com.hazelcast.org.apache.calcite.rel.rules.FilterCalcMergeRule Maven / Gradle / Ivy
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* 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,
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package com.hazelcast.org.apache.calcite.rel.rules;
import com.hazelcast.org.apache.calcite.plan.RelOptRule;
import com.hazelcast.org.apache.calcite.plan.RelOptRuleCall;
import com.hazelcast.org.apache.calcite.rel.core.Filter;
import com.hazelcast.org.apache.calcite.rel.core.RelFactories;
import com.hazelcast.org.apache.calcite.rel.logical.LogicalCalc;
import com.hazelcast.org.apache.calcite.rel.logical.LogicalFilter;
import com.hazelcast.org.apache.calcite.rex.RexBuilder;
import com.hazelcast.org.apache.calcite.rex.RexProgram;
import com.hazelcast.org.apache.calcite.rex.RexProgramBuilder;
import com.hazelcast.org.apache.calcite.tools.RelBuilderFactory;
/**
* Planner rule that merges a
* {@link com.hazelcast.org.apache.calcite.rel.logical.LogicalFilter} and a
* {@link com.hazelcast.org.apache.calcite.rel.logical.LogicalCalc}. The
* result is a {@link com.hazelcast.org.apache.calcite.rel.logical.LogicalCalc}
* whose filter condition is the logical AND of the two.
*
* @see FilterMergeRule
*/
public class FilterCalcMergeRule extends RelOptRule implements TransformationRule {
//~ Static fields/initializers ---------------------------------------------
public static final FilterCalcMergeRule INSTANCE =
new FilterCalcMergeRule(RelFactories.LOGICAL_BUILDER);
//~ Constructors -----------------------------------------------------------
/**
* Creates a FilterCalcMergeRule.
*
* @param relBuilderFactory Builder for relational expressions
*/
public FilterCalcMergeRule(RelBuilderFactory relBuilderFactory) {
super(
operand(
Filter.class,
operand(LogicalCalc.class, any())),
relBuilderFactory, null);
}
//~ Methods ----------------------------------------------------------------
public void onMatch(RelOptRuleCall call) {
final LogicalFilter filter = call.rel(0);
final LogicalCalc calc = call.rel(1);
// Don't merge a filter onto a calc which contains windowed aggregates.
// That would effectively be pushing a multiset down through a filter.
// We'll have chance to merge later, when the over is expanded.
if (calc.getProgram().containsAggs()) {
return;
}
// Create a program containing the filter.
final RexBuilder rexBuilder = filter.getCluster().getRexBuilder();
final RexProgramBuilder progBuilder =
new RexProgramBuilder(
calc.getRowType(),
rexBuilder);
progBuilder.addIdentity();
progBuilder.addCondition(filter.getCondition());
RexProgram topProgram = progBuilder.getProgram();
RexProgram bottomProgram = calc.getProgram();
// Merge the programs together.
RexProgram mergedProgram =
RexProgramBuilder.mergePrograms(
topProgram,
bottomProgram,
rexBuilder);
final LogicalCalc newCalc =
LogicalCalc.create(calc.getInput(), mergedProgram);
call.transformTo(newCalc);
}
}