cross merge fullstack_release_candidate into trunk
git-svn-id: https://hyracks.googlecode.com/svn/trunk@3208 123451ca-8445-de46-9d55-352943316053
diff --git a/fullstack/hivesterix/hivesterix-optimizer/pom.xml b/fullstack/hivesterix/hivesterix-optimizer/pom.xml
new file mode 100644
index 0000000..4e6032e
--- /dev/null
+++ b/fullstack/hivesterix/hivesterix-optimizer/pom.xml
@@ -0,0 +1,47 @@
+<?xml version="1.0"?>
+<project
+ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
+ xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+ <modelVersion>4.0.0</modelVersion>
+ <parent>
+ <artifactId>hivesterix</artifactId>
+ <groupId>edu.uci.ics.hyracks</groupId>
+ <version>0.2.3-SNAPSHOT</version>
+ </parent>
+
+ <artifactId>hivesterix-optimizer</artifactId>
+ <name>hivesterix-optimizer</name>
+
+ <build>
+ <plugins>
+ <plugin>
+ <groupId>org.apache.maven.plugins</groupId>
+ <artifactId>maven-compiler-plugin</artifactId>
+ <version>2.0.2</version>
+ <configuration>
+ <source>1.7</source>
+ <target>1.7</target>
+ <encoding>UTF-8</encoding>
+ <fork>true</fork>
+ </configuration>
+ </plugin>
+ </plugins>
+ </build>
+
+ <dependencies>
+ <dependency>
+ <groupId>edu.uci.ics.hyracks</groupId>
+ <artifactId>hivesterix-common</artifactId>
+ <version>0.2.3-SNAPSHOT</version>
+ <type>jar</type>
+ <scope>compile</scope>
+ </dependency>
+ <dependency>
+ <groupId>edu.uci.ics.hyracks</groupId>
+ <artifactId>hivesterix-translator</artifactId>
+ <version>0.2.3-SNAPSHOT</version>
+ <type>jar</type>
+ <scope>compile</scope>
+ </dependency>
+ </dependencies>
+</project>
diff --git a/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rulecollections/HiveRuleCollections.java b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rulecollections/HiveRuleCollections.java
new file mode 100644
index 0000000..7e4e271
--- /dev/null
+++ b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rulecollections/HiveRuleCollections.java
@@ -0,0 +1,113 @@
+package edu.uci.ics.hivesterix.optimizer.rulecollections;
+
+import java.util.LinkedList;
+
+import edu.uci.ics.hivesterix.optimizer.rules.InsertProjectBeforeWriteRule;
+import edu.uci.ics.hivesterix.optimizer.rules.IntroduceEarlyProjectRule;
+import edu.uci.ics.hivesterix.optimizer.rules.LocalGroupByRule;
+import edu.uci.ics.hivesterix.optimizer.rules.RemoveRedundantSelectRule;
+import edu.uci.ics.hyracks.algebricks.core.rewriter.base.HeuristicOptimizer;
+import edu.uci.ics.hyracks.algebricks.core.rewriter.base.IAlgebraicRewriteRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.BreakSelectIntoConjunctsRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.ComplexJoinInferenceRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.ConsolidateAssignsRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.ConsolidateSelectsRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.EliminateSubplanRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.EnforceStructuralPropertiesRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.ExtractCommonOperatorsRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.ExtractGbyExpressionsRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.FactorRedundantGroupAndDecorVarsRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.InferTypesRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.InlineVariablesRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.InsertProjectBeforeUnionRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.IntroduceAggregateCombinerRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.IntroduceGroupByCombinerRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.IsolateHyracksOperatorsRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.PullSelectOutOfEqJoin;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushLimitDownRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushProjectDownRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushProjectIntoDataSourceScanRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushSelectDownRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.PushSelectIntoJoinRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.ReinferAllTypesRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.RemoveRedundantProjectionRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.RemoveUnusedAssignAndAggregateRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.SetAlgebricksPhysicalOperatorsRule;
+import edu.uci.ics.hyracks.algebricks.rewriter.rules.SetExecutionModeRule;
+
+public final class HiveRuleCollections {
+
+ public final static LinkedList<IAlgebraicRewriteRule> NORMALIZATION = new LinkedList<IAlgebraicRewriteRule>();
+ static {
+ NORMALIZATION.add(new EliminateSubplanRule());
+ NORMALIZATION.add(new IntroduceAggregateCombinerRule());
+ NORMALIZATION.add(new BreakSelectIntoConjunctsRule());
+ NORMALIZATION.add(new IntroduceAggregateCombinerRule());
+ NORMALIZATION.add(new PushSelectIntoJoinRule());
+ NORMALIZATION.add(new ExtractGbyExpressionsRule());
+ NORMALIZATION.add(new RemoveRedundantSelectRule());
+ }
+
+ public final static LinkedList<IAlgebraicRewriteRule> COND_PUSHDOWN_AND_JOIN_INFERENCE = new LinkedList<IAlgebraicRewriteRule>();
+ static {
+ COND_PUSHDOWN_AND_JOIN_INFERENCE.add(new PushSelectDownRule());
+ COND_PUSHDOWN_AND_JOIN_INFERENCE.add(new InlineVariablesRule());
+ COND_PUSHDOWN_AND_JOIN_INFERENCE.add(new FactorRedundantGroupAndDecorVarsRule());
+ COND_PUSHDOWN_AND_JOIN_INFERENCE.add(new EliminateSubplanRule());
+ }
+
+ public final static LinkedList<IAlgebraicRewriteRule> LOAD_FIELDS = new LinkedList<IAlgebraicRewriteRule>();
+ static {
+ // should LoadRecordFieldsRule be applied in only one pass over the
+ // plan?
+ LOAD_FIELDS.add(new InlineVariablesRule());
+ // LOAD_FIELDS.add(new RemoveUnusedAssignAndAggregateRule());
+ LOAD_FIELDS.add(new ComplexJoinInferenceRule());
+ LOAD_FIELDS.add(new InferTypesRule());
+ }
+
+ public final static LinkedList<IAlgebraicRewriteRule> OP_PUSHDOWN = new LinkedList<IAlgebraicRewriteRule>();
+ static {
+ OP_PUSHDOWN.add(new PushProjectDownRule());
+ OP_PUSHDOWN.add(new PushSelectDownRule());
+ }
+
+ public final static LinkedList<IAlgebraicRewriteRule> DATA_EXCHANGE = new LinkedList<IAlgebraicRewriteRule>();
+ static {
+ DATA_EXCHANGE.add(new SetExecutionModeRule());
+ }
+
+ public final static LinkedList<IAlgebraicRewriteRule> CONSOLIDATION = new LinkedList<IAlgebraicRewriteRule>();
+ static {
+ CONSOLIDATION.add(new RemoveRedundantProjectionRule());
+ CONSOLIDATION.add(new ConsolidateSelectsRule());
+ CONSOLIDATION.add(new IntroduceEarlyProjectRule());
+ CONSOLIDATION.add(new ConsolidateAssignsRule());
+ CONSOLIDATION.add(new IntroduceGroupByCombinerRule());
+ CONSOLIDATION.add(new RemoveUnusedAssignAndAggregateRule());
+ }
+
+ public final static LinkedList<IAlgebraicRewriteRule> PHYSICAL_PLAN_REWRITES = new LinkedList<IAlgebraicRewriteRule>();
+ static {
+ PHYSICAL_PLAN_REWRITES.add(new PullSelectOutOfEqJoin());
+ PHYSICAL_PLAN_REWRITES.add(new SetAlgebricksPhysicalOperatorsRule());
+ PHYSICAL_PLAN_REWRITES.add(new EnforceStructuralPropertiesRule());
+ PHYSICAL_PLAN_REWRITES.add(new PushProjectDownRule());
+ PHYSICAL_PLAN_REWRITES.add(new SetAlgebricksPhysicalOperatorsRule());
+ PHYSICAL_PLAN_REWRITES.add(new PushLimitDownRule());
+ PHYSICAL_PLAN_REWRITES.add(new InsertProjectBeforeWriteRule());
+ PHYSICAL_PLAN_REWRITES.add(new InsertProjectBeforeUnionRule());
+ }
+
+ public final static LinkedList<IAlgebraicRewriteRule> prepareJobGenRules = new LinkedList<IAlgebraicRewriteRule>();
+ static {
+ prepareJobGenRules.add(new ReinferAllTypesRule());
+ prepareJobGenRules.add(new IsolateHyracksOperatorsRule(
+ HeuristicOptimizer.hyraxOperatorsBelowWhichJobGenIsDisabled));
+ prepareJobGenRules.add(new ExtractCommonOperatorsRule());
+ prepareJobGenRules.add(new LocalGroupByRule());
+ prepareJobGenRules.add(new PushProjectIntoDataSourceScanRule());
+ prepareJobGenRules.add(new ReinferAllTypesRule());
+ }
+
+}
diff --git a/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/InsertProjectBeforeWriteRule.java b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/InsertProjectBeforeWriteRule.java
new file mode 100644
index 0000000..90777ee
--- /dev/null
+++ b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/InsertProjectBeforeWriteRule.java
@@ -0,0 +1,79 @@
+package edu.uci.ics.hivesterix.optimizer.rules;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.commons.lang3.mutable.Mutable;
+import org.apache.commons.lang3.mutable.MutableObject;
+
+import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.IOptimizationContext;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalOperatorTag;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalVariable;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator.ExecutionMode;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.ProjectOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.WriteOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.visitors.VariableUtilities;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.physical.StreamProjectPOperator;
+import edu.uci.ics.hyracks.algebricks.core.rewriter.base.IAlgebraicRewriteRule;
+
+public class InsertProjectBeforeWriteRule implements IAlgebraicRewriteRule {
+
+ @Override
+ public boolean rewritePost(Mutable<ILogicalOperator> opRef, IOptimizationContext context) {
+ return false;
+ }
+
+ /**
+ * When the input schema to WriteOperator is different from the output
+ * schema in terms of variable order, add a project operator to get the
+ * write order
+ */
+ @Override
+ public boolean rewritePre(Mutable<ILogicalOperator> opRef, IOptimizationContext context) throws AlgebricksException {
+ AbstractLogicalOperator op = (AbstractLogicalOperator) opRef.getValue();
+ if (op.getOperatorTag() != LogicalOperatorTag.WRITE) {
+ return false;
+ }
+ WriteOperator opWrite = (WriteOperator) op;
+ ArrayList<LogicalVariable> finalSchema = new ArrayList<LogicalVariable>();
+ VariableUtilities.getUsedVariables(opWrite, finalSchema);
+ ArrayList<LogicalVariable> inputSchema = new ArrayList<LogicalVariable>();
+ VariableUtilities.getLiveVariables(opWrite, inputSchema);
+ if (!isIdentical(finalSchema, inputSchema)) {
+ ProjectOperator projectOp = new ProjectOperator(finalSchema);
+ Mutable<ILogicalOperator> parentOpRef = opWrite.getInputs().get(0);
+ projectOp.getInputs().add(parentOpRef);
+ opWrite.getInputs().clear();
+ opWrite.getInputs().add(new MutableObject<ILogicalOperator>(projectOp));
+ projectOp.setPhysicalOperator(new StreamProjectPOperator());
+ projectOp.setExecutionMode(ExecutionMode.PARTITIONED);
+
+ AbstractLogicalOperator op2 = (AbstractLogicalOperator) parentOpRef.getValue();
+ if (op2.getOperatorTag() == LogicalOperatorTag.PROJECT) {
+ ProjectOperator pi2 = (ProjectOperator) op2;
+ parentOpRef.setValue(pi2.getInputs().get(0).getValue());
+ }
+ context.computeAndSetTypeEnvironmentForOperator(projectOp);
+ return true;
+ } else
+ return false;
+
+ }
+
+ private boolean isIdentical(List<LogicalVariable> finalSchema, List<LogicalVariable> inputSchema) {
+ int finalSchemaSize = finalSchema.size();
+ int inputSchemaSize = inputSchema.size();
+ if (finalSchemaSize != inputSchemaSize)
+ throw new IllegalStateException("final output schema variables missing!");
+ for (int i = 0; i < finalSchemaSize; i++) {
+ LogicalVariable var1 = finalSchema.get(i);
+ LogicalVariable var2 = inputSchema.get(i);
+ if (!var1.equals(var2))
+ return false;
+ }
+ return true;
+ }
+}
diff --git a/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/IntroduceEarlyProjectRule.java b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/IntroduceEarlyProjectRule.java
new file mode 100644
index 0000000..0a18629
--- /dev/null
+++ b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/IntroduceEarlyProjectRule.java
@@ -0,0 +1,73 @@
+package edu.uci.ics.hivesterix.optimizer.rules;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.apache.commons.lang3.mutable.Mutable;
+import org.apache.commons.lang3.mutable.MutableObject;
+
+import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.IOptimizationContext;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalOperatorTag;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalVariable;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.ProjectOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.visitors.VariableUtilities;
+import edu.uci.ics.hyracks.algebricks.core.rewriter.base.IAlgebraicRewriteRule;
+
+public class IntroduceEarlyProjectRule implements IAlgebraicRewriteRule {
+
+ @Override
+ public boolean rewritePre(Mutable<ILogicalOperator> opRef, IOptimizationContext context) throws AlgebricksException {
+ return false;
+ }
+
+ @Override
+ public boolean rewritePost(Mutable<ILogicalOperator> opRef, IOptimizationContext context)
+ throws AlgebricksException {
+ AbstractLogicalOperator op = (AbstractLogicalOperator) opRef.getValue();
+ if (op.getOperatorTag() != LogicalOperatorTag.PROJECT) {
+ return false;
+ }
+ AbstractLogicalOperator middleOp = (AbstractLogicalOperator) op.getInputs().get(0).getValue();
+ List<LogicalVariable> deliveredVars = new ArrayList<LogicalVariable>();
+ List<LogicalVariable> usedVars = new ArrayList<LogicalVariable>();
+ List<LogicalVariable> producedVars = new ArrayList<LogicalVariable>();
+
+ VariableUtilities.getUsedVariables(op, deliveredVars);
+ VariableUtilities.getUsedVariables(middleOp, usedVars);
+ VariableUtilities.getProducedVariables(middleOp, producedVars);
+
+ Set<LogicalVariable> requiredVariables = new HashSet<LogicalVariable>();
+ requiredVariables.addAll(deliveredVars);
+ requiredVariables.addAll(usedVars);
+ requiredVariables.removeAll(producedVars);
+
+ if (middleOp.getInputs().size() <= 0 || middleOp.getInputs().size() > 1)
+ return false;
+
+ AbstractLogicalOperator targetOp = (AbstractLogicalOperator) middleOp.getInputs().get(0).getValue();
+ if (targetOp.getOperatorTag() != LogicalOperatorTag.DATASOURCESCAN)
+ return false;
+
+ Set<LogicalVariable> deliveredEarlyVars = new HashSet<LogicalVariable>();
+ VariableUtilities.getLiveVariables(targetOp, deliveredEarlyVars);
+
+ deliveredEarlyVars.removeAll(requiredVariables);
+ if (deliveredEarlyVars.size() > 0) {
+ ArrayList<LogicalVariable> requiredVars = new ArrayList<LogicalVariable>();
+ requiredVars.addAll(requiredVariables);
+ ILogicalOperator earlyProjectOp = new ProjectOperator(requiredVars);
+ Mutable<ILogicalOperator> earlyProjectOpRef = new MutableObject<ILogicalOperator>(earlyProjectOp);
+ Mutable<ILogicalOperator> targetRef = middleOp.getInputs().get(0);
+ middleOp.getInputs().set(0, earlyProjectOpRef);
+ earlyProjectOp.getInputs().add(targetRef);
+ context.computeAndSetTypeEnvironmentForOperator(earlyProjectOp);
+ return true;
+ }
+ return false;
+ }
+}
diff --git a/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/LocalGroupByRule.java b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/LocalGroupByRule.java
new file mode 100644
index 0000000..90ca008
--- /dev/null
+++ b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/LocalGroupByRule.java
@@ -0,0 +1,66 @@
+package edu.uci.ics.hivesterix.optimizer.rules;
+
+import org.apache.commons.lang3.mutable.Mutable;
+
+import edu.uci.ics.hivesterix.logical.plan.HiveOperatorAnnotations;
+import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.IOptimizationContext;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.IPhysicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalOperatorTag;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.OperatorAnnotations;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.PhysicalOperatorTag;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.ExchangeOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.physical.OneToOneExchangePOperator;
+import edu.uci.ics.hyracks.algebricks.core.rewriter.base.IAlgebraicRewriteRule;
+
+public class LocalGroupByRule implements IAlgebraicRewriteRule {
+
+ @Override
+ public boolean rewritePre(Mutable<ILogicalOperator> opRef, IOptimizationContext context) throws AlgebricksException {
+ return false;
+ }
+
+ @Override
+ public boolean rewritePost(Mutable<ILogicalOperator> opRef, IOptimizationContext context)
+ throws AlgebricksException {
+ AbstractLogicalOperator op = (AbstractLogicalOperator) opRef.getValue();
+ if (op.getOperatorTag() != LogicalOperatorTag.GROUP) {
+ return false;
+ }
+ Boolean localGby = (Boolean) op.getAnnotations().get(HiveOperatorAnnotations.LOCAL_GROUP_BY);
+ if (localGby != null && localGby.equals(Boolean.TRUE)) {
+ Boolean hashGby = (Boolean) op.getAnnotations().get(OperatorAnnotations.USE_HASH_GROUP_BY);
+ Boolean externalGby = (Boolean) op.getAnnotations().get(OperatorAnnotations.USE_EXTERNAL_GROUP_BY);
+ if ((hashGby != null && (hashGby.equals(Boolean.TRUE)) || (externalGby != null && externalGby
+ .equals(Boolean.TRUE)))) {
+ reviseExchange(op);
+ } else {
+ ILogicalOperator child = op.getInputs().get(0).getValue();
+ AbstractLogicalOperator childOp = (AbstractLogicalOperator) child;
+ while (child.getInputs().size() > 0) {
+ if (childOp.getOperatorTag() == LogicalOperatorTag.ORDER)
+ break;
+ else {
+ child = child.getInputs().get(0).getValue();
+ childOp = (AbstractLogicalOperator) child;
+ }
+ }
+ if (childOp.getOperatorTag() == LogicalOperatorTag.ORDER)
+ reviseExchange(childOp);
+ }
+ return true;
+ }
+ return false;
+ }
+
+ private void reviseExchange(AbstractLogicalOperator op) {
+ ExchangeOperator exchange = (ExchangeOperator) op.getInputs().get(0).getValue();
+ IPhysicalOperator physicalOp = exchange.getPhysicalOperator();
+ if (physicalOp.getOperatorTag() == PhysicalOperatorTag.HASH_PARTITION_EXCHANGE) {
+ exchange.setPhysicalOperator(new OneToOneExchangePOperator());
+ }
+ }
+
+}
diff --git a/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/RemoveRedundantSelectRule.java b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/RemoveRedundantSelectRule.java
new file mode 100644
index 0000000..44ff12d
--- /dev/null
+++ b/fullstack/hivesterix/hivesterix-optimizer/src/main/java/edu/uci/ics/hivesterix/optimizer/rules/RemoveRedundantSelectRule.java
@@ -0,0 +1,44 @@
+package edu.uci.ics.hivesterix.optimizer.rules;
+
+import org.apache.commons.lang3.mutable.Mutable;
+
+import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalExpression;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.IOptimizationContext;
+import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalOperatorTag;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.SelectOperator;
+import edu.uci.ics.hyracks.algebricks.core.rewriter.base.IAlgebraicRewriteRule;
+
+public class RemoveRedundantSelectRule implements IAlgebraicRewriteRule {
+
+ @Override
+ public boolean rewritePre(Mutable<ILogicalOperator> opRef, IOptimizationContext context) throws AlgebricksException {
+ return false;
+ }
+
+ @Override
+ public boolean rewritePost(Mutable<ILogicalOperator> opRef, IOptimizationContext context)
+ throws AlgebricksException {
+ AbstractLogicalOperator op = (AbstractLogicalOperator) opRef.getValue();
+ if (op.getOperatorTag() != LogicalOperatorTag.SELECT) {
+ return false;
+ }
+ AbstractLogicalOperator inputOp = (AbstractLogicalOperator) op.getInputs().get(0).getValue();
+ if (inputOp.getOperatorTag() != LogicalOperatorTag.SELECT) {
+ return false;
+ }
+ SelectOperator selectOp = (SelectOperator) op;
+ SelectOperator inputSelectOp = (SelectOperator) inputOp;
+ ILogicalExpression expr1 = selectOp.getCondition().getValue();
+ ILogicalExpression expr2 = inputSelectOp.getCondition().getValue();
+
+ if (expr1.equals(expr2)) {
+ selectOp.getInputs().set(0, inputSelectOp.getInputs().get(0));
+ return true;
+ }
+ return false;
+ }
+
+}