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.sql.validate;
  
  /** One of the inputs of a {@link SqlValidatorScope}.
   *
   * <p>Most commonly, it is an item in a FROM clause, and consists of a namespace
   * (the columns it provides), and optional name (table alias), and ordinal
   * within the FROM clause. */
  class ScopeChild {
    final int ordinal;
    final String name;
    final SqlValidatorNamespace namespace;
    final boolean nullable;
  
    /** Creates a ScopeChild.
     *
     * @param ordinal Ordinal of child within parent scope
     * @param name Table alias
     * @param namespace Namespace of child
     * @param nullable Whether fields of the child are nullable when seen from the
     *   parent, due to outer joins
     */
    ScopeChild(int ordinal, String name, SqlValidatorNamespace namespace,
        boolean nullable) {
      this.ordinal = ordinal;
      this.name = name;
      this.namespace = namespace;
      this.nullable = nullable;
    }
  
    @Override public String toString() {
      return ordinal + ": " + name + ": " + namespace
          + (nullable ? " (nullable)" : "");
    }
  }
  