| /** |
| * 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. |
| **/ |
| |
| #ifndef QUICKSTEP_QUERY_OPTIMIZER_EXPRESSIONS_ATTRIBUTE_REFERENCE_HPP_ |
| #define QUICKSTEP_QUERY_OPTIMIZER_EXPRESSIONS_ATTRIBUTE_REFERENCE_HPP_ |
| |
| #include <memory> |
| #include <string> |
| #include <unordered_map> |
| #include <vector> |
| |
| #include "catalog/CatalogTypedefs.hpp" |
| #include "query_optimizer/expressions/ExprId.hpp" |
| #include "query_optimizer/expressions/Expression.hpp" |
| #include "query_optimizer/expressions/ExpressionType.hpp" |
| #include "query_optimizer/expressions/NamedExpression.hpp" |
| #include "utility/Macros.hpp" |
| |
| namespace quickstep { |
| |
| class CatalogAttribute; |
| class Type; |
| |
| namespace optimizer { |
| namespace expressions { |
| |
| /** \addtogroup OptimizerExpressions |
| * @{ |
| */ |
| |
| class AttributeReference; |
| typedef std::shared_ptr<const AttributeReference> AttributeReferencePtr; |
| |
| /** |
| * @brief Reference to the attribute created by an Alias or to an attribute in a |
| * base relation. |
| */ |
| class AttributeReference : public NamedExpression { |
| public: |
| ExpressionType getExpressionType() const override { |
| return ExpressionType::kAttributeReference; |
| } |
| |
| std::string getName() const override { return "AttributeReference"; } |
| |
| const Type& getValueType() const override { return type_; } |
| |
| bool isConstant() const override { return false; } |
| |
| ExpressionPtr copyWithNewChildren( |
| const std::vector<ExpressionPtr> &new_children) const override; |
| |
| std::vector<AttributeReferencePtr> getReferencedAttributes() const override; |
| |
| ::quickstep::Scalar* concretize( |
| const std::unordered_map<ExprId, const CatalogAttribute*> &substitution_map) const override; |
| |
| /** |
| * @brief Creates an immutable AttributReference. |
| * |
| * @param attribute_id The ExprId of the expression this AttributeReference |
| * references to. |
| * @param attribute_name The attribute name. This is only for printing purpose. |
| * @param attribute_alias The attribute alias (or display name). This is only |
| * for printing purpose. |
| * @param relation_name The name of the relation where the reference |
| * expression comes from. This is only for |
| * printing purpose. |
| * @param type The type of the value of the referenced expression. |
| * @return An immutable AttributeReference. |
| */ |
| static AttributeReferencePtr Create(ExprId attribute_id, |
| const std::string &attribute_name, |
| const std::string &attribute_alias, |
| const std::string &relation_name, |
| const Type &type) { |
| return AttributeReferencePtr(new AttributeReference( |
| attribute_id, attribute_name, attribute_alias, relation_name, type)); |
| } |
| |
| private: |
| AttributeReference(attribute_id attribute_id, |
| const std::string &attribute_name, |
| const std::string &attribute_alias, |
| const std::string &relation_name, |
| const Type &type) |
| : NamedExpression(attribute_id, |
| attribute_name, |
| attribute_alias, |
| relation_name), |
| type_(type) {} |
| |
| const Type &type_; |
| |
| DISALLOW_COPY_AND_ASSIGN(AttributeReference); |
| }; |
| |
| /** @} */ |
| |
| } // namespace expressions |
| } // namespace optimizer |
| } // namespace quickstep |
| |
| #endif /* QUICKSTEP_QUERY_OPTIMIZER_EXPRESSIONS_ATTRIBUTE_REFERENCE_HPP_ */ |