/**
* 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 org.apache.drill.common.expression.SchemaPath;
import org.apache.drill.exec.physical.base.GroupScan;
import org.apache.drill.exec.planner.logical.DrillScanRel;
import org.apache.drill.exec.planner.logical.RelOptHelper;
import org.eigenbase.relopt.RelOptRule;
import org.eigenbase.relopt.RelOptRuleCall;
import org.eigenbase.relopt.RelTraitSet;
public class ScanPrule extends Prule{
public static final RelOptRule INSTANCE = new ScanPrule();
public ScanPrule() {
super(RelOptHelper.any(DrillScanRel.class), "Prel.ScanPrule");
}
@Override
public void onMatch(RelOptRuleCall call) {
final DrillScanRel scan = (DrillScanRel) call.rel(0);
GroupScan groupScan = scan.getGroupScan();
DrillDistributionTrait partition = groupScan.getMaxParallelizationWidth() > 1 ? DrillDistributionTrait.RANDOM_DISTRIBUTED : DrillDistributionTrait.SINGLETON;
final RelTraitSet traits = scan.getTraitSet().plus(Prel.DRILL_PHYSICAL).plus(partition);
final DrillScanPrel newScan = ScanPrel.create(scan, traits, groupScan, scan.getRowType());
call.transformTo(newScan);
}
}