maheshk114 commented on a change in pull request #1147: URL: https://github.com/apache/hive/pull/1147#discussion_r459998845
########## File path: ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveJoinWithFilterToAntiJoinRule.java ########## @@ -0,0 +1,145 @@ +/* + * 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.rel.type.RelDataTypeField; +import org.apache.calcite.rex.RexInputRef; +import org.apache.calcite.rex.RexNode; +import org.apache.calcite.sql.SqlKind; +import org.apache.calcite.util.ImmutableBitSet; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.util.ArrayList; +import java.util.List; + +/** + * Planner rule that converts a join plus filter to anti join. + */ +public class HiveJoinWithFilterToAntiJoinRule extends RelOptRule { + protected static final Logger LOG = LoggerFactory.getLogger(HiveJoinWithFilterToAntiJoinRule.class); + public static final HiveJoinWithFilterToAntiJoinRule INSTANCE = new HiveJoinWithFilterToAntiJoinRule(); + + // 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 HiveJoinWithFilterToAntiJoinRule() { + 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("Matched HiveAntiJoinRule"); + + assert (filter != null); + + //We support conversion from left outer join only. + if (join.getJoinType() != JoinRelType.LEFT) { + return; + } + + List<RexNode> aboveFilters = RelOptUtil.conjunctions(filter.getCondition()); + boolean hasIsNull = false; + + // Get all filter condition and check if any of them is a "is null" kind. + for (RexNode filterNode : aboveFilters) { + if (filterNode.getKind() == SqlKind.IS_NULL && + isFilterFromRightSide(join, filterNode, join.getJoinType())) { + hasIsNull = true; + break; + } + } + + // Is null should be on a key from right side of the join. + if (!hasIsNull) { + return; + } + + // Build anti join with same left, right child and condition as original left outer join. + Join anti = join.copy(join.getTraitSet(), join.getCondition(), Review comment: done ---------------------------------------------------------------- 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
