/**
* 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.logical;
import java.util.logging.Logger;
import org.eigenbase.rel.AggregateRel;
import org.eigenbase.rel.InvalidRelException;
import org.eigenbase.rel.RelNode;
import org.eigenbase.relopt.Convention;
import org.eigenbase.relopt.RelOptRule;
import org.eigenbase.relopt.RelOptRuleCall;
import org.eigenbase.relopt.RelTraitSet;
import org.eigenbase.trace.EigenbaseTrace;
/**
* Rule that converts an {@link AggregateRel} to a {@link DrillAggregateRel}, implemented by a Drill "segment" operation
* followed by a "collapseaggregate" operation.
*/
public class DrillAggregateRule extends RelOptRule {
public static final RelOptRule INSTANCE = new DrillAggregateRule();
protected static final Logger tracer = EigenbaseTrace.getPlannerTracer();
private DrillAggregateRule() {
super(RelOptHelper.some(AggregateRel.class, Convention.NONE, RelOptHelper.any(RelNode.class)), "DrillAggregateRule");
}
@Override
public void onMatch(RelOptRuleCall call) {
final AggregateRel aggregate = (AggregateRel) call.rel(0);
final RelNode input = call.rel(1);
if (aggregate.containsDistinctCall()) {
// currently, don't use this rule if any of the aggregates contains DISTINCT
return;
}
final RelTraitSet traits = aggregate.getTraitSet().plus(DrillRel.DRILL_LOGICAL);
final RelNode convertedInput = convert(input, input.getTraitSet().plus(DrillRel.DRILL_LOGICAL));
try {
call.transformTo(new DrillAggregateRel(aggregate.getCluster(), traits, convertedInput, aggregate.getGroupSet(),
aggregate.getAggCallList()));
} catch (InvalidRelException e) {
tracer.warning(e.toString());
}
}
}