query_optimizer/physical/Sort.cpp

/**
 *   Copyright 2011-2015 Quickstep Technologies LLC.
 *   Copyright 2015 Pivotal Software, Inc.
 *
 *   Licensed 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/physical/Sort.hpp"

#include <string>
#include <vector>

#include "query_optimizer/OptimizerTree.hpp"
#include "query_optimizer/expressions/ExpressionUtil.hpp"
#include "query_optimizer/physical/Physical.hpp"
#include "utility/Cast.hpp"

namespace quickstep {
namespace optimizer {
namespace physical {

bool Sort::maybeCopyWithPrunedExpressions(
    const expressions::UnorderedNamedExpressionSet &referenced_attributes,
    PhysicalPtr *output) const {
  std::vector<expressions::AttributeReferencePtr> new_non_sort_attributes;
  for (const expressions::AttributeReferencePtr &non_sort_attribute : non_sort_attributes_) {
    if (referenced_attributes.find(non_sort_attribute) != referenced_attributes.end()) {
      new_non_sort_attributes.emplace_back(non_sort_attribute);
    }
  }
  if (new_non_sort_attributes.size() != non_sort_attributes_.size()) {
    *output = Create(input_,
                     sort_attributes_,
                     new_non_sort_attributes,
                     sort_ascending_,
                     nulls_first_flags_,
                     limit_);
    return true;
  }
  return false;
}

void Sort::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 {
  non_container_child_field_names->push_back("input");
  non_container_child_fields->push_back(input_);

  inline_field_names->push_back("is_ascending");
  std::string ascending_list("[");
  for (bool is_ascending : sort_ascending_) {
    if (is_ascending) {
      ascending_list.append("true,");
    } else {
      ascending_list.append("false,");
    }
  }
  ascending_list.pop_back();
  ascending_list.append("]");
  inline_field_values->push_back(ascending_list);

  inline_field_names->push_back("nulls_first");
  std::string nulls_first_flags("[");
  for (bool nulls_first_flag : nulls_first_flags_) {
    if (nulls_first_flag) {
      nulls_first_flags.append("true,");
    } else {
      nulls_first_flags.append("false,");
    }
  }
  nulls_first_flags.pop_back();
  nulls_first_flags.append("]");
  inline_field_values->push_back(nulls_first_flags);

  if (limit_ != -1) {
    inline_field_names->push_back("limit");
    inline_field_values->push_back(std::to_string(limit_));
  }

  container_child_field_names->push_back("sort_attributes");
  container_child_fields->push_back(CastSharedPtrVector<OptimizerTreeBase>(sort_attributes_));
}

}  // namespace physical
}  // namespace optimizer
}  // namespace quickstep