#pragma once #include #include namespace DB { /** Description of the table. * Is not thread safe. See IStorage::lockStructure (). */ class ITableDeclaration { public: const ColumnsDescription & getColumns() const; void setColumns(ColumnsDescription columns_); const IndicesDescription & getIndices() const; void setIndices(IndicesDescription indices_); /// NOTE: These methods should include virtual columns, but should NOT include ALIAS columns /// (they are treated separately). virtual NameAndTypePair getColumn(const String & column_name) const; virtual bool hasColumn(const String & column_name) const; Block getSampleBlock() const; Block getSampleBlockNonMaterialized() const; /// Including virtual and alias columns. Block getSampleBlockForColumns(const Names & column_names) const; /** Verify that all the requested names are in the table and are set correctly. * (the list of names is not empty and the names do not repeat) */ void check(const Names & column_names) const; /** Check that all the requested names are in the table and have the correct types. */ void check(const NamesAndTypesList & columns) const; /** Check that all names from the intersection of `names` and `columns` are in the table and have the same types. */ void check(const NamesAndTypesList & columns, const Names & column_names) const; /** Check that the data block contains all the columns of the table with the correct types, * contains only the columns of the table, and all the columns are different. * If need_all, checks that all the columns of the table are in the block. */ void check(const Block & block, bool need_all = false) const; ITableDeclaration() = default; explicit ITableDeclaration(ColumnsDescription columns_); virtual ~ITableDeclaration() = default; private: ColumnsDescription columns; IndicesDescription indices; }; }