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.rel.metadata;
  
  /**
   * Mapping from an input column of a {@link org.apache.calcite.rel.RelNode} to
   * one of its output columns.
   */
  public class RelColumnMapping {
    public RelColumnMapping(
        int iOutputColumn, int iInputRel, int iInputColumn, boolean derived) {
      this.iOutputColumn = iOutputColumn;
      this.iInputRel = iInputRel;
      this.iInputColumn = iInputColumn;
      this.derived = derived;
    }
  
    //~ Instance fields --------------------------------------------------------
  
    /**
     * 0-based ordinal of mapped output column.
     */
    public final int iOutputColumn;
  
    /**
     * 0-based ordinal of mapped input rel.
     */
    public final int iInputRel;
  
    /**
     * 0-based ordinal of mapped column within input rel.
     */
    public final int iInputColumn;
  
    /**
     * Whether the column mapping transforms the input.
     */
    public final boolean derived;
  }
  