content: /*
   * 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.test;
  
  import org.apache.calcite.plan.hep.HepPlanner;
  import org.apache.calcite.plan.hep.HepProgram;
  import org.apache.calcite.plan.hep.HepProgramBuilder;
  import org.apache.calcite.rel.RelNode;
  import org.apache.calcite.rel.rules.CoreRules;
  import org.apache.calcite.tools.RelBuilder;
  
  import org.junit.jupiter.api.Test;
  
  /**
   * Test cases for {@link org.apache.calcite.rel.metadata.RelMdSelectivity}.
   */
  class RelMdSelectivityTest {
  
    /** Test case for
     * <a href="https://issues.apache.org/jira/browse/CALCITE-4414">[CALCITE-4414]
     * RelMdSelectivity#getSelectivity for Calc can propagate a predicate with wrong reference</a>. */
    @Test void testCalcSelectivityWithPredicate() {
      final RelBuilder builder = RelBuilder.create(RelBuilderTest.config().build());
      final RelNode relNode = builder
          .scan("EMP")
          .project(
              builder.field("DEPTNO"))
          .scan("EMP")
          .project(
              builder.field("DEPTNO"))
          .union(true)
          .projectPlus(builder.field("DEPTNO"))
          .filter(
              builder.equals(
                  builder.field(0),
                  builder.literal(0)))
          .build();
  
      // Program to convert Project + Filter into a single Calc
      final HepProgram program = new HepProgramBuilder()
          .addRuleInstance(CoreRules.FILTER_TO_CALC)
          .addRuleInstance(CoreRules.PROJECT_TO_CALC)
          .addRuleInstance(CoreRules.CALC_MERGE)
          .build();
      final HepPlanner hepPlanner = new HepPlanner(program);
      hepPlanner.setRoot(relNode);
      RelNode output = hepPlanner.findBestExp();
  
      // Add filter on the extra field generated by projectPlus (now a Calc after hepPlanner)
      output = builder
          .push(output)
          .filter(
              builder.equals(
                  builder.field(1),
                  builder.literal(0)))
          .build();
  
      // Should not fail
      output.estimateRowCount(output.getCluster().getMetadataQuery());
    }
  }
  