| /* |
| * 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.calcite.sql.SqlKind; |
| |
| import org.apache.calcite.util.ImmutableBitSet; |
| import org.apache.drill.exec.planner.logical.DrillAggregateRel; |
| import org.apache.drill.exec.planner.physical.DrillDistributionTrait.DistributionField; |
| import org.apache.calcite.rel.core.AggregateCall; |
| import org.apache.calcite.rel.RelNode; |
| import org.apache.calcite.plan.RelOptRuleCall; |
| import org.apache.calcite.plan.RelOptRuleOperand; |
| |
| import org.apache.drill.shaded.guava.com.google.common.collect.Lists; |
| |
| // abstract base class for the aggregation physical rules |
| public abstract class AggPruleBase extends Prule { |
| |
| protected AggPruleBase(RelOptRuleOperand operand, String description) { |
| super(operand, description); |
| } |
| |
| protected List<DistributionField> getDistributionField(DrillAggregateRel rel, boolean allFields) { |
| List<DistributionField> groupByFields = Lists.newArrayList(); |
| |
| for (int group : remapGroupSet(rel.getGroupSet())) { |
| DistributionField field = new DistributionField(group); |
| groupByFields.add(field); |
| |
| if (!allFields && groupByFields.size() == 1) { |
| // TODO: if we are only interested in 1 grouping field, pick the first one for now.. |
| // but once we have num distinct values (NDV) statistics, we should pick the one |
| // with highest NDV. |
| break; |
| } |
| } |
| |
| return groupByFields; |
| } |
| |
| // Create 2 phase aggr plan for aggregates such as SUM, MIN, MAX |
| // If any of the aggregate functions are not one of these, then we |
| // currently won't generate a 2 phase plan. |
| protected boolean create2PhasePlan(RelOptRuleCall call, DrillAggregateRel aggregate) { |
| PlannerSettings settings = PrelUtil.getPlannerSettings(call.getPlanner()); |
| RelNode child = call.rel(0).getInputs().get(0); |
| boolean smallInput = |
| child.estimateRowCount(child.getCluster().getMetadataQuery()) < settings.getSliceTarget(); |
| if (!settings.isMultiPhaseAggEnabled() || settings.isSingleMode() |
| // Can override a small child - e.g., for testing with a small table |
| || (smallInput && !settings.isForce2phaseAggr())) { |
| return false; |
| } |
| |
| for (AggregateCall aggCall : aggregate.getAggCallList()) { |
| String name = aggCall.getAggregation().getName(); |
| if (!(name.equals(SqlKind.SUM.name()) |
| || name.equals(SqlKind.MIN.name()) |
| || name.equals(SqlKind.MAX.name()) |
| || name.equals(SqlKind.COUNT.name()) |
| || name.equals("$SUM0"))) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Returns group-by keys with the remapped arguments for specified aggregate. |
| * |
| * @param groupSet ImmutableBitSet of aggregate rel node, whose group-by keys should be remapped. |
| * @return {@link ImmutableBitSet} instance with remapped keys. |
| */ |
| public static ImmutableBitSet remapGroupSet(ImmutableBitSet groupSet) { |
| List<Integer> newGroupSet = Lists.newArrayList(); |
| int groupSetToAdd = 0; |
| for (int ignored : groupSet) { |
| newGroupSet.add(groupSetToAdd++); |
| } |
| return ImmutableBitSet.of(newGroupSet); |
| } |
| } |