/* * 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.RelOptRule; import org.apache.calcite.plan.RelOptRuleCall; import org.apache.calcite.rel.core.Calc; import org.apache.calcite.rel.core.Filter; import org.apache.calcite.rel.core.RelFactories; import org.apache.calcite.rex.RexNode; import org.apache.calcite.tools.RelBuilder; import org.apache.calcite.tools.RelBuilderFactory; import org.apache.calcite.util.Pair; import com.google.common.collect.ImmutableList; /** * Planner rule that converts a {@link Calc} * to a {@link org.apache.calcite.rel.core.Project} * and {@link Filter}. * * <p>Not enabled by default, as it works against the usual flow, which is to * convert {@code Project} and {@code Filter} to {@code Calc}. But useful for * specific tasks, such as optimizing before calling an * {@link org.apache.calcite.interpreter.Interpreter}. */ public class CalcSplitRule extends RelOptRule implements TransformationRule { public static final CalcSplitRule INSTANCE = new CalcSplitRule(RelFactories.LOGICAL_BUILDER); /** * Creates a CalcSplitRule. * * @param relBuilderFactory Builder for relational expressions */ public CalcSplitRule(RelBuilderFactory relBuilderFactory) { super(operand(Calc.class, any()), relBuilderFactory, null); } @Override public void onMatch(RelOptRuleCall call) { final Calc calc = call.rel(0); final Pair<ImmutableList<RexNode>, ImmutableList<RexNode>> projectFilter = calc.getProgram().split(); final RelBuilder relBuilder = call.builder(); relBuilder.push(calc.getInput()); relBuilder.filter(projectFilter.right); relBuilder.project(projectFilter.left, calc.getRowType().getFieldNames()); call.transformTo(relBuilder.build()); } }