| /* |
| * 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.calcite.rel.rules; |
| |
| import org.apache.calcite.plan.RelOptRuleCall; |
| import org.apache.calcite.plan.RelOptUtil; |
| import org.apache.calcite.plan.RelRule; |
| import org.apache.calcite.rel.core.Project; |
| import org.apache.calcite.rel.logical.LogicalProject; |
| import org.apache.calcite.tools.RelBuilder; |
| import org.apache.calcite.tools.RelBuilderFactory; |
| |
| import org.immutables.value.Value; |
| |
| /** |
| * Planner rule that pushes |
| * {@link org.apache.calcite.rel.core.Project} |
| * into a {@link MultiJoin}, |
| * creating a richer {@code MultiJoin}. |
| * |
| * @see org.apache.calcite.rel.rules.FilterMultiJoinMergeRule |
| * @see CoreRules#PROJECT_MULTI_JOIN_MERGE |
| */ |
| @Value.Enclosing |
| public class ProjectMultiJoinMergeRule |
| extends RelRule<ProjectMultiJoinMergeRule.Config> |
| implements TransformationRule { |
| |
| /** Creates a ProjectMultiJoinMergeRule. */ |
| protected ProjectMultiJoinMergeRule(Config config) { |
| super(config); |
| } |
| |
| @Deprecated // to be removed before 2.0 |
| public ProjectMultiJoinMergeRule(RelBuilderFactory relBuilderFactory) { |
| this(Config.DEFAULT.withRelBuilderFactory(relBuilderFactory) |
| .as(Config.class)); |
| } |
| |
| @Deprecated // to be removed before 2.0 |
| public ProjectMultiJoinMergeRule(Class<? extends Project> projectClass, |
| RelBuilderFactory relBuilderFactory) { |
| this(Config.DEFAULT.withRelBuilderFactory(relBuilderFactory) |
| .as(Config.class) |
| .withOperandFor(projectClass, MultiJoin.class)); |
| } |
| |
| //~ Methods ---------------------------------------------------------------- |
| |
| @Override public void onMatch(RelOptRuleCall call) { |
| Project project = call.rel(0); |
| MultiJoin multiJoin = call.rel(1); |
| |
| // if all inputs have their projFields set, then projection information |
| // has already been pushed into each input |
| boolean allSet = true; |
| for (int i = 0; i < multiJoin.getInputs().size(); i++) { |
| if (multiJoin.getProjFields().get(i) == null) { |
| allSet = false; |
| break; |
| } |
| } |
| if (allSet) { |
| return; |
| } |
| |
| // create a new MultiJoin that reflects the columns in the projection |
| // above the MultiJoin |
| final RelBuilder relBuilder = call.builder(); |
| MultiJoin newMultiJoin = |
| RelOptUtil.projectMultiJoin(multiJoin, project); |
| relBuilder.push(newMultiJoin) |
| .project(project.getProjects(), project.getRowType().getFieldNames()); |
| |
| call.transformTo(relBuilder.build()); |
| } |
| |
| /** Rule configuration. */ |
| @Value.Immutable |
| public interface Config extends RelRule.Config { |
| Config DEFAULT = ImmutableProjectMultiJoinMergeRule.Config.of() |
| .withOperandFor(LogicalProject.class, MultiJoin.class); |
| |
| @Override default ProjectMultiJoinMergeRule toRule() { |
| return new ProjectMultiJoinMergeRule(this); |
| } |
| |
| /** Defines an operand tree for the given classes. */ |
| default Config withOperandFor(Class<? extends Project> projectClass, |
| Class<MultiJoin> multiJoinClass) { |
| return withOperandSupplier(b0 -> |
| b0.operand(projectClass).oneInput(b1 -> |
| b1.operand(multiJoinClass).anyInputs())) |
| .as(Config.class); |
| } |
| } |
| } |