/**
* 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.List;
import java.util.logging.Logger;
import org.apache.drill.exec.planner.logical.DrillUnionRel;
import org.apache.drill.exec.planner.logical.RelOptHelper;
import org.eigenbase.rel.InvalidRelException;
import org.eigenbase.rel.RelNode;
import org.eigenbase.relopt.RelOptRule;
import org.eigenbase.relopt.RelOptRuleCall;
import org.eigenbase.relopt.RelTraitSet;
import org.eigenbase.trace.EigenbaseTrace;
import com.google.common.collect.Lists;
public class UnionDistinctPrule extends Prule {
public static final RelOptRule INSTANCE = new UnionDistinctPrule();
protected static final Logger tracer = EigenbaseTrace.getPlannerTracer();
private UnionDistinctPrule() {
super(
RelOptHelper.any(DrillUnionRel.class), "Prel.UnionDistinctPrule");
}
@Override
public boolean matches(RelOptRuleCall call) {
DrillUnionRel union = (DrillUnionRel) call.rel(0);
return (union.isDistinct() && union.isHomogeneous(false /* don't compare names */));
}
@Override
public void onMatch(RelOptRuleCall call) {
final DrillUnionRel union = (DrillUnionRel) call.rel(0);
final List<RelNode> inputs = union.getInputs();
List<RelNode> convertedInputList = Lists.newArrayList();
RelTraitSet traits = call.getPlanner().emptyTraitSet().plus(Prel.DRILL_PHYSICAL);
try {
for (int i = 0; i < inputs.size(); i++) {
RelNode convertedInput = convert(inputs.get(i), PrelUtil.fixTraits(call, traits));
convertedInputList.add(convertedInput);
}
traits = call.getPlanner().emptyTraitSet().plus(Prel.DRILL_PHYSICAL).plus(DrillDistributionTrait.SINGLETON);
UnionDistinctPrel unionDistinct = new UnionDistinctPrel(union.getCluster(), traits, convertedInputList);
call.transformTo(unionDistinct);
} catch (InvalidRelException e) {
tracer.warning(e.toString());
}
}
}