diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/ExternalDataLookupOperator.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/ExternalDataLookupOperator.java
deleted file mode 100644
index 60aec27..0000000
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/ExternalDataLookupOperator.java
+++ /dev/null
@@ -1,122 +0,0 @@
-/*
- * 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.
- */
-package org.apache.hyracks.algebricks.core.algebra.operators.logical;
-
-import java.util.ArrayList;
-import java.util.List;
-
-import org.apache.commons.lang3.mutable.Mutable;
-import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
-import org.apache.hyracks.algebricks.core.algebra.base.ILogicalExpression;
-import org.apache.hyracks.algebricks.core.algebra.base.LogicalOperatorTag;
-import org.apache.hyracks.algebricks.core.algebra.base.LogicalVariable;
-import org.apache.hyracks.algebricks.core.algebra.expressions.IVariableTypeEnvironment;
-import org.apache.hyracks.algebricks.core.algebra.metadata.IDataSource;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.visitors.VariableUtilities;
-import org.apache.hyracks.algebricks.core.algebra.properties.VariablePropagationPolicy;
-import org.apache.hyracks.algebricks.core.algebra.typing.ITypingContext;
-import org.apache.hyracks.algebricks.core.algebra.typing.NonPropagatingTypeEnvironment;
-import org.apache.hyracks.algebricks.core.algebra.visitors.ILogicalExpressionReferenceTransform;
-import org.apache.hyracks.algebricks.core.algebra.visitors.ILogicalOperatorVisitor;
-
-public class ExternalDataLookupOperator extends AbstractDataSourceOperator {
-
-    private final List<Object> variableTypes;
-    protected final Mutable<ILogicalExpression> expression;
-    private boolean propagateInput;
-
-    public ExternalDataLookupOperator(List<LogicalVariable> variables, Mutable<ILogicalExpression> expression,
-            List<Object> variableTypes, boolean propagateInput, IDataSource<?> dataSource) {
-        super(variables, dataSource);
-        this.expression = expression;
-        this.variableTypes = variableTypes;
-        this.propagateInput = propagateInput;
-    }
-
-    @Override
-    public LogicalOperatorTag getOperatorTag() {
-        return LogicalOperatorTag.EXTERNAL_LOOKUP;
-    }
-
-    @Override
-    public IVariableTypeEnvironment computeOutputTypeEnvironment(ITypingContext ctx) throws AlgebricksException {
-        IVariableTypeEnvironment env = null;
-        if (propagateInput) {
-            env = createPropagatingAllInputsTypeEnvironment(ctx);
-        } else {
-            env = new NonPropagatingTypeEnvironment(ctx.getExpressionTypeComputer(), ctx.getMetadataProvider());
-        }
-        env.setVarType(variables.get(0), variableTypes.get(0));
-        return env;
-    }
-
-    public List<Object> getVariableTypes() {
-        return variableTypes;
-    }
-
-    @Override
-    public <R, T> R accept(ILogicalOperatorVisitor<R, T> visitor, T arg) throws AlgebricksException {
-        return visitor.visitExternalDataLookupOperator(this, arg);
-    }
-
-    @Override
-    public boolean isMap() {
-        return false;
-    }
-
-    public boolean isPropagateInput() {
-        return propagateInput;
-    }
-
-    public void setPropagateInput(boolean propagateInput) {
-        this.propagateInput = propagateInput;
-    }
-
-    @Override
-    public VariablePropagationPolicy getVariablePropagationPolicy() {
-        return new VariablePropagationPolicy() {
-            @Override
-            public void propagateVariables(IOperatorSchema target, IOperatorSchema... sources)
-                    throws AlgebricksException {
-                if (propagateInput) {
-                    ArrayList<LogicalVariable> usedVariables = new ArrayList<LogicalVariable>();
-                    VariableUtilities.getUsedVariables(ExternalDataLookupOperator.this, usedVariables);
-                    int numOfSources = sources.length;
-                    for (int i = 0; i < numOfSources; i++) {
-                        for (LogicalVariable v : sources[i]) {
-                            if (!usedVariables.contains(v)) {
-                                target.addVariable(v);
-                            }
-                        }
-                    }
-                }
-                target.addVariable(variables.get(0));
-            }
-        };
-    }
-
-    public Mutable<ILogicalExpression> getExpressionRef() {
-        return expression;
-    }
-
-    @Override
-    public boolean acceptExpressionTransform(ILogicalExpressionReferenceTransform visitor) throws AlgebricksException {
-        return visitor.transform(expression);
-    }
-}
\ No newline at end of file
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/UnnestMapOperator.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/UnnestMapOperator.java
index 815c36c..09d02f2 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/UnnestMapOperator.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/UnnestMapOperator.java
@@ -31,14 +31,9 @@
 import org.apache.hyracks.algebricks.core.algebra.typing.NonPropagatingTypeEnvironment;
 import org.apache.hyracks.algebricks.core.algebra.visitors.ILogicalOperatorVisitor;
 
-/**
- * This operator may go away after we add indexes to Algebricks.
- */
 public class UnnestMapOperator extends AbstractUnnestOperator {
-
-    private final List<Object> variableTypes; // TODO: get rid of this and  deprecate UnnestMap
+    private final List<Object> variableTypes;
     private boolean propagateInput;
-
     private List<Mutable<ILogicalExpression>> additionalFilteringExpressions;
     private List<LogicalVariable> minFilterVars;
     private List<LogicalVariable> maxFilterVars;
@@ -132,10 +127,8 @@
         return additionalFilteringExpressions;
     }
 
-    /*
     @Override
     public boolean isMap() {
-        return !propagateInput;
+        return true;
     }
-    */
 }
\ No newline at end of file
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/FDsAndEquivClassesVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/FDsAndEquivClassesVisitor.java
index 398b4d2..1805289 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/FDsAndEquivClassesVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/FDsAndEquivClassesVisitor.java
@@ -54,7 +54,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -738,13 +737,6 @@
         return null;
     }
 
-    @Override
-    public Void visitExternalDataLookupOperator(ExternalDataLookupOperator op, IOptimizationContext ctx)
-            throws AlgebricksException {
-        propagateFDsAndEquivClasses(op, ctx);
-        return null;
-    }
-
     /**
      * Propagate equivalences that carried in expressions to the variables that
      * they are assigned to.
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/IsomorphismOperatorVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/IsomorphismOperatorVisitor.java
index eb6cd15..f849a11 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/IsomorphismOperatorVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/IsomorphismOperatorVisitor.java
@@ -25,7 +25,6 @@
 import java.util.Map.Entry;
 
 import org.apache.commons.lang3.mutable.Mutable;
-
 import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
 import org.apache.hyracks.algebricks.common.utils.Pair;
 import org.apache.hyracks.algebricks.common.utils.Triple;
@@ -43,7 +42,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -536,12 +534,6 @@
         return Boolean.TRUE;
     }
 
-    @Override
-    public Boolean visitExternalDataLookupOperator(ExternalDataLookupOperator op, ILogicalOperator arg)
-            throws AlgebricksException {
-        return Boolean.FALSE;
-    }
-
     private Boolean compareIOrderAndExpressions(List<Pair<IOrder, Mutable<ILogicalExpression>>> opOrderExprs,
             List<Pair<IOrder, Mutable<ILogicalExpression>>> argOrderExprs) {
         if (opOrderExprs.size() != argOrderExprs.size())
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/IsomorphismVariableMappingVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/IsomorphismVariableMappingVisitor.java
index 7b0b944..b81f747 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/IsomorphismVariableMappingVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/IsomorphismVariableMappingVisitor.java
@@ -25,7 +25,6 @@
 
 import org.apache.commons.lang3.mutable.Mutable;
 import org.apache.commons.lang3.mutable.MutableObject;
-
 import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
 import org.apache.hyracks.algebricks.common.utils.Pair;
 import org.apache.hyracks.algebricks.common.utils.Triple;
@@ -44,7 +43,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -272,8 +270,7 @@
     }
 
     @Override
-    public Void visitTokenizeOperator(TokenizeOperator op, ILogicalOperator arg)
-            throws AlgebricksException {
+    public Void visitTokenizeOperator(TokenizeOperator op, ILogicalOperator arg) throws AlgebricksException {
         mapVariablesStandard(op, arg);
         return null;
     }
@@ -468,12 +465,6 @@
     }
 
     @Override
-    public Void visitExternalDataLookupOperator(ExternalDataLookupOperator op, ILogicalOperator arg)
-            throws AlgebricksException {
-        return null;
-    }
-
-    @Override
     public Void visitOuterUnnestOperator(OuterUnnestOperator op, ILogicalOperator arg) throws AlgebricksException {
         mapVariablesStandard(op, arg);
         return null;
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/LogicalOperatorDeepCopyWithNewVariablesVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/LogicalOperatorDeepCopyWithNewVariablesVisitor.java
index 9d83ae5..5e7ba79 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/LogicalOperatorDeepCopyWithNewVariablesVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/LogicalOperatorDeepCopyWithNewVariablesVisitor.java
@@ -41,7 +41,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IntersectOperator;
@@ -530,17 +529,6 @@
     }
 
     @Override
-    public ILogicalOperator visitExternalDataLookupOperator(ExternalDataLookupOperator op, ILogicalOperator arg)
-            throws AlgebricksException {
-        ExternalDataLookupOperator opCopy = new ExternalDataLookupOperator(deepCopyVariableList(op.getVariables()),
-                exprDeepCopyVisitor.deepCopyExpressionReference(op.getExpressionRef()), op.getVariableTypes(),
-                op.isPropagateInput(), op.getDataSource());
-        deepCopyInputsAnnotationsAndExecutionMode(op, arg, opCopy);
-        return opCopy;
-
-    }
-
-    @Override
     public ILogicalOperator visitOuterUnnestOperator(OuterUnnestOperator op, ILogicalOperator arg)
             throws AlgebricksException {
         OuterUnnestOperator opCopy = new OuterUnnestOperator(deepCopyVariable(op.getVariable()),
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/LogicalPropertiesVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/LogicalPropertiesVisitor.java
index 9de0992..2f3725d 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/LogicalPropertiesVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/LogicalPropertiesVisitor.java
@@ -35,7 +35,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -352,12 +351,6 @@
     }
 
     @Override
-    public Void visitExternalDataLookupOperator(ExternalDataLookupOperator op, IOptimizationContext arg)
-            throws AlgebricksException {
-        return null;
-    }
-
-    @Override
     public Void visitOuterUnnestOperator(OuterUnnestOperator op, IOptimizationContext arg) throws AlgebricksException {
         return null;
     }
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/OperatorDeepCopyVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/OperatorDeepCopyVisitor.java
index 8d436d1..7fd3c46 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/OperatorDeepCopyVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/OperatorDeepCopyVisitor.java
@@ -40,7 +40,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -370,15 +369,6 @@
     }
 
     @Override
-    public ILogicalOperator visitExternalDataLookupOperator(ExternalDataLookupOperator op, Void arg)
-            throws AlgebricksException {
-        ArrayList<LogicalVariable> newInputList = new ArrayList<LogicalVariable>();
-        newInputList.addAll(op.getVariables());
-        return new ExternalDataLookupOperator(newInputList, deepCopyExpressionRef(op.getExpressionRef()),
-                new ArrayList<Object>(op.getVariableTypes()), op.isPropagateInput(), op.getDataSource());
-    }
-
-    @Override
     public ILogicalOperator visitMaterializeOperator(MaterializeOperator op, Void arg) throws AlgebricksException {
         return new MaterializeOperator();
     }
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/ProducedVariableVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/ProducedVariableVisitor.java
index d23ff94..0c1e3de 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/ProducedVariableVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/ProducedVariableVisitor.java
@@ -39,7 +39,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -276,12 +275,6 @@
     }
 
     @Override
-    public Void visitExternalDataLookupOperator(ExternalDataLookupOperator op, Void arg) throws AlgebricksException {
-        producedVariables.add(op.getVariables().get(0));
-        return null;
-    }
-
-    @Override
     public Void visitOuterUnnestOperator(OuterUnnestOperator op, Void arg) throws AlgebricksException {
         return visitUnnestNonMapOperator(op);
     }
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/SchemaVariableVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/SchemaVariableVisitor.java
index 5c6d3c3..c2a20df 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/SchemaVariableVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/SchemaVariableVisitor.java
@@ -23,7 +23,6 @@
 import java.util.List;
 
 import org.apache.commons.lang3.mutable.Mutable;
-
 import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
 import org.apache.hyracks.algebricks.common.utils.Pair;
 import org.apache.hyracks.algebricks.core.algebra.base.ILogicalExpression;
@@ -40,7 +39,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -320,26 +318,6 @@
     }
 
     @Override
-    public Void visitExternalDataLookupOperator(ExternalDataLookupOperator op, Void arg) throws AlgebricksException {
-        ArrayList<LogicalVariable> liveVariables = new ArrayList<LogicalVariable>();
-        ArrayList<LogicalVariable> usedVariables = new ArrayList<LogicalVariable>();
-        //get used variables
-        op.getExpressionRef().getValue().getUsedVariables(usedVariables);
-        //live variables - used variables
-        for (Mutable<ILogicalOperator> c : op.getInputs()) {
-            VariableUtilities.getLiveVariables(c.getValue(), liveVariables);
-        }
-        for (LogicalVariable v : liveVariables) {
-            if (!usedVariables.contains(v)) {
-                schemaVariables.add(v);
-            }
-        }
-        VariableUtilities.getProducedVariables(op, schemaVariables);
-        //+ produced variables
-        return null;
-    }
-
-    @Override
     public Void visitOuterUnnestOperator(OuterUnnestOperator op, Void arg) throws AlgebricksException {
         standardLayout(op);
         return null;
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/SubstituteVariableVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/SubstituteVariableVisitor.java
index d8e25f7..3548497 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/SubstituteVariableVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/SubstituteVariableVisitor.java
@@ -38,7 +38,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -467,21 +466,6 @@
     }
 
     @Override
-    public Void visitExternalDataLookupOperator(ExternalDataLookupOperator op,
-            Pair<LogicalVariable, LogicalVariable> pair) throws AlgebricksException {
-        List<LogicalVariable> variables = op.getVariables();
-        for (int i = 0; i < variables.size(); i++) {
-            if (variables.get(i) == pair.first) {
-                variables.set(i, pair.second);
-                return null;
-            }
-        }
-        op.getExpressionRef().getValue().substituteVar(pair.first, pair.second);
-        substVarTypes(op, pair);
-        return null;
-    }
-
-    @Override
     public Void visitOuterUnnestOperator(OuterUnnestOperator op, Pair<LogicalVariable, LogicalVariable> pair)
             throws AlgebricksException {
         return visitUnnestNonMapOperator(op, pair);
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/UsedVariableVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/UsedVariableVisitor.java
index ef02feb..5cfd619 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/UsedVariableVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/operators/logical/visitors/UsedVariableVisitor.java
@@ -38,7 +38,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -431,12 +430,6 @@
     }
 
     @Override
-    public Void visitExternalDataLookupOperator(ExternalDataLookupOperator op, Void arg) throws AlgebricksException {
-        op.getExpressionRef().getValue().getUsedVariables(usedVariables);
-        return null;
-    }
-
-    @Override
     public Void visitOuterUnnestOperator(OuterUnnestOperator op, Void arg) throws AlgebricksException {
         op.getExpressionRef().getValue().getUsedVariables(usedVariables);
         return null;
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/prettyprint/LogicalOperatorPrettyPrintVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/prettyprint/LogicalOperatorPrettyPrintVisitor.java
index 0514fbd..ca35284 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/prettyprint/LogicalOperatorPrettyPrintVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/prettyprint/LogicalOperatorPrettyPrintVisitor.java
@@ -36,7 +36,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -494,14 +493,4 @@
         }
         sb.append("]");
     }
-
-    @Override
-    public String visitExternalDataLookupOperator(ExternalDataLookupOperator op, Integer indent)
-            throws AlgebricksException {
-        StringBuilder buffer = new StringBuilder();
-        addIndent(buffer, indent)
-                .append("external-instant-lookup " + op.getVariables() + " <- " + op.getExpressionRef().getValue());
-        return buffer.toString();
-    }
-
 }
diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/visitors/ILogicalOperatorVisitor.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/visitors/ILogicalOperatorVisitor.java
index 6509e2a..ebb0198 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/visitors/ILogicalOperatorVisitor.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/visitors/ILogicalOperatorVisitor.java
@@ -27,7 +27,6 @@
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.EmptyTupleSourceOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExtensionOperator;
-import org.apache.hyracks.algebricks.core.algebra.operators.logical.ExternalDataLookupOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.GroupByOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.IndexInsertDeleteUpsertOperator;
 import org.apache.hyracks.algebricks.core.algebra.operators.logical.InnerJoinOperator;
@@ -120,8 +119,6 @@
 
     public R visitIndexInsertDeleteUpsertOperator(IndexInsertDeleteUpsertOperator op, T tag) throws AlgebricksException;
 
-    public R visitExternalDataLookupOperator(ExternalDataLookupOperator op, T arg) throws AlgebricksException;
-
     public R visitTokenizeOperator(TokenizeOperator op, T arg) throws AlgebricksException;
 
 }