| /** |
| * 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_EXPRESSIONS_ATTRIBUTE_REFERENCE_HPP_ |
| #define QUICKSTEP_QUERY_OPTIMIZER_EXPRESSIONS_ATTRIBUTE_REFERENCE_HPP_ |
| |
| #include <cstddef> |
| #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 "query_optimizer/expressions/Scalar.hpp" |
| #include "utility/Macros.hpp" |
| |
| namespace quickstep { |
| |
| class CatalogAttribute; |
| class Type; |
| |
| namespace optimizer { |
| namespace expressions { |
| |
| /** \addtogroup OptimizerExpressions |
| * @{ |
| */ |
| |
| /** |
| * @brief The scope of the referenced attribute. I.e. whether the referenced |
| * attribute belongs to a local TableReference or comes from an outside |
| * TableReference. The outside case implies a correlated subquery. |
| */ |
| enum class AttributeReferenceScope { |
| kLocal = 0, |
| kOuter |
| }; |
| |
| 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; } |
| |
| /** |
| * @return The scope of the referenced attribute. |
| */ |
| const AttributeReferenceScope scope() const { |
| return scope_; |
| } |
| |
| 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; |
| |
| bool equals(const ScalarPtr &other) 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. |
| * @param scope The scope of the referenced attribute. |
| * @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, |
| const AttributeReferenceScope scope) { |
| return AttributeReferencePtr(new AttributeReference( |
| attribute_id, attribute_name, attribute_alias, relation_name, type, scope)); |
| } |
| |
| protected: |
| std::size_t computeHash() const override; |
| |
| 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: |
| AttributeReference(attribute_id attribute_id, |
| const std::string &attribute_name, |
| const std::string &attribute_alias, |
| const std::string &relation_name, |
| const Type &type, |
| const AttributeReferenceScope scope) |
| : NamedExpression(attribute_id, |
| attribute_name, |
| attribute_alias, |
| relation_name), |
| type_(type), |
| scope_(scope) {} |
| |
| const Type &type_; |
| const AttributeReferenceScope scope_; |
| |
| DISALLOW_COPY_AND_ASSIGN(AttributeReference); |
| }; |
| |
| /** @} */ |
| |
| } // namespace expressions |
| } // namespace optimizer |
| } // namespace quickstep |
| |
| #endif /* QUICKSTEP_QUERY_OPTIMIZER_EXPRESSIONS_ATTRIBUTE_REFERENCE_HPP_ */ |