exec/java-exec/src/main/java/org/apache/drill/exec/planner/cost/DrillRelMdPredicates.java

/*
 * 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.drill.exec.planner.cost;

import org.apache.calcite.plan.RelOptPredicateList;
import org.apache.calcite.plan.RelOptUtil;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.core.Filter;
import org.apache.calcite.rel.metadata.BuiltInMetadata;
import org.apache.calcite.rel.metadata.ReflectiveRelMetadataProvider;
import org.apache.calcite.rel.metadata.RelMdPredicates;
import org.apache.calcite.rel.metadata.RelMetadataProvider;
import org.apache.calcite.rel.metadata.RelMetadataQuery;
import org.apache.calcite.rex.RexBuilder;
import org.apache.calcite.rex.RexUtil;
import org.apache.calcite.util.Util;

public class DrillRelMdPredicates extends RelMdPredicates {

  public static final RelMetadataProvider SOURCE = ReflectiveRelMetadataProvider
    .reflectiveSource(new DrillRelMdPredicates(), BuiltInMetadata.Predicates.Handler.class);

  /**
   * Add the Filter condition to the pulledPredicates list from the input.
   */
  public RelOptPredicateList getPredicates(Filter filter, RelMetadataQuery mq) {
    final RelNode input = filter.getInput();
    final RexBuilder rexBuilder = filter.getCluster().getRexBuilder();
    final RelOptPredicateList inputInfo = mq.getPulledUpPredicates(input);

    return Util.first(inputInfo, RelOptPredicateList.EMPTY)
      .union(rexBuilder,
        RelOptPredicateList.of(rexBuilder,
          RexUtil.retainDeterministic(
            RelOptUtil.conjunctions(RexUtil.expandSearch(rexBuilder, null, filter.getCondition())))));
  }
}