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;
  
  import com.google.common.collect.ImmutableList;
  
  import org.checkerframework.checker.nullness.qual.Nullable;
  
  import java.util.List;
  
  /**
   * Extension to {@link SqlValidatorTable} with extra, optional metadata.
   *
   * <p>Used to flag individual columns as 'must-filter'.
   */
  public interface SemanticTable {
    /** Returns the filter expression for {@code column}
     * if it is a {@link #mustFilter(int) must-filter} column,
     * or null if it is not a must-filter column.
     *
     * @param column Column ordinal (0-based)
     *
     * @throws IndexOutOfBoundsException if column ordinal is out of range */
    default @Nullable String getFilter(int column) {
      return null;
    }
  
    /** Returns whether {@code column} must be filtered in any query
     * that references this table.
     *
     * @param column Column ordinal (0-based)
     *
     * @throws IndexOutOfBoundsException if column ordinal is out of range */
    default boolean mustFilter(int column) {
      return getFilter(column) != null;
    }
  
    /**
     * Returns a list of column ordinals (0-based) of fields that defuse
     * must-filter columns when filtered on.
     */
    default List<Integer> bypassFieldList() {
      return ImmutableList.of();
    }
  }
  