maheshk114 commented on a change in pull request #1147: URL: https://github.com/apache/hive/pull/1147#discussion_r466819149
########## File path: ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveAntiSemiJoinRule.java ########## @@ -0,0 +1,105 @@ +/* + * 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.hadoop.hive.ql.optimizer.calcite.rules; + +import org.apache.calcite.plan.RelOptRule; +import org.apache.calcite.plan.RelOptRuleCall; +import org.apache.calcite.plan.RelOptUtil; +import org.apache.calcite.rel.RelNode; +import org.apache.calcite.rel.core.Filter; +import org.apache.calcite.rel.core.Join; +import org.apache.calcite.rel.core.JoinRelType; +import org.apache.calcite.rel.core.Project; +import org.apache.calcite.rex.RexNode; +import org.apache.calcite.sql.SqlKind; +import org.apache.hadoop.hive.ql.optimizer.calcite.HiveCalciteUtil; +import org.apache.hadoop.hive.ql.optimizer.calcite.reloperators.HiveAntiJoin; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.util.List; +import java.util.stream.Collectors; +import java.util.stream.Stream; + +/** + * Planner rule that converts a join plus filter to anti join. + */ +public class HiveAntiSemiJoinRule extends RelOptRule { + protected static final Logger LOG = LoggerFactory.getLogger(HiveAntiSemiJoinRule.class); + public static final HiveAntiSemiJoinRule INSTANCE = new HiveAntiSemiJoinRule(); + + // HiveProject(fld=[$0]) + // HiveFilter(condition=[IS NULL($1)]) + // HiveJoin(condition=[=($0, $1)], joinType=[left], algorithm=[none], cost=[not available]) + // + // TO + // + // HiveProject(fld_tbl=[$0]) + // HiveAntiJoin(condition=[=($0, $1)], joinType=[anti]) + // + public HiveAntiSemiJoinRule() { + super(operand(Project.class, operand(Filter.class, operand(Join.class, RelOptRule.any()))), + "HiveJoinWithFilterToAntiJoinRule:filter"); + } + + // is null filter over a left join. + public void onMatch(final RelOptRuleCall call) { + final Project project = call.rel(0); + final Filter filter = call.rel(1); + final Join join = call.rel(2); + perform(call, project, filter, join); + } + + protected void perform(RelOptRuleCall call, Project project, Filter filter, Join join) { + LOG.debug("Start Matching HiveAntiJoinRule"); + + //TODO : Need to support this scenario. + if (join.getCondition().isAlwaysTrue()) { + return; + } + + //We support conversion from left outer join only. + if (join.getJoinType() != JoinRelType.LEFT) { + return; + } + + assert (filter != null); + + // If null filter is not present from right side then we can not convert to anti join. + List<RexNode> aboveFilters = RelOptUtil.conjunctions(filter.getCondition()); + Stream<RexNode> nullFilters = aboveFilters.stream().filter(filterNode -> filterNode.getKind() == SqlKind.IS_NULL); + boolean hasNullFilter = HiveCalciteUtil.hasAnyExpressionFromRightSide(join, nullFilters.collect(Collectors.toList())); + if (!hasNullFilter) { + return; + } + + // If any projection is there from right side, then we can not convert to anti join. + boolean hasProjection = HiveCalciteUtil.hasAnyExpressionFromRightSide(join, project.getProjects()); + if (hasProjection) { + return; + } + + LOG.debug("Matched HiveAntiJoinRule"); + + // Build anti join with same left, right child and condition as original left outer join. + Join anti = HiveAntiJoin.getAntiJoin(join.getLeft().getCluster(), join.getLeft().getTraitSet(), + join.getLeft(), join.getRight(), join.getCondition()); + RelNode newProject = project.copy(project.getTraitSet(), anti, project.getProjects(), project.getRowType()); + call.transformTo(newProject); Review comment: for normal filter, its being pushed down. here we get filters which can not be pushed down. I have modified the code to handle those filters. And added these extra tests to verify. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to 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 --------------------------------------------------------------------- To unsubscribe, e-mail: gitbox-unsubscr...@hive.apache.org For additional commands, e-mail: gitbox-h...@hive.apache.org
