| 1 | //===----------------------------------------------------------------------===// |
|---|---|
| 2 | // DuckDB |
| 3 | // |
| 4 | // duckdb/planner/expression.hpp |
| 5 | // |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #pragma once |
| 10 | |
| 11 | #include "duckdb/parser/base_expression.hpp" |
| 12 | #include "duckdb/common/types.hpp" |
| 13 | #include "duckdb/planner/plan_serialization.hpp" |
| 14 | |
| 15 | namespace duckdb { |
| 16 | class BaseStatistics; |
| 17 | class FieldWriter; |
| 18 | class FieldReader; |
| 19 | class ClientContext; |
| 20 | |
| 21 | //! The Expression class represents a bound Expression with a return type |
| 22 | class Expression : public BaseExpression { |
| 23 | public: |
| 24 | Expression(ExpressionType type, ExpressionClass expression_class, LogicalType return_type); |
| 25 | ~Expression() override; |
| 26 | |
| 27 | //! The return type of the expression |
| 28 | LogicalType return_type; |
| 29 | //! Expression statistics (if any) - ONLY USED FOR VERIFICATION |
| 30 | unique_ptr<BaseStatistics> verification_stats; |
| 31 | |
| 32 | public: |
| 33 | bool IsAggregate() const override; |
| 34 | bool IsWindow() const override; |
| 35 | bool HasSubquery() const override; |
| 36 | bool IsScalar() const override; |
| 37 | bool HasParameter() const override; |
| 38 | virtual bool HasSideEffects() const; |
| 39 | virtual bool PropagatesNullValues() const; |
| 40 | virtual bool IsFoldable() const; |
| 41 | |
| 42 | hash_t Hash() const override; |
| 43 | |
| 44 | bool Equals(const BaseExpression &other) const override { |
| 45 | if (!BaseExpression::Equals(other)) { |
| 46 | return false; |
| 47 | } |
| 48 | return return_type == ((Expression &)other).return_type; |
| 49 | } |
| 50 | static bool Equals(const Expression &left, const Expression &right) { |
| 51 | return left.Equals(other: right); |
| 52 | } |
| 53 | static bool Equals(const unique_ptr<Expression> &left, const unique_ptr<Expression> &right); |
| 54 | static bool ListEquals(const vector<unique_ptr<Expression>> &left, const vector<unique_ptr<Expression>> &right); |
| 55 | //! Create a copy of this expression |
| 56 | virtual unique_ptr<Expression> Copy() = 0; |
| 57 | |
| 58 | //! Serializes an Expression to a stand-alone binary blob |
| 59 | void Serialize(Serializer &serializer) const; |
| 60 | //! Serializes an Expression to a stand-alone binary blob |
| 61 | virtual void Serialize(FieldWriter &writer) const = 0; |
| 62 | |
| 63 | //! Deserializes a blob back into an Expression [CAN THROW: |
| 64 | //! SerializationException] |
| 65 | static unique_ptr<Expression> Deserialize(Deserializer &source, PlanDeserializationState &state); |
| 66 | |
| 67 | protected: |
| 68 | //! Copy base Expression properties from another expression to this one, |
| 69 | //! used in Copy method |
| 70 | void CopyProperties(Expression &other) { |
| 71 | type = other.type; |
| 72 | expression_class = other.expression_class; |
| 73 | alias = other.alias; |
| 74 | return_type = other.return_type; |
| 75 | } |
| 76 | }; |
| 77 | |
| 78 | } // namespace duckdb |
| 79 |