query_optimizer/LogicalGenerator.hpp

/**
 * 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_LOGICAL_GENERATOR_HPP_
#define QUICKSTEP_QUERY_OPTIMIZER_LOGICAL_GENERATOR_HPP_

#include "query_optimizer/logical/Logical.hpp"
#include "utility/Macros.hpp"

namespace quickstep {

class CatalogDatabase;
class ParseStatement;

namespace optimizer {

class OptimizerContext;

/** \addtogroup QueryOptimizer
 *  @{
 */

/**
 * @brief Generates a logical plan from a parse tree.
 */
class LogicalGenerator {
 public:
  /**
   * @brief Constructor.
   *
   * @param optimizer_context The optimizer context.
   */
  explicit LogicalGenerator(OptimizerContext *optimizer_context);

  /**
   * @brief Destructor.
   */
  ~LogicalGenerator();

  /**
   * @return The current logical plan.
   */
  const logical::LogicalPtr& logical_plan() const { return logical_plan_; }

  /**
   * @brief Converts the parse tree to a logical plan and optimizes the logical
   *        plan by using rules.
   *
   * @param catalog_database The catalog database where this query is executed.
   * @param parse_statement The parse tree to be converted.
   * @return An optimized logical plan.
   */
  logical::LogicalPtr generatePlan(const CatalogDatabase &catalog_database,
                                   const ParseStatement &parse_statement);

 private:
  /**
   * @brief Applies rules to the logical plan.
   */
  void optimizePlan();

  OptimizerContext *optimizer_context_;
  logical::LogicalPtr logical_plan_;

  DISALLOW_COPY_AND_ASSIGN(LogicalGenerator);
};

/** @} */

}  // namespace optimizer
}  // namespace quickstep

#endif /* QUICKSTEP_QUERY_OPTIMIZER_LOGICAL_GENERATOR_HPP_ */