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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.ArrayList;
import java.util.List;
import java.util.Set;
import org.apache.calcite.plan.RelOptCluster;
import org.apache.calcite.plan.RelOptPredicateList;
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.RelFactories.FilterFactory;
import org.apache.calcite.rel.metadata.RelMetadataQuery;
import org.apache.calcite.rel.type.RelDataType;
import org.apache.calcite.rel.type.RelDataTypeField;
import org.apache.calcite.rex.RexBuilder;
import org.apache.calcite.rex.RexCall;
import org.apache.calcite.rex.RexInputRef;
import org.apache.calcite.rex.RexNode;
import org.apache.calcite.rex.RexUtil;
import org.apache.calcite.rex.RexVisitorImpl;
import org.apache.calcite.util.Util;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.optimizer.calcite.HiveCalciteUtil;
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 org.apache.hadoop.hive.ql.udf.generic.GenericUDFOPNotNull;
import org.apache.hive.common.util.AnnotationUtils;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Sets;
/**
* Planner rule that infers predicates from on a
* {@link org.apache.calcite.rel.core.Join} and creates
* {@link org.apache.calcite.rel.core.Filter}s if those predicates can be pushed
* to its inputs.
*
* <p>Uses {@link org.apache.calcite.rel.metadata.RelMdPredicates} to infer
* the predicates,
* returns them in a {@link org.apache.calcite.plan.RelOptPredicateList}
* and applies them appropriately.
*/
public class HiveJoinPushTransitivePredicatesRule extends RelOptRule {
public static final HiveJoinPushTransitivePredicatesRule INSTANCE_JOIN =
new HiveJoinPushTransitivePredicatesRule(HiveJoin.class, HiveRelFactories.HIVE_FILTER_FACTORY);
public static final HiveJoinPushTransitivePredicatesRule INSTANCE_SEMIJOIN =
new HiveJoinPushTransitivePredicatesRule(HiveSemiJoin.class, HiveRelFactories.HIVE_FILTER_FACTORY);
private final FilterFactory filterFactory;
public HiveJoinPushTransitivePredicatesRule(Class<? extends Join> clazz,
FilterFactory filterFactory) {
super(operand(clazz, any()));
this.filterFactory = filterFactory;
}
@Override
public void onMatch(RelOptRuleCall call) {
Join join = call.rel(0);
RelOptPredicateList preds = RelMetadataQuery.instance().getPulledUpPredicates(join);
HiveRulesRegistry registry = call.getPlanner().getContext().unwrap(HiveRulesRegistry.class);
assert registry != null;
RexBuilder rB = join.getCluster().getRexBuilder();
RelNode lChild = join.getLeft();
RelNode rChild = join.getRight();
Set<String> leftPushedPredicates = Sets.newHashSet(registry.getPushedPredicates(join, 0));
List<RexNode> leftPreds = getValidPreds(join.getCluster(), lChild,
leftPushedPredicates, preds.leftInferredPredicates, lChild.getRowType());
Set<String> rightPushedPredicates = Sets.newHashSet(registry.getPushedPredicates(join, 1));
List<RexNode> rightPreds = getValidPreds(join.getCluster(), rChild,
rightPushedPredicates, preds.rightInferredPredicates, rChild.getRowType());
RexNode newLeftPredicate = RexUtil.composeConjunction(rB, leftPreds, false);
RexNode newRightPredicate = RexUtil.composeConjunction(rB, rightPreds, 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);
}
RelNode newRel = join.copy(join.getTraitSet(), join.getCondition(),
lChild, rChild, join.getJoinType(), join.isSemiJoinDone());
call.getPlanner().onCopy(join, newRel);
// Register information about pushed predicates
registry.getPushedPredicates(newRel, 0).addAll(leftPushedPredicates);
registry.getPushedPredicates(newRel, 1).addAll(rightPushedPredicates);
call.transformTo(newRel);
}
private ImmutableList<RexNode> getValidPreds(RelOptCluster cluster, RelNode child,
Set<String> predicatesToExclude, List<RexNode> rexs, RelDataType rType) {
InputRefValidator validator = new InputRefValidator(rType.getFieldList());
List<RexNode> valids = new ArrayList<RexNode>(rexs.size());
for (RexNode rex : rexs) {
try {
rex.accept(validator);
valids.add(rex);
} catch (Util.FoundOne e) {
Util.swallow(e, null);
}
}
// We need to filter i) those that have been pushed already as stored in the join,
// and ii) those that were already in the subtree rooted at child
ImmutableList<RexNode> toPush = HiveCalciteUtil.getPredsNotPushedAlready(predicatesToExclude,
child, valids);
return toPush;
}
private RexNode getTypeSafePred(RelOptCluster cluster, RexNode rex, RelDataType rType) {
RexNode typeSafeRex = rex;
if ((typeSafeRex instanceof RexCall) && HiveCalciteUtil.isComparisonOp((RexCall) typeSafeRex)) {
RexBuilder rb = cluster.getRexBuilder();
List<RexNode> fixedPredElems = new ArrayList<RexNode>();
RelDataType commonType = cluster.getTypeFactory().leastRestrictive(
RexUtil.types(((RexCall) rex).getOperands()));
for (RexNode rn : ((RexCall) rex).getOperands()) {
fixedPredElems.add(rb.ensureType(commonType, rn, true));
}
typeSafeRex = rb.makeCall(((RexCall) typeSafeRex).getOperator(), fixedPredElems);
}
return typeSafeRex;
}
private static class InputRefValidator extends RexVisitorImpl<Void> {
private final List<RelDataTypeField> types;
protected InputRefValidator(List<RelDataTypeField> types) {
super(true);
this.types = types;
}
@Override
public Void visitCall(RexCall call) {
if(AnnotationUtils.getAnnotation(GenericUDFOPNotNull.class, Description.class).name().equals(call.getOperator().getName())) {
if(call.getOperands().get(0) instanceof RexInputRef &&
!types.get(((RexInputRef)call.getOperands().get(0)).getIndex()).getType().isNullable()) {
// No need to add not null filter for a constant.
throw new Util.FoundOne(call);
}
}
return super.visitCall(call);
}
}
}