| /** |
| * Copyright 2016, Quickstep Research Group, Computer Sciences Department, |
| * University of Wisconsin—Madison. |
| * |
| * 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. |
| **/ |
| |
| #ifndef QUICKSTEP_QUERY_OPTIMIZER_EXPRESSIONS_EXISTS_HPP_ |
| #define QUICKSTEP_QUERY_OPTIMIZER_EXPRESSIONS_EXISTS_HPP_ |
| |
| #include <memory> |
| #include <string> |
| #include <unordered_map> |
| #include <vector> |
| |
| #include "query_optimizer/OptimizerTree.hpp" |
| #include "query_optimizer/expressions/AttributeReference.hpp" |
| #include "query_optimizer/expressions/ExprId.hpp" |
| #include "query_optimizer/expressions/Expression.hpp" |
| #include "query_optimizer/expressions/ExpressionType.hpp" |
| #include "query_optimizer/expressions/Predicate.hpp" |
| #include "query_optimizer/expressions/SubqueryExpression.hpp" |
| #include "utility/Macros.hpp" |
| |
| #include "glog/logging.h" |
| |
| namespace quickstep { |
| |
| class CatalogAttribute; |
| class Predicate; |
| |
| namespace optimizer { |
| namespace expressions { |
| |
| /** \addtogroup OptimizerExpressions |
| * @{ |
| */ |
| |
| class Exists; |
| typedef std::shared_ptr<const Exists> ExistsPtr; |
| |
| /** |
| * @brief EXISTS predicate expression. |
| */ |
| class Exists : public Predicate { |
| public: |
| ExpressionType getExpressionType() const override { |
| return ExpressionType::kExists; |
| } |
| |
| std::string getName() const override { |
| return "Exists"; |
| } |
| |
| bool isConstant() const override { |
| return false; |
| } |
| |
| /** |
| * @return The subquery expression for this EXISTS predicate. |
| */ |
| const SubqueryExpressionPtr& exists_subquery() const { |
| return exists_subquery_; |
| } |
| |
| ExpressionPtr copyWithNewChildren( |
| const std::vector<ExpressionPtr> &new_children) const override { |
| DCHECK_EQ(1u, new_children.size()); |
| return Create(std::static_pointer_cast<const SubqueryExpression>(new_children[0])); |
| } |
| |
| std::vector<AttributeReferencePtr> getReferencedAttributes() const override { |
| return {}; |
| } |
| |
| ::quickstep::Predicate* concretize( |
| const std::unordered_map<ExprId, const CatalogAttribute*> &substitution_map) const override; |
| |
| /** |
| * @brief Create an Exists predicate expression. |
| * |
| * @param exists_subquery The subquery expression for this EXISTS predicate. |
| * @return An immutable Exists expression node. |
| */ |
| static ExistsPtr Create(const SubqueryExpressionPtr &exists_subquery) { |
| return ExistsPtr(new Exists(exists_subquery)); |
| } |
| |
| protected: |
| void 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 override; |
| |
| private: |
| explicit Exists(const SubqueryExpressionPtr &exists_subquery) |
| : exists_subquery_(exists_subquery) { |
| addChild(exists_subquery_); |
| } |
| |
| SubqueryExpressionPtr exists_subquery_; |
| |
| DISALLOW_COPY_AND_ASSIGN(Exists); |
| }; |
| |
| /** @} */ |
| |
| } // namespace expressions |
| } // namespace optimizer |
| } // namespace quickstep |
| |
| |
| #endif /* QUICKSTEP_QUERY_OPTIMIZER_EXPRESSIONS_EXISTS_HPP_ */ |