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* 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.
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package org.apache.hadoop.hive.ql.optimizer.calcite.rules;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.apache.calcite.plan.RelOptCluster;
import org.apache.calcite.plan.RelOptRule;
import org.apache.calcite.plan.RelOptRuleCall;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.core.Join;
import org.apache.calcite.rel.core.JoinRelType;
import org.apache.calcite.rel.core.RelFactories;
import org.apache.calcite.rel.core.RelFactories.FilterFactory;
import org.apache.calcite.rel.type.RelDataType;
import org.apache.calcite.rex.RexBuilder;
import org.apache.calcite.rex.RexNode;
import org.apache.calcite.rex.RexUtil;
import org.apache.calcite.sql.fun.SqlStdOperatorTable;
import org.apache.hadoop.hive.ql.optimizer.calcite.CalciteSemanticException;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveCalciteUtil;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveCalciteUtil.JoinLeafPredicateInfo;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveCalciteUtil.JoinPredicateInfo;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveRelFactories;
import org.apache.hadoop.hive.ql.optimizer.calcite.reloperators.HiveJoin;
import org.apache.hadoop.hive.ql.optimizer.calcite.reloperators.HiveSemiJoin;
import com.google.common.collect.Lists;
import com.google.common.collect.Sets;
public final class HiveJoinAddNotNullRule extends RelOptRule {
public static final HiveJoinAddNotNullRule INSTANCE_JOIN =
new HiveJoinAddNotNullRule(HiveJoin.class, HiveRelFactories.HIVE_FILTER_FACTORY);
public static final HiveJoinAddNotNullRule INSTANCE_SEMIJOIN =
new HiveJoinAddNotNullRule(HiveSemiJoin.class, HiveRelFactories.HIVE_FILTER_FACTORY);
private final FilterFactory filterFactory;
//~ Constructors -----------------------------------------------------------
/**
* Creates an HiveJoinAddNotNullRule.
*/
public HiveJoinAddNotNullRule(Class<? extends Join> clazz,
RelFactories.FilterFactory filterFactory) {
super(operand(clazz, any()));
this.filterFactory = filterFactory;
}
//~ Methods ----------------------------------------------------------------
@Override
public void onMatch(RelOptRuleCall call) {
final Join join = call.rel(0);
RelNode lChild = join.getLeft();
RelNode rChild = join.getRight();
HiveRulesRegistry registry = call.getPlanner().getContext().unwrap(HiveRulesRegistry.class);
assert registry != null;
if (join.getJoinType() != JoinRelType.INNER) {
return;
}
if (join.getCondition().isAlwaysTrue()) {
return;
}
JoinPredicateInfo joinPredInfo;
try {
joinPredInfo = HiveCalciteUtil.JoinPredicateInfo.constructJoinPredicateInfo(join);
} catch (CalciteSemanticException e) {
return;
}
Set<Integer> joinLeftKeyPositions = new HashSet<Integer>();
Set<Integer> joinRightKeyPositions = new HashSet<Integer>();
for (int i = 0; i < joinPredInfo.getEquiJoinPredicateElements().size(); i++) {
JoinLeafPredicateInfo joinLeafPredInfo = joinPredInfo.
getEquiJoinPredicateElements().get(i);
joinLeftKeyPositions.addAll(joinLeafPredInfo.getProjsFromLeftPartOfJoinKeysInChildSchema());
joinRightKeyPositions.addAll(joinLeafPredInfo.getProjsFromRightPartOfJoinKeysInChildSchema());
}
// Build not null conditions
final RelOptCluster cluster = join.getCluster();
final RexBuilder rexBuilder = join.getCluster().getRexBuilder();
Set<String> leftPushedPredicates = Sets.newHashSet(registry.getPushedPredicates(join, 0));
final List<RexNode> newLeftConditions = getNotNullConditions(cluster,
rexBuilder, join.getLeft(), joinLeftKeyPositions, leftPushedPredicates);
Set<String> rightPushedPredicates = Sets.newHashSet(registry.getPushedPredicates(join, 1));
final List<RexNode> newRightConditions = getNotNullConditions(cluster,
rexBuilder, join.getRight(), joinRightKeyPositions, rightPushedPredicates);
// Nothing will be added to the expression
RexNode newLeftPredicate = RexUtil.composeConjunction(rexBuilder, newLeftConditions, false);
RexNode newRightPredicate = RexUtil.composeConjunction(rexBuilder, newRightConditions, false);
if (newLeftPredicate.isAlwaysTrue() && newRightPredicate.isAlwaysTrue()) {
return;
}
if (!newLeftPredicate.isAlwaysTrue()) {
RelNode curr = lChild;
lChild = filterFactory.createFilter(lChild, newLeftPredicate);
call.getPlanner().onCopy(curr, lChild);
}
if (!newRightPredicate.isAlwaysTrue()) {
RelNode curr = rChild;
rChild = filterFactory.createFilter(rChild, newRightPredicate);
call.getPlanner().onCopy(curr, rChild);
}
Join newJoin = join.copy(join.getTraitSet(), join.getCondition(),
lChild, rChild, join.getJoinType(), join.isSemiJoinDone());
call.getPlanner().onCopy(join, newJoin);
// Register information about created predicates
registry.getPushedPredicates(newJoin, 0).addAll(leftPushedPredicates);
registry.getPushedPredicates(newJoin, 1).addAll(rightPushedPredicates);
call.transformTo(newJoin);
}
private static List<RexNode> getNotNullConditions(RelOptCluster cluster,
RexBuilder rexBuilder, RelNode input, Set<Integer> inputKeyPositions,
Set<String> pushedPredicates) {
final List<RexNode> newConditions = Lists.newArrayList();
for (int pos : inputKeyPositions) {
RelDataType keyType = input.getRowType().getFieldList().get(pos).getType();
// Nothing to do if key cannot be null
if (!keyType.isNullable()) {
continue;
}
RexNode cond = rexBuilder.makeCall(SqlStdOperatorTable.IS_NOT_NULL,
rexBuilder.makeInputRef(input, pos));
String digest = cond.toString();
if (pushedPredicates.add(digest)) {
newConditions.add(cond);
}
}
return newConditions;
}
}