| /* |
| * 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 org.apache.calcite.plan.RelOptRuleCall; |
| import org.apache.calcite.plan.RelTraitSet; |
| import org.apache.calcite.rel.RelNode; |
| import org.apache.drill.exec.planner.logical.DrillRel; |
| import org.apache.drill.exec.planner.logical.MetadataControllerRel; |
| import org.apache.drill.exec.planner.logical.RelOptHelper; |
| |
| public class MetadataControllerPrule extends Prule { |
| public static final MetadataControllerPrule INSTANCE = new MetadataControllerPrule(); |
| |
| private MetadataControllerPrule() { |
| super(RelOptHelper.some(MetadataControllerRel.class, DrillRel.DRILL_LOGICAL, |
| RelOptHelper.any(RelNode.class)), "MetadataControllerPrule"); |
| } |
| |
| @Override |
| public void onMatch(RelOptRuleCall call) { |
| MetadataControllerRel relNode = call.rel(0); |
| RelNode left = relNode.getLeft(); |
| RelNode right = relNode.getRight(); |
| RelTraitSet traits = call.getPlanner().emptyTraitSet().plus(Prel.DRILL_PHYSICAL).plus(DrillDistributionTrait.SINGLETON); |
| RelNode convertedLeft = convert(left, traits); |
| RelNode convertedRight = convert(right, traits); |
| call.transformTo(new MetadataControllerPrel(relNode.getCluster(), |
| // force singleton execution since this is the final step for metadata collection which collects all results into one |
| relNode.getTraitSet().plus(Prel.DRILL_PHYSICAL).plus(DrillDistributionTrait.SINGLETON), |
| convertedLeft, convertedRight, relNode.getContext())); |
| } |
| } |