/*
 * 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.iotdb.db.queryengine.plan.planner;

import org.apache.iotdb.db.queryengine.plan.planner.plan.FragmentInstance;

import java.util.List;

/**
 * The interface is used to transform one PlanFragment into one or more FragmentInstances which
 * could run in parallel
 */
public interface IFragmentParallelPlaner {
  /**
   * The relation between each PlanFragment is necessary because sometimes we need to change the
   * source/sink for each FragmentInstance according to its upstream/downstream
   *
   * @return All the FragmentInstances which can run in parallel
   */
  List<FragmentInstance> parallelPlan();
}
