diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.1.ddl.sqlpp b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.1.ddl.sqlpp
new file mode 100644
index 0000000..3100af6
--- /dev/null
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.1.ddl.sqlpp
@@ -0,0 +1,44 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+drop dataverse test if exists;
+create dataverse test;
+use test;
+
+create type TweetType as open {
+  id : int64
+};
+
+create dataset Tweets(TweetType) primary key id;
+
+drop type NearbyBuildingType if exists;
+create type NearbyBuildingType as open {
+    buildingId: int64,
+    buildingType : string,
+    buildingLocation : point
+};
+create dataset NearbyBuildings(NearbyBuildingType) primary key buildingId;
+
+create function annotateTweet(x) {
+    LET nearby_buildings = (select r.buildingType as buildingType, count(r) as cnt
+       from NearbyBuildings r
+       where spatial_intersect(create_point(x.latitude, x.longitude), create_circle(r.buildingLocation, 3.0))
+       group by r.buildingType)
+    select x.*, nearby_buildings
+};
+
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.2.update.sqlpp b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.2.update.sqlpp
new file mode 100644
index 0000000..ab13484
--- /dev/null
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.2.update.sqlpp
@@ -0,0 +1,25 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+use test;
+insert into Tweets([{"id": 1, "text" : "im tweet", "latitude":0.0, "longitude" : 0.0}]);
+
+insert into NearbyBuildings([{"buildingId" : 0, "buildingType" : "school", "buildingLocation" : point("1, 1")},
+{"buildingId" : 1, "buildingType" : "school", "buildingLocation" : point("-1, 1")},
+{"buildingId" : 2, "buildingType" : "hospital", "buildingLocation" : point("1, -1")}]);
\ No newline at end of file
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.3.query.sqlpp b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.3.query.sqlpp
new file mode 100644
index 0000000..55a1c37
--- /dev/null
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.3.query.sqlpp
@@ -0,0 +1,20 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+ use test;
+select value annotateTweet(t) from Tweets t;
\ No newline at end of file
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.4.ddl.sqlpp b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.4.ddl.sqlpp
new file mode 100644
index 0000000..d4b1d9d
--- /dev/null
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/queries_sqlpp/group-by/redundant-var-in-groupby/redundant-var-in-groupby.4.ddl.sqlpp
@@ -0,0 +1,19 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+drop dataverse test;
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/results/group-by/redundant-var-in-groupby/redundant-var-in-groupby.1.adm b/asterixdb/asterix-app/src/test/resources/runtimets/results/group-by/redundant-var-in-groupby/redundant-var-in-groupby.1.adm
new file mode 100644
index 0000000..c563f9c
--- /dev/null
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/results/group-by/redundant-var-in-groupby/redundant-var-in-groupby.1.adm
@@ -0,0 +1 @@
+[ { "nearby_buildings": [ { "buildingType": "hospital", "cnt": 1 }, { "buildingType": "school", "cnt": 2 } ], "id": 1, "text": "im tweet", "latitude": 0.0, "longitude": 0.0 } ]
diff --git a/asterixdb/asterix-app/src/test/resources/runtimets/testsuite_sqlpp.xml b/asterixdb/asterix-app/src/test/resources/runtimets/testsuite_sqlpp.xml
index b5fc053..6edc7bf 100644
--- a/asterixdb/asterix-app/src/test/resources/runtimets/testsuite_sqlpp.xml
+++ b/asterixdb/asterix-app/src/test/resources/runtimets/testsuite_sqlpp.xml
@@ -3220,6 +3220,11 @@
         <expected-error>The byte size of a single group</expected-error>
       </compilation-unit>
     </test-case>
+    <test-case FilePath="group-by">
+      <compilation-unit name="redundant-var-in-groupby">
+        <output-dir compare="Text">redundant-var-in-groupby</output-dir>
+      </compilation-unit>
+    </test-case>
   </test-group>
   <test-group name="index-join">
     <test-case FilePath="index-join">
diff --git a/hyracks-fullstack/algebricks/algebricks-rewriter/src/main/java/org/apache/hyracks/algebricks/rewriter/rules/AbstractIntroduceGroupByCombinerRule.java b/hyracks-fullstack/algebricks/algebricks-rewriter/src/main/java/org/apache/hyracks/algebricks/rewriter/rules/AbstractIntroduceGroupByCombinerRule.java
index dc48d96..7b9c255 100644
--- a/hyracks-fullstack/algebricks/algebricks-rewriter/src/main/java/org/apache/hyracks/algebricks/rewriter/rules/AbstractIntroduceGroupByCombinerRule.java
+++ b/hyracks-fullstack/algebricks/algebricks-rewriter/src/main/java/org/apache/hyracks/algebricks/rewriter/rules/AbstractIntroduceGroupByCombinerRule.java
@@ -84,10 +84,12 @@
             // p.second.getValue() should always return a VariableReferenceExpression, hence
             // usedDecorVars should always contain only one variable.
             p.second.getValue().getUsedVariables(usedDecorVars);
-            if (!newGbyLiveVars.contains(usedDecorVars.get(0))) {
+            LogicalVariable usedVar = usedDecorVars.get(0);
+            if (!newGbyLiveVars.contains(usedVar)) {
                 // Let the left-hand side of gbyOp's decoration expressions populated through the combiner group-by without
                 // any intermediate assignment.
                 newGbyOp.addDecorExpression(null, p.second.getValue());
+                newGbyLiveVars.add(usedVar);
             }
         }
         newGbyOp.setExecutionMode(ExecutionMode.LOCAL);
@@ -97,14 +99,11 @@
         Object v2 = gbyOp.getAnnotations().get(OperatorAnnotations.USE_EXTERNAL_GROUP_BY);
         newGbyOp.getAnnotations().put(OperatorAnnotations.USE_EXTERNAL_GROUP_BY, v2);
 
-        List<LogicalVariable> propagatedVars = new LinkedList<LogicalVariable>();
-        VariableUtilities.getProducedVariables(newGbyOp, propagatedVars);
-
         Set<LogicalVariable> freeVars = new HashSet<LogicalVariable>();
         OperatorPropertiesUtil.getFreeVariablesInSubplans(gbyOp, freeVars);
 
         for (LogicalVariable var : freeVars) {
-            if (!propagatedVars.contains(var)) {
+            if (!newGbyLiveVars.contains(var)) {
                 LogicalVariable newDecorVar = context.newVar();
                 VariableReferenceExpression varRef = new VariableReferenceExpression(var);
                 varRef.setSourceLocation(gbyOp.getSourceLocation());
@@ -435,8 +434,8 @@
      *            The optimization context.
      * @param nestedGby
      *            The nested gby operator in the global gby operator's subplan.
-     * @param firstAggVar
-     *            The first aggregation variable produced by the combiner gby.
+     * @param aggregateVarsProducedByCombiner
+     *            The aggregation variables produced by the combiner gby.
      */
     protected abstract void processNullTest(IOptimizationContext context, GroupByOperator nestedGby,
             List<LogicalVariable> aggregateVarsProducedByCombiner);