#pragma once #include #include #include #include #include #include namespace DB { class ASTSelectQuery; class TableJoin; struct SelectQueryOptions; struct StorageInMemoryMetadata; using StorageMetadataPtr = std::shared_ptr; /// Joined tables' columns resolver. /// We want to get each table structure at most once per table occurrence. Or even better once per table. /// TODO: joins tree with costs to change joins order by CBO. class JoinedTables { public: JoinedTables(ContextPtr context, const ASTSelectQuery & select_query_, bool include_all_columns_ = false, bool is_create_parameterized_view_ = false); void reset(const ASTSelectQuery & select_query); StoragePtr getLeftTableStorage(); bool resolveTables(); /// Make fake tables_with_columns[0] in case we have predefined input in InterpreterSelectQuery void makeFakeTable(StoragePtr storage, const StorageMetadataPtr & metadata_snapshot, const Block & source_header); std::shared_ptr makeTableJoin(const ASTSelectQuery & select_query); const TablesWithColumns & tablesWithColumns() const { return tables_with_columns; } bool isLeftTableSubquery() const; bool isLeftTableFunction() const; size_t tablesCount() const { return table_expressions.size(); } void rewriteDistributedInAndJoins(ASTPtr & query); std::unique_ptr makeLeftTableSubquery(const SelectQueryOptions & select_options); private: ContextPtr context; std::vector table_expressions; TablesWithColumns tables_with_columns; const bool include_all_columns; /// Legacy (duplicated left table values) ASTPtr left_table_expression; std::optional left_db_and_table; const ASTSelectQuery & select_query; const bool is_create_parameterized_view; }; }