| /** |
| * 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. |
| **/ |
| |
| #ifndef QUICKSTEP_QUERY_OPTIMIZER_RULES_ELIMINATE_EMPTY_NODE_HPP_ |
| #define QUICKSTEP_QUERY_OPTIMIZER_RULES_ELIMINATE_EMPTY_NODE_HPP_ |
| |
| #include <string> |
| |
| #include "query_optimizer/physical/Physical.hpp" |
| #include "query_optimizer/rules/Rule.hpp" |
| #include "utility/Macros.hpp" |
| |
| namespace quickstep { |
| |
| class CatalogDatabase; |
| |
| namespace optimizer { |
| |
| /** \addtogroup OptimizerRules |
| * @{ |
| */ |
| |
| /** |
| * @brief Rule that applies to a physical plan to eliminate a node with an empty |
| * TableReference to a Selection on a temp table. |
| */ |
| class EliminateEmptyNode : public Rule<physical::Physical> { |
| public: |
| /** |
| * @brief Constructor. |
| */ |
| explicit EliminateEmptyNode(CatalogDatabase *catalog_database) |
| : catalog_database_(catalog_database) {} |
| |
| ~EliminateEmptyNode() override {} |
| |
| std::string getName() const override { |
| return "EliminateEmptyNode"; |
| } |
| |
| physical::PhysicalPtr apply(const physical::PhysicalPtr &input) override; |
| |
| private: |
| CatalogDatabase *catalog_database_; |
| |
| DISALLOW_COPY_AND_ASSIGN(EliminateEmptyNode); |
| }; |
| |
| /** @} */ |
| |
| } // namespace optimizer |
| } // namespace quickstep |
| |
| #endif // QUICKSTEP_QUERY_OPTIMIZER_RULES_ELIMINATE_EMPTY_NODE_HPP_ |