exec/java-exec/src/main/java/org/apache/drill/exec/planner/physical/ValuesPrule.java

/*
 * 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
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 */
package org.apache.drill.exec.planner.physical;

import org.apache.calcite.plan.RelOptRuleCall;
import org.apache.drill.exec.planner.logical.DrillRel;
import org.apache.drill.exec.planner.logical.DrillValuesRel;
import org.apache.drill.exec.planner.logical.RelOptHelper;

public class ValuesPrule extends Prule {

  public static final ValuesPrule INSTANCE = new ValuesPrule();

  private ValuesPrule() {
    super(RelOptHelper.any(DrillValuesRel.class, DrillRel.DRILL_LOGICAL), "Prel.ValuesPrule");
  }

  @Override
  public void onMatch(final RelOptRuleCall call) {
    DrillValuesRel rel = call.rel(0);
    call.transformTo(new ValuesPrel(rel.getCluster(), rel.getRowType(), rel.getTuples(),
      // force singleton execution since values rel contains all results and they cannot be split
      rel.getTraitSet().plus(Prel.DRILL_PHYSICAL).plus(DrillDistributionTrait.SINGLETON),
      rel.getContent()));
  }
}