| /** |
| * 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.logical; |
| |
| import com.google.common.collect.ImmutableList; |
| import org.apache.calcite.plan.RelOptRule; |
| import org.apache.calcite.plan.RelOptRuleCall; |
| import org.apache.calcite.plan.RelOptRuleOperand; |
| import org.apache.calcite.rel.RelNode; |
| import org.apache.calcite.util.Pair; |
| import org.apache.drill.exec.physical.base.GroupScan; |
| import org.apache.drill.exec.planner.logical.partition.PruneScanRule; |
| import org.apache.drill.exec.store.parquet.ParquetGroupScan; |
| |
| import java.io.IOException; |
| import java.util.concurrent.TimeUnit; |
| |
| public abstract class DrillPushLimitToScanRule extends RelOptRule { |
| static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(DrillPushLimitToScanRule.class); |
| |
| private DrillPushLimitToScanRule(RelOptRuleOperand operand, String description) { |
| super(operand, description); |
| } |
| |
| public static DrillPushLimitToScanRule LIMIT_ON_SCAN = new DrillPushLimitToScanRule( |
| RelOptHelper.some(DrillLimitRel.class, RelOptHelper.any(DrillScanRel.class)), "DrillPushLimitToScanRule_LimitOnScan") { |
| @Override |
| public boolean matches(RelOptRuleCall call) { |
| DrillLimitRel limitRel = call.rel(0); |
| DrillScanRel scanRel = call.rel(1); |
| // For now only applies to Parquet. And pushdown only apply limit but not offset, |
| // so if getFetch() return null no need to run this rule. |
| if (scanRel.getGroupScan().supportsLimitPushdown() && (limitRel.getFetch() != null)) { |
| return true; |
| } |
| return false; |
| } |
| |
| @Override |
| public void onMatch(RelOptRuleCall call) { |
| DrillLimitRel limitRel = call.rel(0); |
| DrillScanRel scanRel = call.rel(1); |
| doOnMatch(call, limitRel, scanRel, null); |
| } |
| }; |
| |
| public static DrillPushLimitToScanRule LIMIT_ON_PROJECT = new DrillPushLimitToScanRule( |
| RelOptHelper.some(DrillLimitRel.class, RelOptHelper.some(DrillProjectRel.class, RelOptHelper.any(DrillScanRel.class))), "DrillPushLimitToScanRule_LimitOnProject") { |
| @Override |
| public boolean matches(RelOptRuleCall call) { |
| DrillLimitRel limitRel = call.rel(0); |
| DrillScanRel scanRel = call.rel(2); |
| // For now only applies to Parquet. And pushdown only apply limit but not offset, |
| // so if getFetch() return null no need to run this rule. |
| if (scanRel.getGroupScan().supportsLimitPushdown() && (limitRel.getFetch() != null)) { |
| return true; |
| } |
| return false; |
| } |
| |
| @Override |
| public void onMatch(RelOptRuleCall call) { |
| DrillLimitRel limitRel = call.rel(0); |
| DrillProjectRel projectRel = call.rel(1); |
| DrillScanRel scanRel = call.rel(2); |
| doOnMatch(call, limitRel, scanRel, projectRel); |
| } |
| }; |
| |
| |
| protected void doOnMatch(RelOptRuleCall call, DrillLimitRel limitRel, DrillScanRel scanRel, DrillProjectRel projectRel){ |
| try { |
| final int rowCountRequested = (int) limitRel.getRows(); |
| |
| final GroupScan newGroupScan = scanRel.getGroupScan().applyLimit(rowCountRequested); |
| |
| if (newGroupScan == null ) { |
| return; |
| } |
| |
| DrillScanRel newScanRel = new DrillScanRel(scanRel.getCluster(), |
| scanRel.getTraitSet(), |
| scanRel.getTable(), |
| newGroupScan, |
| scanRel.getRowType(), |
| scanRel.getColumns(), |
| scanRel.partitionFilterPushdown()); |
| |
| final RelNode newLimit; |
| if (projectRel != null) { |
| final RelNode newProject = projectRel.copy(projectRel.getTraitSet(), ImmutableList.of((RelNode)newScanRel)); |
| newLimit = limitRel.copy(limitRel.getTraitSet(), ImmutableList.of((RelNode)newProject)); |
| } else { |
| newLimit = limitRel.copy(limitRel.getTraitSet(), ImmutableList.of((RelNode)newScanRel)); |
| } |
| |
| call.transformTo(newLimit); |
| logger.debug("Converted to a new DrillScanRel" + newScanRel.getGroupScan()); |
| } catch (Exception e) { |
| logger.warn("Exception while using the pruned partitions.", e); |
| } |
| |
| } |
| } |