amansinha100 commented on a change in pull request #1347: DRILL-6545: Projection Push down into Lateral Join operator. URL: https://github.com/apache/drill/pull/1347#discussion_r199020924
########## File path: exec/java-exec/src/main/java/org/apache/drill/exec/planner/logical/DrillProjectPushIntoLateralJoinRule.java ########## @@ -0,0 +1,113 @@ +/* + * 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.drill.exec.planner.logical; + +import org.apache.calcite.plan.RelOptRule; +import org.apache.calcite.plan.RelOptRuleCall; +import org.apache.calcite.plan.RelTraitSet; +import org.apache.calcite.rel.RelNode; +import org.apache.calcite.rel.core.RelFactories; +import org.apache.calcite.rex.RexBuilder; +import org.apache.calcite.rex.RexInputRef; +import org.apache.calcite.rex.RexNode; +import org.apache.calcite.tools.RelBuilderFactory; +import org.apache.commons.collections.map.HashedMap; +import org.apache.drill.exec.planner.StarColumnHelper; +import org.apache.drill.exec.planner.common.DrillRelOptUtil; + +import java.util.ArrayList; +import java.util.List; +import java.util.Map; + + +public class DrillProjectPushIntoLateralJoinRule extends RelOptRule { + + public static final DrillProjectPushIntoLateralJoinRule INSTANCE = + new DrillProjectPushIntoLateralJoinRule(RelFactories.LOGICAL_BUILDER); + + + public DrillProjectPushIntoLateralJoinRule(RelBuilderFactory relFactory) { + super(operand(DrillProjectRel.class, + operand(DrillLateralJoinRel.class, any())), + relFactory, null); + } + + public void onMatch(RelOptRuleCall call) { + DrillProjectRel origProj = call.rel(0); + final DrillLateralJoinRel corr = call.rel(1); + + if (StarColumnHelper.containsStarColumn(origProj.getRowType()) || + StarColumnHelper.containsStarColumn(corr.getRowType()) || + corr.excludeCorrelateColumn) { + return; + } + DrillRelOptUtil.InputRefVisitor collectRefs = new DrillRelOptUtil.InputRefVisitor(); + for (RexNode exp: origProj.getChildExps()) { + exp.accept(collectRefs); + } + + int correlationIndex = corr.getRequiredColumns().nextSetBit(0); + for (RexInputRef inputRef : collectRefs.getInputRefs()) { + if (inputRef.getIndex() == correlationIndex) { + return; + } + } + + final RelNode left = corr.getLeft(); + final RelNode right = corr.getRight(); + final RelNode convertedLeft = convert(left, left.getTraitSet().plus(DrillRel.DRILL_LOGICAL).simplify()); + final RelNode convertedRight = convert(right, right.getTraitSet().plus(DrillRel.DRILL_LOGICAL).simplify()); + + final RelTraitSet traits = corr.getTraitSet().plus(DrillRel.DRILL_LOGICAL); + RelNode relNode = new DrillLateralJoinRel(corr.getCluster(), + traits, convertedLeft, convertedRight, true, corr.getCorrelationId(), + corr.getRequiredColumns(), corr.getJoinType()); + + if (!DrillRelOptUtil.isTrivialProject(origProj, true)) { + Map<Integer, Integer> mapWithoutCorr = buildMapWithoutCorrColumn(corr, correlationIndex); + List<RexNode> outputExprs = transformExprs(origProj.getCluster().getRexBuilder(), origProj.getChildExps(), mapWithoutCorr); + + relNode = new DrillProjectRel(origProj.getCluster(), + left.getTraitSet().plus(DrillRel.DRILL_LOGICAL), + relNode, outputExprs, origProj.getRowType()); + } + call.transformTo(relNode); + } + + private List<RexNode> transformExprs(RexBuilder builder, List<RexNode> exprs, Map<Integer, Integer> corrMap) { + List<RexNode> outputExprs = new ArrayList<>(); + DrillRelOptUtil.RexFieldsTransformer transformer = new DrillRelOptUtil.RexFieldsTransformer(builder, corrMap); + for (RexNode expr : exprs) { + outputExprs.add(transformer.go(expr)); + } + return outputExprs; + } + + private Map<Integer, Integer> buildMapWithoutCorrColumn(RelNode corr, int correlationIndex) { + int index = 0; + Map<Integer, Integer> result = new HashedMap(); Review comment: Any reason for using a HashedMap instead of just HashMap ? (unless you are using the MapIterator it seems the latter should suffice). ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
