/**
* 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.common;
import org.apache.drill.exec.planner.cost.DrillCostBase;
import org.apache.drill.exec.planner.cost.DrillCostBase.DrillCostFactory;
import org.apache.drill.exec.planner.physical.PrelUtil;
import org.eigenbase.rel.RelNode;
import org.eigenbase.rel.RelWriter;
import org.eigenbase.rel.SingleRel;
import org.eigenbase.relopt.RelOptCluster;
import org.eigenbase.relopt.RelOptCost;
import org.eigenbase.relopt.RelOptPlanner;
import org.eigenbase.relopt.RelTraitSet;
import org.eigenbase.rex.RexLiteral;
import org.eigenbase.rex.RexNode;
/**
* Base class for logical and physical Limits implemented in Drill
*/
public abstract class DrillLimitRelBase extends SingleRel implements DrillRelNode {
protected RexNode offset;
protected RexNode fetch;
public DrillLimitRelBase(RelOptCluster cluster, RelTraitSet traitSet, RelNode child, RexNode offset, RexNode fetch) {
super(cluster, traitSet, child);
this.offset = offset;
this.fetch = fetch;
}
public RexNode getOffset() {
return this.offset;
}
public RexNode getFetch() {
return this.fetch;
}
@Override
public RelOptCost computeSelfCost(RelOptPlanner planner) {
if(PrelUtil.getSettings(getCluster()).useDefaultCosting()) {
return super.computeSelfCost(planner).multiplyBy(.1);
}
int off = offset != null ? RexLiteral.intValue(offset) : 0 ;
int f = fetch != null ? RexLiteral.intValue(fetch) : 0 ;
double numRows = off + f;
double cpuCost = DrillCostBase.COMPARE_CPU_COST * numRows;
DrillCostFactory costFactory = (DrillCostFactory)planner.getCostFactory();
return costFactory.makeCost(numRows, cpuCost, 0, 0);
}
@Override
public RelWriter explainTerms(RelWriter pw) {
super.explainTerms(pw);
pw.itemIf("offset", offset, offset != null);
pw.itemIf("fetch", fetch, fetch != null);
return pw;
}
}