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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.
*/
package org.apache.drill.exec.planner.physical;
import java.util.logging.Logger;
import org.apache.drill.exec.planner.logical.DrillAggregateRel;
import org.apache.drill.exec.planner.logical.RelOptHelper;
import org.apache.drill.exec.planner.physical.AggPrelBase.OperatorPhase;
import org.eigenbase.rel.InvalidRelException;
import org.eigenbase.rel.RelNode;
import org.eigenbase.relopt.RelOptRule;
import org.eigenbase.relopt.RelOptRuleCall;
import org.eigenbase.relopt.RelTrait;
import org.eigenbase.relopt.RelTraitSet;
import org.eigenbase.trace.EigenbaseTrace;
import com.google.common.collect.ImmutableList;
public class HashAggPrule extends AggPruleBase {
public static final RelOptRule INSTANCE = new HashAggPrule();
protected static final Logger tracer = EigenbaseTrace.getPlannerTracer();
private HashAggPrule() {
super(RelOptHelper.some(DrillAggregateRel.class, RelOptHelper.any(RelNode.class)), "HashAggPrule");
}
@Override
public boolean matches(RelOptRuleCall call) {
return PrelUtil.getPlannerSettings(call.getPlanner()).isHashAggEnabled();
}
@Override
public void onMatch(RelOptRuleCall call) {
final DrillAggregateRel aggregate = (DrillAggregateRel) call.rel(0);
final RelNode input = call.rel(1);
if (aggregate.containsDistinctCall() || aggregate.getGroupCount() == 0) {
// currently, don't use HashAggregate if any of the logical aggrs contains DISTINCT or
// if there are no grouping keys
return;
}
RelTraitSet traits = null;
try {
if (aggregate.getGroupSet().isEmpty()) {
DrillDistributionTrait singleDist = DrillDistributionTrait.SINGLETON;
traits = call.getPlanner().emptyTraitSet().plus(Prel.DRILL_PHYSICAL).plus(singleDist);
createTransformRequest(call, aggregate, input, traits);
} else {
// hash distribute on all grouping keys
DrillDistributionTrait distOnAllKeys =
new DrillDistributionTrait(DrillDistributionTrait.DistributionType.HASH_DISTRIBUTED,
ImmutableList.copyOf(getDistributionField(aggregate, true /* get all grouping keys */)));
traits = call.getPlanner().emptyTraitSet().plus(Prel.DRILL_PHYSICAL).plus(distOnAllKeys);
createTransformRequest(call, aggregate, input, traits);
// hash distribute on single grouping key
DrillDistributionTrait distOnOneKey =
new DrillDistributionTrait(DrillDistributionTrait.DistributionType.HASH_DISTRIBUTED,
ImmutableList.copyOf(getDistributionField(aggregate, false /* get single grouping key */)));
traits = call.getPlanner().emptyTraitSet().plus(Prel.DRILL_PHYSICAL).plus(distOnOneKey);
createTransformRequest(call, aggregate, input, traits);
if (create2PhasePlan(call, aggregate)) {
traits = call.getPlanner().emptyTraitSet().plus(Prel.DRILL_PHYSICAL) ;
RelNode convertedInput = convert(input, traits);
new TwoPhaseSubset(call, distOnAllKeys).go(aggregate, convertedInput);
}
}
} catch (InvalidRelException e) {
tracer.warning(e.toString());
}
}
private class TwoPhaseSubset extends SubsetTransformer<DrillAggregateRel, InvalidRelException> {
final RelTrait distOnAllKeys;
public TwoPhaseSubset(RelOptRuleCall call, RelTrait distOnAllKeys) {
super(call);
this.distOnAllKeys = distOnAllKeys;
}
@Override
public RelNode convertChild(DrillAggregateRel aggregate, RelNode input) throws InvalidRelException {
RelTraitSet traits = newTraitSet(Prel.DRILL_PHYSICAL, input.getTraitSet().getTrait(DrillDistributionTraitDef.INSTANCE));
RelNode newInput = convert(input, traits);
HashAggPrel phase1Agg = new HashAggPrel(aggregate.getCluster(), traits, newInput,
aggregate.getGroupSet(),
aggregate.getAggCallList(),
OperatorPhase.PHASE_1of2);
HashToRandomExchangePrel exch =
new HashToRandomExchangePrel(phase1Agg.getCluster(), phase1Agg.getTraitSet().plus(Prel.DRILL_PHYSICAL).plus(distOnAllKeys),
phase1Agg, ImmutableList.copyOf(getDistributionField(aggregate, true)));
HashAggPrel phase2Agg = new HashAggPrel(aggregate.getCluster(), exch.getTraitSet(), exch,
aggregate.getGroupSet(),
phase1Agg.getPhase2AggCalls(),
OperatorPhase.PHASE_2of2);
return phase2Agg;
}
}
private void createTransformRequest(RelOptRuleCall call, DrillAggregateRel aggregate,
RelNode input, RelTraitSet traits) throws InvalidRelException {
final RelNode convertedInput = convert(input, PrelUtil.fixTraits(call, traits));
HashAggPrel newAgg = new HashAggPrel(aggregate.getCluster(), traits, convertedInput, aggregate.getGroupSet(),
aggregate.getAggCallList(), OperatorPhase.PHASE_1of1);
call.transformTo(newAgg);
}
}