query_optimizer/expressions/CommonSubexpression.cpp

/**
 * 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.
 **/

#include "query_optimizer/expressions/CommonSubexpression.hpp"

#include <memory>
#include <string>
#include <unordered_map>
#include <vector>

#include "expressions/scalar/ScalarSharedExpression.hpp"
#include "query_optimizer/OptimizerTree.hpp"
#include "query_optimizer/expressions/ExprId.hpp"
#include "query_optimizer/expressions/Expression.hpp"
#include "query_optimizer/expressions/PatternMatcher.hpp"
#include "query_optimizer/expressions/Scalar.hpp"

#include "glog/logging.h"

namespace quickstep {
namespace optimizer {
namespace expressions {

ExpressionPtr CommonSubexpression::copyWithNewChildren(
    const std::vector<ExpressionPtr> &new_children) const {
  DCHECK_EQ(new_children.size(), children().size());
  DCHECK(SomeScalar::Matches(new_children[0]));
  return CommonSubexpression::Create(
      common_subexpression_id_,
      std::static_pointer_cast<const Scalar>(new_children[0]));
}

::quickstep::Scalar* CommonSubexpression::concretize(
    const std::unordered_map<ExprId, const CatalogAttribute*> &substitution_map) const {
  return new ::quickstep::ScalarSharedExpression(
      static_cast<int>(common_subexpression_id_),
      operand_->concretize(substitution_map));
}

void CommonSubexpression::getFieldStringItems(
    std::vector<std::string> *inline_field_names,
    std::vector<std::string> *inline_field_values,
    std::vector<std::string> *non_container_child_field_names,
    std::vector<OptimizerTreeBaseNodePtr> *non_container_child_fields,
    std::vector<std::string> *container_child_field_names,
    std::vector<std::vector<OptimizerTreeBaseNodePtr>> *container_child_fields) const {
  inline_field_names->push_back("common_subexpression_id");
  inline_field_values->push_back(std::to_string(common_subexpression_id_));

  non_container_child_field_names->push_back("Operand");
  non_container_child_fields->push_back(operand_);
}

}  // namespace expressions
}  // namespace optimizer
}  // namespace quickstep