diff --git a/algebricks/algebricks-runtime/src/main/java/edu/uci/ics/hyracks/algebricks/runtime/operators/meta/SubplanRuntimeFactory.java b/algebricks/algebricks-runtime/src/main/java/edu/uci/ics/hyracks/algebricks/runtime/operators/meta/SubplanRuntimeFactory.java
index 0499684..e5bede2 100644
--- a/algebricks/algebricks-runtime/src/main/java/edu/uci/ics/hyracks/algebricks/runtime/operators/meta/SubplanRuntimeFactory.java
+++ b/algebricks/algebricks-runtime/src/main/java/edu/uci/ics/hyracks/algebricks/runtime/operators/meta/SubplanRuntimeFactory.java
@@ -107,7 +107,8 @@
                             FrameUtils.flushFrame(frame, writer);
                             appender.reset(frame, true);
                             if (!appender.appendConcat(tRef.getFrameTupleAccessor(), tRef.getTupleIndex(), ta, t)) {
-                                throw new IllegalStateException("Could not write frame.");
+                                throw new HyracksDataException(
+                                        "Could not write frame: subplan result is larger than the single-frame limit.");
                             }
                         }
                     }
diff --git a/algebricks/algebricks-runtime/src/main/java/edu/uci/ics/hyracks/algebricks/runtime/operators/std/UnnestRuntimeFactory.java b/algebricks/algebricks-runtime/src/main/java/edu/uci/ics/hyracks/algebricks/runtime/operators/std/UnnestRuntimeFactory.java
index 81f0afa..88dc19f 100644
--- a/algebricks/algebricks-runtime/src/main/java/edu/uci/ics/hyracks/algebricks/runtime/operators/std/UnnestRuntimeFactory.java
+++ b/algebricks/algebricks-runtime/src/main/java/edu/uci/ics/hyracks/algebricks/runtime/operators/std/UnnestRuntimeFactory.java
@@ -144,7 +144,8 @@
                                     }
                                 }
                                 if (hasPositionalVariable) {
-                                    tupleBuilder.getDataOutput().writeByte(0);
+                                    // Write the positional variable as an INT32
+                                    tupleBuilder.getDataOutput().writeByte(3);
                                     tupleBuilder.getDataOutput().writeInt(offset + tupleCount++);
                                     tupleBuilder.addFieldEndOffset();
                                 }
diff --git a/hyracks/hyracks-api/src/main/java/edu/uci/ics/hyracks/api/context/IHyracksCommonContext.java b/hyracks/hyracks-api/src/main/java/edu/uci/ics/hyracks/api/context/IHyracksCommonContext.java
index c75f9f9..1af32de 100644
--- a/hyracks/hyracks-api/src/main/java/edu/uci/ics/hyracks/api/context/IHyracksCommonContext.java
+++ b/hyracks/hyracks-api/src/main/java/edu/uci/ics/hyracks/api/context/IHyracksCommonContext.java
@@ -25,4 +25,6 @@
     public IIOManager getIOManager();
 
     public ByteBuffer allocateFrame() throws HyracksDataException;
+    
+    public void deallocateFrames(int frameCount);
 }
\ No newline at end of file
diff --git a/hyracks/hyracks-client/src/main/java/edu/uci/ics/hyracks/client/dataset/DatasetClientContext.java b/hyracks/hyracks-client/src/main/java/edu/uci/ics/hyracks/client/dataset/DatasetClientContext.java
index aa7008f..3ea81ef 100644
--- a/hyracks/hyracks-client/src/main/java/edu/uci/ics/hyracks/client/dataset/DatasetClientContext.java
+++ b/hyracks/hyracks-client/src/main/java/edu/uci/ics/hyracks/client/dataset/DatasetClientContext.java
@@ -41,4 +41,10 @@
         return ByteBuffer.allocate(frameSize);
     }
 
+    @Override
+    public void deallocateFrames(int frameCount) {
+        // TODO Auto-generated method stub
+        
+    }
+
 }
diff --git a/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/Task.java b/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/Task.java
index 53e5a01..bbbe0f5 100644
--- a/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/Task.java
+++ b/hyracks/hyracks-control/hyracks-control-nc/src/main/java/edu/uci/ics/hyracks/control/nc/Task.java
@@ -114,6 +114,11 @@
     }
 
     @Override
+    public void deallocateFrames(int frameCount) {
+        joblet.deallocateFrames(frameCount);
+    }
+
+    @Override
     public int getFrameSize() {
         return joblet.getFrameSize();
     }
diff --git a/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/preclustered/PreclusteredGroupWriter.java b/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/preclustered/PreclusteredGroupWriter.java
index 7773765..66efc03 100644
--- a/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/preclustered/PreclusteredGroupWriter.java
+++ b/hyracks/hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/group/preclustered/PreclusteredGroupWriter.java
@@ -44,6 +44,8 @@
 
     private boolean first;
 
+    private boolean isFailed = false;
+
     public PreclusteredGroupWriter(IHyracksTaskContext ctx, int[] groupFields, IBinaryComparator[] comparators,
             IAggregatorDescriptor aggregator, RecordDescriptor inRecordDesc, RecordDescriptor outRecordDesc,
             IFrameWriter writer) throws HyracksDataException {
@@ -149,12 +151,13 @@
 
     @Override
     public void fail() throws HyracksDataException {
+        isFailed = true;
         writer.fail();
     }
 
     @Override
     public void close() throws HyracksDataException {
-        if (!first) {
+        if (!isFailed && !first) {
             writeOutput(copyFrameAccessor, copyFrameAccessor.getTupleCount() - 1);
             if (appender.getTupleCount() > 0) {
                 FrameUtils.flushFrame(outFrame, writer);
diff --git a/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/ondisk/OnDiskInvertedIndex.java b/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/ondisk/OnDiskInvertedIndex.java
index 0ab2f4d..b03489c 100644
--- a/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/ondisk/OnDiskInvertedIndex.java
+++ b/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/ondisk/OnDiskInvertedIndex.java
@@ -561,6 +561,12 @@
         public ByteBuffer allocateFrame() {
             return ByteBuffer.allocate(FRAME_SIZE);
         }
+        
+        @Override
+        public void deallocateFrames(int frameCount) {
+            // TODO Auto-generated method stub
+            
+        }
     }
 
     @Override
diff --git a/hyracks/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestTaskContext.java b/hyracks/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestTaskContext.java
index 10b5582..f18099b 100644
--- a/hyracks/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestTaskContext.java
+++ b/hyracks/hyracks-test-support/src/main/java/edu/uci/ics/hyracks/test/support/TestTaskContext.java
@@ -46,6 +46,10 @@
     public ByteBuffer allocateFrame() {
         return jobletContext.allocateFrame();
     }
+    
+    @Override
+    public void deallocateFrames(int frameCount) {
+    }
 
     @Override
     public int getFrameSize() {