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This module bridges Table/SQL API and runtime. It contains
all resources that are required during pre-flight and runtime
phase. The content of this module is work-in-progress. It will
replace flink-table-planner once it is stable. See FLINK-11439
and FLIP-32 for more details.
/*
* 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.flink.table.planner.plan.rules.logical;
import org.apache.calcite.plan.RelOptRule;
import org.apache.calcite.plan.RelOptRuleCall;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.core.Join;
import org.apache.calcite.rel.core.Project;
import org.apache.calcite.rel.core.RelFactories;
import org.apache.calcite.rel.rules.PushProjector;
import org.apache.calcite.rel.type.RelDataTypeField;
import org.apache.calcite.rex.RexNode;
import org.apache.calcite.tools.RelBuilderFactory;
import java.util.ArrayList;
import java.util.List;
/**
* This rule is copied from Calcite's {@link org.apache.calcite.rel.rules.ProjectJoinTransposeRule}.
* Modification: - Does not match SEMI/ANTI join now
*/
/**
* Planner rule that pushes a {@link org.apache.calcite.rel.core.Project} past a {@link
* org.apache.calcite.rel.core.Join} by splitting the projection into a projection on top of each
* child of the join.
*/
public class FlinkProjectJoinTransposeRule extends RelOptRule {
public static final FlinkProjectJoinTransposeRule INSTANCE =
new FlinkProjectJoinTransposeRule(expr -> true, RelFactories.LOGICAL_BUILDER);
// ~ Instance fields --------------------------------------------------------
/** Condition for expressions that should be preserved in the projection. */
private final PushProjector.ExprCondition preserveExprCondition;
// ~ Constructors -----------------------------------------------------------
/**
* Creates a ProjectJoinTransposeRule with an explicit condition.
*
* @param preserveExprCondition Condition for expressions that should be preserved in the
* projection
*/
public FlinkProjectJoinTransposeRule(
PushProjector.ExprCondition preserveExprCondition, RelBuilderFactory relFactory) {
super(operand(Project.class, operand(Join.class, any())), relFactory, null);
this.preserveExprCondition = preserveExprCondition;
}
// ~ Methods ----------------------------------------------------------------
// implement RelOptRule
public void onMatch(RelOptRuleCall call) {
Project origProj = call.rel(0);
final Join join = call.rel(1);
if (!join.getJoinType().projectsRight()) {
return; // TODO: support SEMI/ANTI join later
}
// locate all fields referenced in the projection and join condition;
// determine which inputs are referenced in the projection and
// join condition; if all fields are being referenced and there are no
// special expressions, no point in proceeding any further
PushProjector pushProject =
new PushProjector(
origProj, join.getCondition(), join, preserveExprCondition, call.builder());
if (pushProject.locateAllRefs()) {
return;
}
// create left and right projections, projecting only those
// fields referenced on each side
RelNode leftProjRel = pushProject.createProjectRefsAndExprs(join.getLeft(), true, false);
RelNode rightProjRel = pushProject.createProjectRefsAndExprs(join.getRight(), true, true);
// convert the join condition to reference the projected columns
RexNode newJoinFilter = null;
int[] adjustments = pushProject.getAdjustments();
if (join.getCondition() != null) {
List projJoinFieldList = new ArrayList<>();
projJoinFieldList.addAll(join.getSystemFieldList());
projJoinFieldList.addAll(leftProjRel.getRowType().getFieldList());
projJoinFieldList.addAll(rightProjRel.getRowType().getFieldList());
newJoinFilter =
pushProject.convertRefsAndExprs(
join.getCondition(), projJoinFieldList, adjustments);
}
// create a new join with the projected children
Join newJoinRel =
join.copy(
join.getTraitSet(),
newJoinFilter,
leftProjRel,
rightProjRel,
join.getJoinType(),
join.isSemiJoinDone());
// put the original project on top of the join, converting it to
// reference the modified projection list
RelNode topProject = pushProject.createNewProject(newJoinRel, adjustments);
call.transformTo(topProject);
}
}
// End FlinkProjectJoinTransposeRule.java