsm-btree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/btree/impls/LSMBTreeOpContext.java b/hyracks-storage-am-lsm-btree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/btree/impls/LSMBTreeOpContext.java
index 78e0848..04997b5 100644
--- a/hyracks-storage-am-lsm-btree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/btree/impls/LSMBTreeOpContext.java
+++ b/hyracks-storage-am-lsm-btree/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/btree/impls/LSMBTreeOpContext.java
@@ -15,6 +15,7 @@
 
 package edu.uci.ics.hyracks.storage.am.lsm.btree.impls;
 
+import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparatorFactory;
 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.BTreeOpContext;
@@ -43,16 +44,21 @@
     public LSMBTreeOpContext(BTree memBTree, ITreeIndexFrameFactory insertLeafFrameFactory,
             ITreeIndexFrameFactory deleteLeafFrameFactory, IModificationOperationCallback modificationCallback,
             ISearchOperationCallback searchCallback) {
-        this.cmp = MultiComparator.create(memBTree.getComparatorFactories());
+        IBinaryComparatorFactory cmpFactories[] = memBTree.getComparatorFactories();
+        if (cmpFactories[0] != null) {
+            this.cmp = MultiComparator.create(memBTree.getComparatorFactories());
+        } else {
+            this.cmp = null;
+        }
         this.memBTree = memBTree;
         this.insertLeafFrameFactory = insertLeafFrameFactory;
         this.deleteLeafFrameFactory = deleteLeafFrameFactory;
         this.insertLeafFrame = (IBTreeLeafFrame) insertLeafFrameFactory.createFrame();
         this.deleteLeafFrame = (IBTreeLeafFrame) deleteLeafFrameFactory.createFrame();
-        if (insertLeafFrame != null) {
+        if (insertLeafFrame != null && this.cmp != null) {
             insertLeafFrame.setMultiComparator(cmp);
         }
-        if (deleteLeafFrame != null) {
+        if (deleteLeafFrame != null && this.cmp != null) {
             deleteLeafFrame.setMultiComparator(cmp);
         }
         this.modificationCallback = modificationCallback;
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
index 6ff55bc..219ab30 100644
--- 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
@@ -53,7 +53,13 @@
     public RTreeOpContext(IRTreeLeafFrame leafFrame, IRTreeInteriorFrame interiorFrame,
             ITreeIndexMetaDataFrame metaFrame, IBinaryComparatorFactory[] cmpFactories, int treeHeightHint,
             IModificationOperationCallback modificationCallback) {
-        this.cmp = MultiComparator.create(cmpFactories);
+        
+        if (cmpFactories[0] != null) { 
+            this.cmp = MultiComparator.create(cmpFactories);
+        } else {
+            this.cmp = null;
+        }
+        
         this.interiorFrame = interiorFrame;
         this.leafFrame = leafFrame;
         this.metaFrame = metaFrame;