Added missing rule file.
git-svn-id: https://asterixdb.googlecode.com/svn/branches/asterix_fuzzy_perf@886 eaa15691-b419-025a-1212-ee371bd00084
diff --git a/asterix-algebra/src/main/java/edu/uci/ics/asterix/optimizer/rules/PushSimilarityFunctionsBelowJoin.java b/asterix-algebra/src/main/java/edu/uci/ics/asterix/optimizer/rules/PushSimilarityFunctionsBelowJoin.java
new file mode 100644
index 0000000..69a5fb5
--- /dev/null
+++ b/asterix-algebra/src/main/java/edu/uci/ics/asterix/optimizer/rules/PushSimilarityFunctionsBelowJoin.java
@@ -0,0 +1,214 @@
+/*
+ * Copyright 2009-2012 by The Regents of the University of California
+ * Licensed 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 from
+ *
+ * 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 edu.uci.ics.asterix.optimizer.rules;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.Iterator;
+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.asterix.om.functions.AsterixBuiltinFunctions;
+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.LogicalExpressionTag;
+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.expressions.AbstractFunctionCallExpression;
+import edu.uci.ics.hyracks.algebricks.core.algebra.expressions.AbstractLogicalExpression;
+import edu.uci.ics.hyracks.algebricks.core.algebra.expressions.VariableReferenceExpression;
+import edu.uci.ics.hyracks.algebricks.core.algebra.functions.FunctionIdentifier;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractBinaryJoinOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AssignOperator;
+import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.visitors.VariableUtilities;
+import edu.uci.ics.hyracks.algebricks.core.rewriter.base.IAlgebraicRewriteRule;
+
+/**
+ * Pushes similarity function-call expressions below a join if possible.
+ * Assigns the similarity function-call expressions to new variables, and replaces the original
+ * expression with a corresponding variable reference expression.
+ * This rule can help reduce the cost of computing expensive similarity functions by pushing them below
+ * a join (which may blow up the cardinality).
+ * Also, this rule may help to enable other rules such as common subexpression elimination, again to reduce
+ * the number of calls to expensive similarity functions.
+ *
+ * Example:
+ *
+ * Before plan:
+ * assign [$$10] <- [funcA(funcB(simFuncX($$3, $$4)))]
+ * join (some condition)
+ * join_branch_0 where $$3 and $$4 are not live
+ * ...
+ * join_branch_1 where $$3 and $$4 are live
+ * ...
+ *
+ * After plan:
+ * assign [$$10] <- [funcA(funcB($$11))]
+ * join (some condition)
+ * join_branch_0 where $$3 and $$4 are not live
+ * ...
+ * join_branch_1 where $$3 and $$4 are live
+ * assign[$$11] <- [simFuncX($$3, $$4)]
+ * ...
+ */
+public class PushSimilarityFunctionsBelowJoin implements IAlgebraicRewriteRule {
+
+ private static final Set<FunctionIdentifier> simFuncIdents = new HashSet<FunctionIdentifier>();
+ static {
+ simFuncIdents.add(AsterixBuiltinFunctions.SIMILARITY_JACCARD);
+ simFuncIdents.add(AsterixBuiltinFunctions.SIMILARITY_JACCARD_CHECK);
+ simFuncIdents.add(AsterixBuiltinFunctions.EDIT_DISTANCE);
+ simFuncIdents.add(AsterixBuiltinFunctions.EDIT_DISTANCE_CHECK);
+ }
+
+ private final List<Mutable<ILogicalExpression>> simFuncExprs = new ArrayList<Mutable<ILogicalExpression>>();
+ private final List<LogicalVariable> usedVars = new ArrayList<LogicalVariable>();
+ private final List<LogicalVariable> liveVars = new ArrayList<LogicalVariable>();
+
+ @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.ASSIGN) {
+ return false;
+ }
+ AssignOperator assignOp = (AssignOperator) op;
+
+ // Find a join operator below this assign.
+ Mutable<ILogicalOperator> joinOpRef = findJoinOp(assignOp.getInputs().get(0));
+ if (joinOpRef == null) {
+ return false;
+ }
+ AbstractBinaryJoinOperator joinOp = (AbstractBinaryJoinOperator) joinOpRef.getValue();
+
+ // Check if the assign uses a similarity function that we wish to push below the join if possible.
+ simFuncExprs.clear();
+ gatherSimilarityFunctionCalls(assignOp, simFuncExprs);
+ if (simFuncExprs.isEmpty()) {
+ return false;
+ }
+
+ // Try to push the similarity functions down the input branches of the join.
+ boolean modified = false;
+ if (pushDownSimilarityFunctions(joinOp, 0, simFuncExprs, context)) {
+ modified = true;
+ }
+ if (pushDownSimilarityFunctions(joinOp, 1, simFuncExprs, context)) {
+ modified = true;
+ }
+ if (modified) {
+ context.computeAndSetTypeEnvironmentForOperator(joinOp);
+ }
+ return modified;
+ }
+
+ private Mutable<ILogicalOperator> findJoinOp(Mutable<ILogicalOperator> opRef) {
+ AbstractLogicalOperator op = (AbstractLogicalOperator) opRef.getValue();
+ switch (op.getOperatorTag()) {
+ case INNERJOIN:
+ case LEFTOUTERJOIN: {
+ return opRef;
+ }
+ // Bail on these operators.
+ case GROUP:
+ case AGGREGATE:
+ case DISTINCT:
+ case UNNEST_MAP: {
+ return null;
+ }
+ // Traverse children.
+ default: {
+ for (Mutable<ILogicalOperator> childOpRef : op.getInputs()) {
+ return findJoinOp(childOpRef);
+ }
+ }
+ }
+ return null;
+ }
+
+ private void gatherSimilarityFunctionCalls(AssignOperator assignOp, List<Mutable<ILogicalExpression>> simFuncExprs) {
+ for (Mutable<ILogicalExpression> exprRef : assignOp.getExpressions()) {
+ gatherSimilarityFunctionCalls(exprRef, simFuncExprs);
+ }
+ }
+
+ private void gatherSimilarityFunctionCalls(Mutable<ILogicalExpression> exprRef,
+ List<Mutable<ILogicalExpression>> simFuncExprs) {
+ AbstractLogicalExpression expr = (AbstractLogicalExpression) exprRef.getValue();
+ if (expr.getExpressionTag() != LogicalExpressionTag.FUNCTION_CALL) {
+ return;
+ }
+ // Check whether the function is a similarity function.
+ AbstractFunctionCallExpression funcExpr = (AbstractFunctionCallExpression) expr;
+ if (simFuncIdents.contains(funcExpr.getFunctionIdentifier())) {
+ simFuncExprs.add(exprRef);
+ }
+ // Traverse arguments.
+ for (Mutable<ILogicalExpression> funcArg : funcExpr.getArguments()) {
+ gatherSimilarityFunctionCalls(funcArg, simFuncExprs);
+ }
+ }
+
+ private boolean pushDownSimilarityFunctions(AbstractBinaryJoinOperator joinOp, int inputIndex,
+ List<Mutable<ILogicalExpression>> simFuncExprs, IOptimizationContext context) throws AlgebricksException {
+ ILogicalOperator joinInputOp = joinOp.getInputs().get(inputIndex).getValue();
+ liveVars.clear();
+ VariableUtilities.getLiveVariables(joinInputOp, liveVars);
+ Iterator<Mutable<ILogicalExpression>> simFuncIter = simFuncExprs.iterator();
+ List<LogicalVariable> assignVars = null;
+ List<Mutable<ILogicalExpression>> assignExprs = null;
+ while (simFuncIter.hasNext()) {
+ Mutable<ILogicalExpression> simFuncExprRef = simFuncIter.next();
+ ILogicalExpression simFuncExpr = simFuncExprRef.getValue();
+ usedVars.clear();
+ simFuncExpr.getUsedVariables(usedVars);
+ // Check if we can push the similarity function down this branch.
+ if (liveVars.containsAll(usedVars)) {
+ if (assignVars == null) {
+ assignVars = new ArrayList<LogicalVariable>();
+ assignExprs = new ArrayList<Mutable<ILogicalExpression>>();
+ }
+ // Replace the original expression with a variable reference expression.
+ LogicalVariable replacementVar = context.newVar();
+ assignVars.add(replacementVar);
+ assignExprs.add(new MutableObject<ILogicalExpression>(simFuncExpr));
+ simFuncExprRef.setValue(new VariableReferenceExpression(replacementVar));
+ simFuncIter.remove();
+ }
+ }
+ // Create new assign operator below the join if any similarity functions can be pushed.
+ if (assignVars != null) {
+ AssignOperator newAssign = new AssignOperator(assignVars, assignExprs);
+ newAssign.getInputs().add(new MutableObject<ILogicalOperator>(joinInputOp));
+ newAssign.setExecutionMode(joinOp.getExecutionMode());
+ joinOp.getInputs().get(inputIndex).setValue(newAssign);
+ context.computeAndSetTypeEnvironmentForOperator(newAssign);
+ return true;
+ }
+ return false;
+ }
+}
diff --git a/asterix-app/src/test/resources/optimizerts/only.txt b/asterix-app/src/test/resources/optimizerts/only.txt
index 529ccf8..e69de29 100644
--- a/asterix-app/src/test/resources/optimizerts/only.txt
+++ b/asterix-app/src/test/resources/optimizerts/only.txt
@@ -1 +0,0 @@
-inverted-index-join/ngram-edit-distance_04.aql
\ No newline at end of file