#include #include #include "Common/Exception.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include namespace DB { namespace ErrorCodes { extern const int TABLE_ALREADY_EXISTS; extern const int DICTIONARY_ALREADY_EXISTS; extern const int EMPTY_LIST_OF_COLUMNS_PASSED; extern const int INCORRECT_QUERY; extern const int UNKNOWN_DATABASE_ENGINE; extern const int DUPLICATE_COLUMN; extern const int DATABASE_ALREADY_EXISTS; extern const int BAD_ARGUMENTS; extern const int BAD_DATABASE_FOR_TEMPORARY_TABLE; extern const int SUSPICIOUS_TYPE_FOR_LOW_CARDINALITY; extern const int ILLEGAL_SYNTAX_FOR_DATA_TYPE; extern const int ILLEGAL_COLUMN; extern const int LOGICAL_ERROR; extern const int UNKNOWN_DATABASE; extern const int PATH_ACCESS_DENIED; extern const int NOT_IMPLEMENTED; extern const int ENGINE_REQUIRED; extern const int UNKNOWN_STORAGE; extern const int SYNTAX_ERROR; extern const int SUPPORT_IS_DISABLED; } namespace fs = std::filesystem; InterpreterCreateQuery::InterpreterCreateQuery(const ASTPtr & query_ptr_, ContextMutablePtr context_) : WithMutableContext(context_), query_ptr(query_ptr_) { } BlockIO InterpreterCreateQuery::createDatabase(ASTCreateQuery & create) { String database_name = create.getDatabase(); auto guard = DatabaseCatalog::instance().getDDLGuard(database_name, ""); /// Database can be created before or it can be created concurrently in another thread, while we were waiting in DDLGuard if (DatabaseCatalog::instance().isDatabaseExist(database_name)) { if (create.if_not_exists) return {}; else throw Exception(ErrorCodes::DATABASE_ALREADY_EXISTS, "Database {} already exists.", database_name); } /// Will write file with database metadata, if needed. String database_name_escaped = escapeForFileName(database_name); fs::path metadata_path = fs::canonical(getContext()->getPath()); fs::path metadata_file_tmp_path = metadata_path / "metadata" / (database_name_escaped + ".sql.tmp"); fs::path metadata_file_path = metadata_path / "metadata" / (database_name_escaped + ".sql"); if (!create.storage && create.attach) { if (!fs::exists(metadata_file_path)) throw Exception(ErrorCodes::UNKNOWN_DATABASE_ENGINE, "Database engine must be specified for ATTACH DATABASE query"); /// Short syntax: try read database definition from file auto ast = DatabaseOnDisk::parseQueryFromMetadata(nullptr, getContext(), metadata_file_path); create = ast->as(); if (create.table || !create.storage) throw Exception(ErrorCodes::INCORRECT_QUERY, "Metadata file {} contains incorrect CREATE DATABASE query", metadata_file_path.string()); create.attach = true; create.attach_short_syntax = true; create.setDatabase(database_name); } else if (!create.storage) { /// For new-style databases engine is explicitly specified in .sql /// When attaching old-style database during server startup, we must always use Ordinary engine if (create.attach) throw Exception(ErrorCodes::UNKNOWN_DATABASE_ENGINE, "Database engine must be specified for ATTACH DATABASE query"); auto engine = std::make_shared(); auto storage = std::make_shared(); engine->name = "Atomic"; engine->no_empty_args = true; storage->set(storage->engine, engine); create.set(create.storage, storage); } else if ((create.columns_list && ((create.columns_list->indices && !create.columns_list->indices->children.empty()) || (create.columns_list->projections && !create.columns_list->projections->children.empty())))) { /// Currently, there are no database engines, that support any arguments. throw Exception(ErrorCodes::UNKNOWN_DATABASE_ENGINE, "Unknown database engine: {}", serializeAST(*create.storage)); } if (create.storage && !create.storage->engine) throw Exception(ErrorCodes::INCORRECT_QUERY, "Database engine must be specified"); if (create.storage->engine->name == "Atomic" || create.storage->engine->name == "Replicated" || create.storage->engine->name == "MaterializedPostgreSQL") { if (create.attach && create.uuid == UUIDHelpers::Nil) throw Exception(ErrorCodes::INCORRECT_QUERY, "UUID must be specified for ATTACH. " "If you want to attach existing database, use just ATTACH DATABASE {};", create.getDatabase()); else if (create.uuid == UUIDHelpers::Nil) create.uuid = UUIDHelpers::generateV4(); metadata_path = metadata_path / "store" / DatabaseCatalog::getPathForUUID(create.uuid); if (!create.attach && fs::exists(metadata_path)) throw Exception(ErrorCodes::DATABASE_ALREADY_EXISTS, "Metadata directory {} already exists", metadata_path.string()); } else if (create.storage->engine->name == "MaterializeMySQL" || create.storage->engine->name == "MaterializedMySQL") { /// It creates nested database with Ordinary or Atomic engine depending on UUID in query and default engine setting. /// Do nothing if it's an internal ATTACH on server startup or short-syntax ATTACH query from user, /// because we got correct query from the metadata file in this case. /// If we got query from user, then normalize it first. bool attach_from_user = create.attach && !internal && !create.attach_short_syntax; bool create_from_user = !create.attach; if (create_from_user) { if (create.uuid == UUIDHelpers::Nil) create.uuid = UUIDHelpers::generateV4(); /// Will enable Atomic engine for nested database } else if (attach_from_user && create.uuid == UUIDHelpers::Nil) { /// Ambiguity is possible: should we attach nested database as Ordinary /// or throw "UUID must be specified" for Atomic? So we suggest short syntax for Ordinary. throw Exception(ErrorCodes::INCORRECT_QUERY, "Use short attach syntax ('ATTACH DATABASE name;' without engine) " "to attach existing database or specify UUID to attach new database with Atomic engine"); } /// Set metadata path according to nested engine if (create.uuid == UUIDHelpers::Nil) metadata_path = metadata_path / "metadata" / database_name_escaped; else metadata_path = metadata_path / "store" / DatabaseCatalog::getPathForUUID(create.uuid); } else { bool is_on_cluster = getContext()->getClientInfo().query_kind == ClientInfo::QueryKind::SECONDARY_QUERY; if (create.uuid != UUIDHelpers::Nil && !is_on_cluster) throw Exception(ErrorCodes::INCORRECT_QUERY, "Ordinary database engine does not support UUID"); /// Ignore UUID if it's ON CLUSTER query create.uuid = UUIDHelpers::Nil; metadata_path = metadata_path / "metadata" / database_name_escaped; } if (create.storage->engine->name == "Replicated" && !internal && !create.attach && create.storage->engine->arguments) { /// Fill in default parameters if (create.storage->engine->arguments->children.size() == 1) create.storage->engine->arguments->children.push_back(std::make_shared("{shard}")); if (create.storage->engine->arguments->children.size() == 2) create.storage->engine->arguments->children.push_back(std::make_shared("{replica}")); } if ((create.storage->engine->name == "MaterializeMySQL" || create.storage->engine->name == "MaterializedMySQL") && !getContext()->getSettingsRef().allow_experimental_database_materialized_mysql && !internal && !create.attach) { throw Exception(ErrorCodes::UNKNOWN_DATABASE_ENGINE, "MaterializedMySQL is an experimental database engine. " "Enable allow_experimental_database_materialized_mysql to use it"); } if (create.storage->engine->name == "Replicated" && !getContext()->getSettingsRef().allow_experimental_database_replicated && !internal && !create.attach) { throw Exception(ErrorCodes::UNKNOWN_DATABASE_ENGINE, "Replicated is an experimental database engine. " "Enable allow_experimental_database_replicated to use it"); } if (create.storage->engine->name == "MaterializedPostgreSQL" && !getContext()->getSettingsRef().allow_experimental_database_materialized_postgresql && !internal && !create.attach) { throw Exception(ErrorCodes::UNKNOWN_DATABASE_ENGINE, "MaterializedPostgreSQL is an experimental database engine. " "Enable allow_experimental_database_materialized_postgresql to use it"); } bool need_write_metadata = !create.attach || !fs::exists(metadata_file_path); bool need_lock_uuid = internal || need_write_metadata; auto mode = getLoadingStrictnessLevel(create.attach, force_attach, has_force_restore_data_flag); /// Lock uuid, so we will known it's already in use. /// We do it when attaching databases on server startup (internal) and on CREATE query (!create.attach); TemporaryLockForUUIDDirectory uuid_lock; if (need_lock_uuid) uuid_lock = TemporaryLockForUUIDDirectory{create.uuid}; else if (create.uuid != UUIDHelpers::Nil && !DatabaseCatalog::instance().hasUUIDMapping(create.uuid)) throw Exception(ErrorCodes::LOGICAL_ERROR, "Cannot find UUID mapping for {}, it's a bug", create.uuid); DatabasePtr database = DatabaseFactory::get(create, metadata_path / "", getContext()); if (create.uuid != UUIDHelpers::Nil) create.setDatabase(TABLE_WITH_UUID_NAME_PLACEHOLDER); if (need_write_metadata) { create.attach = true; create.if_not_exists = false; WriteBufferFromOwnString statement_buf; formatAST(create, statement_buf, false); writeChar('\n', statement_buf); String statement = statement_buf.str(); /// Exclusive flag guarantees, that database is not created right now in another thread. WriteBufferFromFile out(metadata_file_tmp_path, statement.size(), O_WRONLY | O_CREAT | O_EXCL); writeString(statement, out); out.next(); if (getContext()->getSettingsRef().fsync_metadata) out.sync(); out.close(); } /// We attach database before loading it's tables, so do not allow concurrent DDL queries auto db_guard = DatabaseCatalog::instance().getExclusiveDDLGuardForDatabase(database_name); bool added = false; bool renamed = false; try { /// TODO Attach db only after it was loaded. Now it's not possible because of view dependencies DatabaseCatalog::instance().attachDatabase(database_name, database); added = true; if (need_write_metadata) { /// Prevents from overwriting metadata of detached database renameNoReplace(metadata_file_tmp_path, metadata_file_path); renamed = true; } if (!load_database_without_tables) { /// We use global context here, because storages lifetime is bigger than query context lifetime TablesLoader loader{getContext()->getGlobalContext(), {{database_name, database}}, mode}; loader.loadTables(); loader.startupTables(); } } catch (...) { if (renamed) { [[maybe_unused]] bool removed = fs::remove(metadata_file_path); assert(removed); } if (added) DatabaseCatalog::instance().detachDatabase(getContext(), database_name, false, false); throw; } return {}; } ASTPtr InterpreterCreateQuery::formatColumns(const NamesAndTypesList & columns) { auto columns_list = std::make_shared(); for (const auto & column : columns) { const auto column_declaration = std::make_shared(); column_declaration->name = column.name; ParserDataType type_parser; String type_name = column.type->getName(); const char * pos = type_name.data(); const char * end = pos + type_name.size(); column_declaration->type = parseQuery(type_parser, pos, end, "data type", 0, DBMS_DEFAULT_MAX_PARSER_DEPTH); columns_list->children.emplace_back(column_declaration); } return columns_list; } ASTPtr InterpreterCreateQuery::formatColumns(const NamesAndTypesList & columns, const NamesAndAliases & alias_columns) { std::shared_ptr columns_list = std::static_pointer_cast(formatColumns(columns)); for (const auto & alias_column : alias_columns) { const auto column_declaration = std::make_shared(); column_declaration->name = alias_column.name; ParserDataType type_parser; String type_name = alias_column.type->getName(); const char * type_pos = type_name.data(); const char * type_end = type_pos + type_name.size(); column_declaration->type = parseQuery(type_parser, type_pos, type_end, "data type", 0, DBMS_DEFAULT_MAX_PARSER_DEPTH); column_declaration->default_specifier = "ALIAS"; const auto & alias = alias_column.expression; const char * alias_pos = alias.data(); const char * alias_end = alias_pos + alias.size(); ParserExpression expression_parser; column_declaration->default_expression = parseQuery(expression_parser, alias_pos, alias_end, "expression", 0, DBMS_DEFAULT_MAX_PARSER_DEPTH); column_declaration->children.push_back(column_declaration->default_expression); columns_list->children.emplace_back(column_declaration); } return columns_list; } ASTPtr InterpreterCreateQuery::formatColumns(const ColumnsDescription & columns) { auto columns_list = std::make_shared(); for (const auto & column : columns) { const auto column_declaration = std::make_shared(); ASTPtr column_declaration_ptr{column_declaration}; column_declaration->name = column.name; ParserDataType type_parser; String type_name = column.type->getName(); const char * type_name_pos = type_name.data(); const char * type_name_end = type_name_pos + type_name.size(); column_declaration->type = parseQuery(type_parser, type_name_pos, type_name_end, "data type", 0, DBMS_DEFAULT_MAX_PARSER_DEPTH); if (column.default_desc.expression) { column_declaration->default_specifier = toString(column.default_desc.kind); column_declaration->default_expression = column.default_desc.expression->clone(); column_declaration->children.push_back(column_declaration->default_expression); } column_declaration->ephemeral_default = column.default_desc.ephemeral_default; if (!column.comment.empty()) { column_declaration->comment = std::make_shared(Field(column.comment)); column_declaration->children.push_back(column_declaration->comment); } if (column.codec) { column_declaration->codec = column.codec; column_declaration->children.push_back(column_declaration->codec); } if (column.ttl) { column_declaration->ttl = column.ttl; column_declaration->children.push_back(column_declaration->ttl); } columns_list->children.push_back(column_declaration_ptr); } return columns_list; } ASTPtr InterpreterCreateQuery::formatIndices(const IndicesDescription & indices) { auto res = std::make_shared(); for (const auto & index : indices) res->children.push_back(index.definition_ast->clone()); return res; } ASTPtr InterpreterCreateQuery::formatConstraints(const ConstraintsDescription & constraints) { auto res = std::make_shared(); for (const auto & constraint : constraints.getConstraints()) res->children.push_back(constraint->clone()); return res; } ASTPtr InterpreterCreateQuery::formatProjections(const ProjectionsDescription & projections) { auto res = std::make_shared(); for (const auto & projection : projections) res->children.push_back(projection.definition_ast->clone()); return res; } ColumnsDescription InterpreterCreateQuery::getColumnsDescription( const ASTExpressionList & columns_ast, ContextPtr context_, bool attach) { /// First, deduce implicit types. /** all default_expressions as a single expression list, * mixed with conversion-columns for each explicitly specified type */ ASTPtr default_expr_list = std::make_shared(); NamesAndTypesList column_names_and_types; bool make_columns_nullable = !attach && context_->getSettingsRef().data_type_default_nullable; for (const auto & ast : columns_ast.children) { const auto & col_decl = ast->as(); if (col_decl.collation && !context_->getSettingsRef().compatibility_ignore_collation_in_create_table) { throw Exception(ErrorCodes::NOT_IMPLEMENTED, "Cannot support collation, please set compatibility_ignore_collation_in_create_table=true"); } DataTypePtr column_type = nullptr; if (col_decl.type) { column_type = DataTypeFactory::instance().get(col_decl.type); if (attach) setVersionToAggregateFunctions(column_type, true); if (col_decl.null_modifier) { if (column_type->isNullable()) throw Exception(ErrorCodes::ILLEGAL_SYNTAX_FOR_DATA_TYPE, "Can't use [NOT] NULL modifier with Nullable type"); if (*col_decl.null_modifier) column_type = makeNullable(column_type); } else if (make_columns_nullable) { column_type = makeNullable(column_type); } else if (!hasNullable(column_type) && col_decl.default_specifier == "DEFAULT" && col_decl.default_expression && col_decl.default_expression->as() && col_decl.default_expression->as()->value.isNull()) { if (column_type->lowCardinality()) { const auto * low_cardinality_type = typeid_cast(column_type.get()); assert(low_cardinality_type); column_type = std::make_shared(makeNullable(low_cardinality_type->getDictionaryType())); } else column_type = makeNullable(column_type); } column_names_and_types.emplace_back(col_decl.name, column_type); } else { /// we're creating dummy DataTypeUInt8 in order to prevent the NullPointerException in ExpressionActions column_names_and_types.emplace_back(col_decl.name, std::make_shared()); } /// add column to postprocessing if there is a default_expression specified if (col_decl.default_expression) { /** For columns with explicitly-specified type create two expressions: * 1. default_expression aliased as column name with _tmp suffix * 2. conversion of expression (1) to explicitly-specified type alias as column name */ if (col_decl.type) { const auto & final_column_name = col_decl.name; const auto tmp_column_name = final_column_name + "_tmp_alter" + toString(randomSeed()); const auto * data_type_ptr = column_names_and_types.back().type.get(); default_expr_list->children.emplace_back( setAlias(addTypeConversionToAST(std::make_shared(tmp_column_name), data_type_ptr->getName()), final_column_name)); default_expr_list->children.emplace_back( setAlias(col_decl.default_expression->clone(), tmp_column_name)); } else default_expr_list->children.emplace_back(setAlias(col_decl.default_expression->clone(), col_decl.name)); } } Block defaults_sample_block; /// set missing types and wrap default_expression's in a conversion-function if necessary if (!default_expr_list->children.empty()) defaults_sample_block = validateColumnsDefaultsAndGetSampleBlock(default_expr_list, column_names_and_types, context_); bool sanity_check_compression_codecs = !attach && !context_->getSettingsRef().allow_suspicious_codecs; bool allow_experimental_codecs = attach || context_->getSettingsRef().allow_experimental_codecs; bool enable_deflate_qpl_codec = attach || context_->getSettingsRef().enable_deflate_qpl_codec; ColumnsDescription res; auto name_type_it = column_names_and_types.begin(); for (const auto * ast_it = columns_ast.children.begin(); ast_it != columns_ast.children.end(); ++ast_it, ++name_type_it) { ColumnDescription column; auto & col_decl = (*ast_it)->as(); column.name = col_decl.name; /// ignore or not other database extensions depending on compatibility settings if (col_decl.default_specifier == "AUTO_INCREMENT" && !context_->getSettingsRef().compatibility_ignore_auto_increment_in_create_table) { throw Exception(ErrorCodes::SYNTAX_ERROR, "AUTO_INCREMENT is not supported. To ignore the keyword " "in column declaration, set `compatibility_ignore_auto_increment_in_create_table` to true"); } if (col_decl.default_expression) { if (context_->hasQueryContext() && context_->getQueryContext().get() == context_.get()) { /// Normalize query only for original CREATE query, not on metadata loading. /// And for CREATE query we can pass local context, because result will not change after restart. NormalizeAndEvaluateConstantsVisitor::Data visitor_data{context_}; NormalizeAndEvaluateConstantsVisitor visitor(visitor_data); visitor.visit(col_decl.default_expression); } ASTPtr default_expr = col_decl.default_expression->clone(); if (col_decl.type) column.type = name_type_it->type; else { column.type = defaults_sample_block.getByName(column.name).type; /// set nullability for case of column declaration w/o type but with default expression if ((col_decl.null_modifier && *col_decl.null_modifier) || make_columns_nullable) column.type = makeNullable(column.type); } column.default_desc.kind = columnDefaultKindFromString(col_decl.default_specifier); column.default_desc.expression = default_expr; column.default_desc.ephemeral_default = col_decl.ephemeral_default; } else if (col_decl.type) column.type = name_type_it->type; else throw Exception(ErrorCodes::LOGICAL_ERROR, "Neither default value expression nor type is provided for a column"); if (col_decl.comment) column.comment = col_decl.comment->as().value.get(); if (col_decl.codec) { if (col_decl.default_specifier == "ALIAS") throw Exception(ErrorCodes::BAD_ARGUMENTS, "Cannot specify codec for column type ALIAS"); column.codec = CompressionCodecFactory::instance().validateCodecAndGetPreprocessedAST( col_decl.codec, column.type, sanity_check_compression_codecs, allow_experimental_codecs, enable_deflate_qpl_codec); } if (col_decl.ttl) column.ttl = col_decl.ttl; res.add(std::move(column)); } if (!attach && context_->getSettingsRef().flatten_nested) res.flattenNested(); if (res.getAllPhysical().empty()) throw Exception(ErrorCodes::EMPTY_LIST_OF_COLUMNS_PASSED, "Cannot CREATE table without physical columns"); return res; } ConstraintsDescription InterpreterCreateQuery::getConstraintsDescription(const ASTExpressionList * constraints) { ASTs constraints_data; if (constraints) for (const auto & constraint : constraints->children) constraints_data.push_back(constraint->clone()); return ConstraintsDescription{constraints_data}; } InterpreterCreateQuery::TableProperties InterpreterCreateQuery::getTablePropertiesAndNormalizeCreateQuery(ASTCreateQuery & create) const { /// Set the table engine if it was not specified explicitly. setEngine(create); /// We have to check access rights again (in case engine was changed). if (create.storage) { auto source_access_type = StorageFactory::instance().getSourceAccessType(create.storage->engine->name); if (source_access_type != AccessType::NONE) getContext()->checkAccess(source_access_type); } TableProperties properties; TableLockHolder as_storage_lock; if (create.columns_list) { if (create.as_table_function && (create.columns_list->indices || create.columns_list->constraints)) throw Exception(ErrorCodes::INCORRECT_QUERY, "Indexes and constraints are not supported for table functions"); /// Dictionaries have dictionary_attributes_list instead of columns_list assert(!create.is_dictionary); if (create.columns_list->columns) { properties.columns = getColumnsDescription(*create.columns_list->columns, getContext(), create.attach); } if (create.columns_list->indices) for (const auto & index : create.columns_list->indices->children) { IndexDescription index_desc = IndexDescription::getIndexFromAST(index->clone(), properties.columns, getContext()); const auto & settings = getContext()->getSettingsRef(); if (index_desc.type == INVERTED_INDEX_NAME && !settings.allow_experimental_inverted_index) { throw Exception(ErrorCodes::SUPPORT_IS_DISABLED, "Experimental Inverted Index feature is not enabled (the setting 'allow_experimental_inverted_index')"); } if (index_desc.type == "annoy" && !settings.allow_experimental_annoy_index) throw Exception(ErrorCodes::INCORRECT_QUERY, "Annoy index is disabled. Turn on allow_experimental_annoy_index"); properties.indices.push_back(index_desc); } if (create.columns_list->projections) for (const auto & projection_ast : create.columns_list->projections->children) { auto projection = ProjectionDescription::getProjectionFromAST(projection_ast, properties.columns, getContext()); properties.projections.add(std::move(projection)); } properties.constraints = getConstraintsDescription(create.columns_list->constraints); } else if (!create.as_table.empty()) { String as_database_name = getContext()->resolveDatabase(create.as_database); StoragePtr as_storage = DatabaseCatalog::instance().getTable({as_database_name, create.as_table}, getContext()); /// as_storage->getColumns() and setEngine(...) must be called under structure lock of other_table for CREATE ... AS other_table. as_storage_lock = as_storage->lockForShare(getContext()->getCurrentQueryId(), getContext()->getSettingsRef().lock_acquire_timeout); auto as_storage_metadata = as_storage->getInMemoryMetadataPtr(); properties.columns = as_storage_metadata->getColumns(); /// Secondary indices and projections make sense only for MergeTree family of storage engines. /// We should not copy them for other storages. if (create.storage && endsWith(create.storage->engine->name, "MergeTree")) { properties.indices = as_storage_metadata->getSecondaryIndices(); properties.projections = as_storage_metadata->getProjections().clone(); } else { /// Only MergeTree support TTL properties.columns.resetColumnTTLs(); } properties.constraints = as_storage_metadata->getConstraints(); } else if (create.select) { Block as_select_sample; if (getContext()->getSettingsRef().allow_experimental_analyzer) { as_select_sample = InterpreterSelectQueryAnalyzer::getSampleBlock(create.select->clone(), getContext()); } else { as_select_sample = InterpreterSelectWithUnionQuery::getSampleBlock(create.select->clone(), getContext(), false /* is_subquery */, create.isParameterizedView()); } properties.columns = ColumnsDescription(as_select_sample.getNamesAndTypesList()); } else if (create.as_table_function) { /// Table function without columns list. auto table_function_ast = create.as_table_function->ptr(); auto table_function = TableFunctionFactory::instance().get(table_function_ast, getContext()); properties.columns = table_function->getActualTableStructure(getContext()); } else if (create.is_dictionary) { if (!create.dictionary || !create.dictionary->source) return {}; /// Evaluate expressions (like currentDatabase() or tcpPort()) in dictionary source definition. NormalizeAndEvaluateConstantsVisitor::Data visitor_data{getContext()}; NormalizeAndEvaluateConstantsVisitor visitor(visitor_data); visitor.visit(create.dictionary->source->ptr()); return {}; } else if (!create.storage || !create.storage->engine) throw Exception(ErrorCodes::LOGICAL_ERROR, "Unexpected application state. CREATE query is missing either its storage or engine."); /// We can have queries like "CREATE TABLE ENGINE=" if /// supports schema inference (will determine table structure in it's constructor). else if (!StorageFactory::instance().checkIfStorageSupportsSchemaInterface(create.storage->engine->name)) throw Exception(ErrorCodes::INCORRECT_QUERY, "Incorrect CREATE query: required list of column descriptions or AS section or SELECT."); /// Even if query has list of columns, canonicalize it (unfold Nested columns). if (!create.columns_list) create.set(create.columns_list, std::make_shared()); ASTPtr new_columns = formatColumns(properties.columns); ASTPtr new_indices = formatIndices(properties.indices); ASTPtr new_constraints = formatConstraints(properties.constraints); ASTPtr new_projections = formatProjections(properties.projections); create.columns_list->setOrReplace(create.columns_list->columns, new_columns); create.columns_list->setOrReplace(create.columns_list->indices, new_indices); create.columns_list->setOrReplace(create.columns_list->constraints, new_constraints); create.columns_list->setOrReplace(create.columns_list->projections, new_projections); validateTableStructure(create, properties); assert(as_database_saved.empty() && as_table_saved.empty()); std::swap(create.as_database, as_database_saved); std::swap(create.as_table, as_table_saved); return properties; } void InterpreterCreateQuery::validateTableStructure(const ASTCreateQuery & create, const InterpreterCreateQuery::TableProperties & properties) const { /// Check for duplicates std::set all_columns; for (const auto & column : properties.columns) { if (!all_columns.emplace(column.name).second) throw Exception(ErrorCodes::DUPLICATE_COLUMN, "Column {} already exists", backQuoteIfNeed(column.name)); } /// Check if _row_exists for lightweight delete column in column_lists for merge tree family. if (create.storage && create.storage->engine && endsWith(create.storage->engine->name, "MergeTree")) { auto search = all_columns.find(LightweightDeleteDescription::FILTER_COLUMN.name); if (search != all_columns.end()) throw Exception(ErrorCodes::ILLEGAL_COLUMN, "Cannot create table with column '{}' for *MergeTree engines because it " "is reserved for lightweight delete feature", LightweightDeleteDescription::FILTER_COLUMN.name); } const auto & settings = getContext()->getSettingsRef(); /// Check low cardinality types in creating table if it was not allowed in setting if (!create.attach && !settings.allow_suspicious_low_cardinality_types && !create.is_materialized_view) { for (const auto & name_and_type_pair : properties.columns.getAllPhysical()) { if (const auto * current_type_ptr = typeid_cast(name_and_type_pair.type.get())) { if (!isStringOrFixedString(*removeNullable(current_type_ptr->getDictionaryType()))) throw Exception(ErrorCodes::SUSPICIOUS_TYPE_FOR_LOW_CARDINALITY, "Creating columns of type {} is prohibited by default " "due to expected negative impact on performance. " "It can be enabled with the \"allow_suspicious_low_cardinality_types\" setting.", current_type_ptr->getName()); } } } if (!create.attach && !settings.allow_experimental_object_type) { for (const auto & [name, type] : properties.columns.getAllPhysical()) { if (type->hasDynamicSubcolumns()) { throw Exception(ErrorCodes::ILLEGAL_COLUMN, "Cannot create table with column '{}' which type is '{}' " "because experimental Object type is not allowed. " "Set setting allow_experimental_object_type = 1 in order to allow it", name, type->getName()); } } } if (!create.attach && !settings.allow_suspicious_fixed_string_types) { for (const auto & [name, type] : properties.columns.getAllPhysical()) { auto basic_type = removeLowCardinality(removeNullable(type)); if (const auto * fixed_string = typeid_cast(basic_type.get())) { if (fixed_string->getN() > MAX_FIXEDSTRING_SIZE_WITHOUT_SUSPICIOUS) throw Exception(ErrorCodes::ILLEGAL_COLUMN, "Cannot create table with column '{}' which type is '{}' " "because fixed string with size > {} is suspicious. " "Set setting allow_suspicious_fixed_string_types = 1 in order to allow it", name, type->getName(), MAX_FIXEDSTRING_SIZE_WITHOUT_SUSPICIOUS); } } } } String InterpreterCreateQuery::getTableEngineName(DefaultTableEngine default_table_engine) { switch (default_table_engine) { case DefaultTableEngine::Log: return "Log"; case DefaultTableEngine::StripeLog: return "StripeLog"; case DefaultTableEngine::MergeTree: return "MergeTree"; case DefaultTableEngine::ReplacingMergeTree: return "ReplacingMergeTree"; case DefaultTableEngine::ReplicatedMergeTree: return "ReplicatedMergeTree"; case DefaultTableEngine::ReplicatedReplacingMergeTree: return "ReplicatedReplacingMergeTree"; case DefaultTableEngine::Memory: return "Memory"; default: throw Exception(ErrorCodes::LOGICAL_ERROR, "default_table_engine is set to unknown value"); } } void InterpreterCreateQuery::setDefaultTableEngine(ASTStorage & storage, DefaultTableEngine engine) { if (engine == DefaultTableEngine::None) throw Exception(ErrorCodes::ENGINE_REQUIRED, "Table engine is not specified in CREATE query"); auto engine_ast = std::make_shared(); engine_ast->name = getTableEngineName(engine); engine_ast->no_empty_args = true; storage.set(storage.engine, engine_ast); } void InterpreterCreateQuery::setEngine(ASTCreateQuery & create) const { if (create.as_table_function) return; if (create.is_dictionary || create.is_ordinary_view || create.is_live_view || create.is_window_view) return; if (create.is_materialized_view && create.to_table_id) return; if (create.temporary) { /// It's possible if some part of storage definition (such as PARTITION BY) is specified, but ENGINE is not. /// It makes sense when default_table_engine setting is used, but not for temporary tables. /// For temporary tables we ignore this setting to allow CREATE TEMPORARY TABLE query without specifying ENGINE if (!create.cluster.empty()) throw Exception(ErrorCodes::INCORRECT_QUERY, "Temporary tables cannot be created with ON CLUSTER clause"); if (create.storage && create.storage->engine) { if (create.storage->engine->name.starts_with("Replicated") || create.storage->engine->name == "KeeperMap") throw Exception(ErrorCodes::INCORRECT_QUERY, "Temporary tables cannot be created with Replicated or KeeperMap table engines"); return; } else { if (!create.storage) { auto storage_ast = std::make_shared(); create.set(create.storage, storage_ast); } setDefaultTableEngine(*create.storage, getContext()->getSettingsRef().default_temporary_table_engine.value); } return; } if (create.storage) { /// Some part of storage definition (such as PARTITION BY) is specified, but ENGINE is not: just set default one. if (!create.storage->engine) setDefaultTableEngine(*create.storage, getContext()->getSettingsRef().default_table_engine.value); return; } if (!create.as_table.empty()) { /// NOTE Getting the structure from the table specified in the AS is done not atomically with the creation of the table. String as_database_name = getContext()->resolveDatabase(create.as_database); String as_table_name = create.as_table; ASTPtr as_create_ptr = DatabaseCatalog::instance().getDatabase(as_database_name)->getCreateTableQuery(as_table_name, getContext()); const auto & as_create = as_create_ptr->as(); const String qualified_name = backQuoteIfNeed(as_database_name) + "." + backQuoteIfNeed(as_table_name); if (as_create.is_ordinary_view) throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot CREATE a table AS {}, it is a View", qualified_name); if (as_create.is_live_view) throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot CREATE a table AS {}, it is a Live View", qualified_name); if (as_create.is_window_view) throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot CREATE a table AS {}, it is a Window View", qualified_name); if (as_create.is_dictionary) throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot CREATE a table AS {}, it is a Dictionary", qualified_name); if (as_create.storage) create.set(create.storage, as_create.storage->ptr()); else if (as_create.as_table_function) create.set(create.as_table_function, as_create.as_table_function->ptr()); else throw Exception(ErrorCodes::LOGICAL_ERROR, "Cannot set engine, it's a bug."); return; } create.set(create.storage, std::make_shared()); setDefaultTableEngine(*create.storage, getContext()->getSettingsRef().default_table_engine.value); } static void generateUUIDForTable(ASTCreateQuery & create) { if (create.uuid == UUIDHelpers::Nil) create.uuid = UUIDHelpers::generateV4(); /// If destination table (to_table_id) is not specified for materialized view, /// then MV will create inner table. We should generate UUID of inner table here, /// so it will be the same on all hosts if query in ON CLUSTER or database engine is Replicated. bool need_uuid_for_inner_table = !create.attach && create.is_materialized_view && !create.to_table_id; if (need_uuid_for_inner_table && create.to_inner_uuid == UUIDHelpers::Nil) create.to_inner_uuid = UUIDHelpers::generateV4(); } void InterpreterCreateQuery::assertOrSetUUID(ASTCreateQuery & create, const DatabasePtr & database) const { const auto * kind = create.is_dictionary ? "Dictionary" : "Table"; const auto * kind_upper = create.is_dictionary ? "DICTIONARY" : "TABLE"; if (database->getEngineName() == "Replicated" && getContext()->getClientInfo().is_replicated_database_internal && !internal) { if (create.uuid == UUIDHelpers::Nil) throw Exception(ErrorCodes::LOGICAL_ERROR, "Table UUID is not specified in DDL log"); } bool from_path = create.attach_from_path.has_value(); if (database->getUUID() != UUIDHelpers::Nil) { if (create.attach && !from_path && create.uuid == UUIDHelpers::Nil) { throw Exception(ErrorCodes::INCORRECT_QUERY, "Incorrect ATTACH {} query for Atomic database engine. " "Use one of the following queries instead:\n" "1. ATTACH {} {};\n" "2. CREATE {} {}
;\n" "3. ATTACH {} {} FROM '/path/to/data/'
;\n" "4. ATTACH {} {} UUID ''
;", kind_upper, kind_upper, create.table, kind_upper, create.table, kind_upper, create.table, kind_upper, create.table); } generateUUIDForTable(create); } else { bool is_on_cluster = getContext()->getClientInfo().query_kind == ClientInfo::QueryKind::SECONDARY_QUERY; bool has_uuid = create.uuid != UUIDHelpers::Nil || create.to_inner_uuid != UUIDHelpers::Nil; if (has_uuid && !is_on_cluster) throw Exception(ErrorCodes::INCORRECT_QUERY, "{} UUID specified, but engine of database {} is not Atomic", kind, create.getDatabase()); /// Ignore UUID if it's ON CLUSTER query create.uuid = UUIDHelpers::Nil; create.to_inner_uuid = UUIDHelpers::Nil; } } BlockIO InterpreterCreateQuery::createTable(ASTCreateQuery & create) { /// Temporary tables are created out of databases. if (create.temporary && create.database) throw Exception(ErrorCodes::BAD_DATABASE_FOR_TEMPORARY_TABLE, "Temporary tables cannot be inside a database. " "You should not specify a database for a temporary table."); String current_database = getContext()->getCurrentDatabase(); auto database_name = create.database ? create.getDatabase() : current_database; DDLGuardPtr ddl_guard; // If this is a stub ATTACH query, read the query definition from the database if (create.attach && !create.storage && !create.columns_list) { auto database = DatabaseCatalog::instance().getDatabase(database_name); if (database->shouldReplicateQuery(getContext(), query_ptr)) { auto guard = DatabaseCatalog::instance().getDDLGuard(database_name, create.getTable()); create.setDatabase(database_name); guard->releaseTableLock(); return database->tryEnqueueReplicatedDDL(query_ptr, getContext(), internal); } if (!create.cluster.empty()) return executeQueryOnCluster(create); /// For short syntax of ATTACH query we have to lock table name here, before reading metadata /// and hold it until table is attached if (likely(need_ddl_guard)) ddl_guard = DatabaseCatalog::instance().getDDLGuard(database_name, create.getTable()); bool if_not_exists = create.if_not_exists; // Table SQL definition is available even if the table is detached (even permanently) auto query = database->getCreateTableQuery(create.getTable(), getContext()); auto create_query = query->as(); if (!create.is_dictionary && create_query.is_dictionary) throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot ATTACH TABLE {}.{}, it is a Dictionary", backQuoteIfNeed(database_name), backQuoteIfNeed(create.getTable())); if (create.is_dictionary && !create_query.is_dictionary) throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot ATTACH DICTIONARY {}.{}, it is a Table", backQuoteIfNeed(database_name), backQuoteIfNeed(create.getTable())); create = create_query; // Copy the saved create query, but use ATTACH instead of CREATE create.attach = true; create.attach_short_syntax = true; create.if_not_exists = if_not_exists; /// Compatibility setting which should be enabled by default on attach /// Otherwise server will be unable to start for some old-format of IPv6/IPv4 types getContext()->setSetting("cast_ipv4_ipv6_default_on_conversion_error", 1); } /// TODO throw exception if !create.attach_short_syntax && !create.attach_from_path && !internal if (create.attach_from_path) { chassert(!ddl_guard); fs::path user_files = fs::path(getContext()->getUserFilesPath()).lexically_normal(); fs::path root_path = fs::path(getContext()->getPath()).lexically_normal(); if (getContext()->getClientInfo().query_kind == ClientInfo::QueryKind::INITIAL_QUERY) { fs::path data_path = fs::path(*create.attach_from_path).lexically_normal(); if (data_path.is_relative()) data_path = (user_files / data_path).lexically_normal(); if (!startsWith(data_path, user_files)) throw Exception(ErrorCodes::PATH_ACCESS_DENIED, "Data directory {} must be inside {} to attach it", String(data_path), String(user_files)); /// Data path must be relative to root_path create.attach_from_path = fs::relative(data_path, root_path) / ""; } else { fs::path data_path = (root_path / *create.attach_from_path).lexically_normal(); if (!startsWith(data_path, user_files)) throw Exception(ErrorCodes::PATH_ACCESS_DENIED, "Data directory {} must be inside {} to attach it", String(data_path), String(user_files)); } } else if (create.attach && !create.attach_short_syntax && getContext()->getClientInfo().query_kind != ClientInfo::QueryKind::SECONDARY_QUERY) { auto * log = &Poco::Logger::get("InterpreterCreateQuery"); LOG_WARNING(log, "ATTACH TABLE query with full table definition is not recommended: " "use either ATTACH TABLE {}; to attach existing table " "or CREATE TABLE {}
; to create new table " "or ATTACH TABLE {} FROM '/path/to/data/'
; to create new table and attach data.", create.getTable(), create.getTable(), create.getTable()); } if (!create.temporary && !create.database) create.setDatabase(current_database); if (create.to_table_id && create.to_table_id.database_name.empty()) create.to_table_id.database_name = current_database; if (create.select && create.isView()) { // Expand CTE before filling default database ApplyWithSubqueryVisitor().visit(*create.select); AddDefaultDatabaseVisitor visitor(getContext(), current_database); visitor.visit(*create.select); } if (create.columns_list) { AddDefaultDatabaseVisitor visitor(getContext(), current_database); visitor.visit(*create.columns_list); } // substitute possible UDFs with their definitions if (!UserDefinedSQLFunctionFactory::instance().empty()) UserDefinedSQLFunctionVisitor::visit(query_ptr); /// Set and retrieve list of columns, indices and constraints. Set table engine if needed. Rewrite query in canonical way. TableProperties properties = getTablePropertiesAndNormalizeCreateQuery(create); /// Check type compatible for materialized dest table and select columns if (create.select && create.is_materialized_view && create.to_table_id && !create.attach) { if (StoragePtr to_table = DatabaseCatalog::instance().tryGetTable( {create.to_table_id.database_name, create.to_table_id.table_name, create.to_table_id.uuid}, getContext() )) { Block input_block; if (getContext()->getSettingsRef().allow_experimental_analyzer) { input_block = InterpreterSelectQueryAnalyzer::getSampleBlock(create.select->clone(), getContext()); } else { input_block = InterpreterSelectWithUnionQuery(create.select->clone(), getContext(), SelectQueryOptions().analyze()).getSampleBlock(); } Block output_block = to_table->getInMemoryMetadataPtr()->getSampleBlock(); ColumnsWithTypeAndName input_columns; ColumnsWithTypeAndName output_columns; for (const auto & input_column : input_block) { if (const auto * output_column = output_block.findByName(input_column.name)) { input_columns.push_back(input_column.cloneEmpty()); output_columns.push_back(output_column->cloneEmpty()); } } ActionsDAG::makeConvertingActions( input_columns, output_columns, ActionsDAG::MatchColumnsMode::Position ); } } DatabasePtr database; bool need_add_to_database = !create.temporary; if (need_add_to_database) database = DatabaseCatalog::instance().getDatabase(database_name); if (need_add_to_database && database->shouldReplicateQuery(getContext(), query_ptr)) { chassert(!ddl_guard); auto guard = DatabaseCatalog::instance().getDDLGuard(create.getDatabase(), create.getTable()); assertOrSetUUID(create, database); guard->releaseTableLock(); return database->tryEnqueueReplicatedDDL(query_ptr, getContext(), internal); } if (!create.cluster.empty()) { chassert(!ddl_guard); return executeQueryOnCluster(create); } if (create.replace_table) { chassert(!ddl_guard); return doCreateOrReplaceTable(create, properties); } /// Actually creates table bool created = doCreateTable(create, properties, ddl_guard); ddl_guard.reset(); if (!created) /// Table already exists return {}; /// If table has dependencies - add them to the graph QualifiedTableName qualified_name{database_name, create.getTable()}; auto ref_dependencies = getDependenciesFromCreateQuery(getContext()->getGlobalContext(), qualified_name, query_ptr); auto loading_dependencies = getLoadingDependenciesFromCreateQuery(getContext()->getGlobalContext(), qualified_name, query_ptr); DatabaseCatalog::instance().addDependencies(qualified_name, ref_dependencies, loading_dependencies); return fillTableIfNeeded(create); } bool InterpreterCreateQuery::doCreateTable(ASTCreateQuery & create, const InterpreterCreateQuery::TableProperties & properties, DDLGuardPtr & ddl_guard) { if (create.temporary) { if (create.if_not_exists && getContext()->tryResolveStorageID({"", create.getTable()}, Context::ResolveExternal)) return false; DatabasePtr database = DatabaseCatalog::instance().getDatabase(DatabaseCatalog::TEMPORARY_DATABASE); String temporary_table_name = create.getTable(); auto creator = [&](const StorageID & table_id) { return StorageFactory::instance().get(create, database->getTableDataPath(table_id.getTableName()), getContext(), getContext()->getGlobalContext(), properties.columns, properties.constraints, false); }; auto temporary_table = TemporaryTableHolder(getContext(), creator, query_ptr); getContext()->getSessionContext()->addExternalTable(temporary_table_name, std::move(temporary_table)); return true; } if (!ddl_guard && likely(need_ddl_guard)) ddl_guard = DatabaseCatalog::instance().getDDLGuard(create.getDatabase(), create.getTable()); String data_path; DatabasePtr database; database = DatabaseCatalog::instance().getDatabase(create.getDatabase()); assertOrSetUUID(create, database); String storage_name = create.is_dictionary ? "Dictionary" : "Table"; auto storage_already_exists_error_code = create.is_dictionary ? ErrorCodes::DICTIONARY_ALREADY_EXISTS : ErrorCodes::TABLE_ALREADY_EXISTS; /// Table can be created before or it can be created concurrently in another thread, while we were waiting in DDLGuard. if (database->isTableExist(create.getTable(), getContext())) { /// TODO Check structure of table if (create.if_not_exists) return false; else if (create.replace_view) { /// when executing CREATE OR REPLACE VIEW, drop current existing view auto drop_ast = std::make_shared(); drop_ast->setDatabase(create.getDatabase()); drop_ast->setTable(create.getTable()); drop_ast->no_ddl_lock = true; auto drop_context = Context::createCopy(context); InterpreterDropQuery interpreter(drop_ast, drop_context); interpreter.execute(); } else throw Exception(storage_already_exists_error_code, "{} {}.{} already exists", storage_name, backQuoteIfNeed(create.getDatabase()), backQuoteIfNeed(create.getTable())); } else if (!create.attach) { /// Checking that table may exists in detached/detached permanently state try { database->checkMetadataFilenameAvailability(create.getTable()); } catch (const Exception &) { if (create.if_not_exists) return false; throw; } } data_path = database->getTableDataPath(create); if (!create.attach && !data_path.empty() && fs::exists(fs::path{getContext()->getPath()} / data_path)) throw Exception(storage_already_exists_error_code, "Directory for {} data {} already exists", Poco::toLower(storage_name), String(data_path)); bool from_path = create.attach_from_path.has_value(); String actual_data_path = data_path; if (from_path) { if (data_path.empty()) throw Exception(ErrorCodes::NOT_IMPLEMENTED, "ATTACH ... FROM ... query is not supported for {} database engine", database->getEngineName()); /// We will try to create Storage instance with provided data path data_path = *create.attach_from_path; create.attach_from_path = std::nullopt; } if (create.attach) { /// If table was detached it's not possible to attach it back while some threads are using /// old instance of the storage. For example, AsynchronousMetrics may cause ATTACH to fail, /// so we allow waiting here. If database_atomic_wait_for_drop_and_detach_synchronously is disabled /// and old storage instance still exists it will throw exception. if (getContext()->getSettingsRef().database_atomic_wait_for_drop_and_detach_synchronously) database->waitDetachedTableNotInUse(create.uuid); else database->checkDetachedTableNotInUse(create.uuid); } /// We should lock UUID on CREATE query (because for ATTACH it must be already locked previously). /// But ATTACH without create.attach_short_syntax flag works like CREATE actually, that's why we check it. bool need_lock_uuid = !create.attach_short_syntax; TemporaryLockForUUIDDirectory uuid_lock; if (need_lock_uuid) uuid_lock = TemporaryLockForUUIDDirectory{create.uuid}; else if (create.uuid != UUIDHelpers::Nil && !DatabaseCatalog::instance().hasUUIDMapping(create.uuid)) { /// FIXME MaterializedPostgreSQL works with UUIDs incorrectly and breaks invariants if (database->getEngineName() != "MaterializedPostgreSQL") throw Exception(ErrorCodes::LOGICAL_ERROR, "Cannot find UUID mapping for {}, it's a bug", create.uuid); } StoragePtr res; /// NOTE: CREATE query may be rewritten by Storage creator or table function if (create.as_table_function) { auto table_function_ast = create.as_table_function->ptr(); auto table_function = TableFunctionFactory::instance().get(table_function_ast, getContext()); /// In case of CREATE AS table_function() query we should use global context /// in storage creation because there will be no query context on server startup /// and because storage lifetime is bigger than query context lifetime. res = table_function->execute(table_function_ast, getContext(), create.getTable(), properties.columns, /*use_global_context=*/true); res->renameInMemory({create.getDatabase(), create.getTable(), create.uuid}); } else { res = StorageFactory::instance().get(create, data_path, getContext(), getContext()->getGlobalContext(), properties.columns, properties.constraints, false); /// If schema wes inferred while storage creation, add columns description to create query. addColumnsDescriptionToCreateQueryIfNecessary(query_ptr->as(), res); } if (!create.attach && getContext()->getSettingsRef().database_replicated_allow_only_replicated_engine) { bool is_replicated_storage = typeid_cast(res.get()) != nullptr; if (!is_replicated_storage && res->storesDataOnDisk() && database && database->getEngineName() == "Replicated") throw Exception(ErrorCodes::UNKNOWN_STORAGE, "Only tables with a Replicated engine " "or tables which do not store data on disk are allowed in a Replicated database"); } if (from_path && !res->storesDataOnDisk()) throw Exception(ErrorCodes::NOT_IMPLEMENTED, "ATTACH ... FROM ... query is not supported for {} table engine, " "because such tables do not store any data on disk. Use CREATE instead.", res->getName()); database->createTable(getContext(), create.getTable(), res, query_ptr); /// Move table data to the proper place. Wo do not move data earlier to avoid situations /// when data directory moved, but table has not been created due to some error. if (from_path) res->rename(actual_data_path, {create.getDatabase(), create.getTable(), create.uuid}); /// We must call "startup" and "shutdown" while holding DDLGuard. /// Because otherwise method "shutdown" (from InterpreterDropQuery) can be called before startup /// (in case when table was created and instantly dropped before started up) /// /// Method "startup" may create background tasks and method "shutdown" will wait for them. /// But if "shutdown" is called before "startup", it will exit early, because there are no background tasks to wait. /// Then background task is created by "startup" method. And when destructor of a table object is called, background task is still active, /// and the task will use references to freed data. /// Also note that "startup" method is exception-safe. If exception is thrown from "startup", /// we can safely destroy the object without a call to "shutdown", because there is guarantee /// that no background threads/similar resources remain after exception from "startup". if (!res->supportsDynamicSubcolumns() && hasDynamicSubcolumns(res->getInMemoryMetadataPtr()->getColumns())) { throw Exception(ErrorCodes::ILLEGAL_COLUMN, "Cannot create table with column of type Object, " "because storage {} doesn't support dynamic subcolumns", res->getName()); } res->startup(); return true; } BlockIO InterpreterCreateQuery::doCreateOrReplaceTable(ASTCreateQuery & create, const InterpreterCreateQuery::TableProperties & properties) { /// Replicated database requires separate contexts for each DDL query ContextPtr current_context = getContext(); if (auto txn = current_context->getZooKeeperMetadataTransaction()) txn->setIsCreateOrReplaceQuery(); ContextMutablePtr create_context = Context::createCopy(current_context); create_context->setQueryContext(std::const_pointer_cast(current_context)); auto make_drop_context = [&]() -> ContextMutablePtr { ContextMutablePtr drop_context = Context::createCopy(current_context); drop_context->setQueryContext(std::const_pointer_cast(current_context)); return drop_context; }; auto ast_drop = std::make_shared(); String table_to_replace_name = create.getTable(); { auto database = DatabaseCatalog::instance().getDatabase(create.getDatabase()); if (database->getUUID() == UUIDHelpers::Nil) throw Exception(ErrorCodes::INCORRECT_QUERY, "{} query is supported only for Atomic databases", create.create_or_replace ? "CREATE OR REPLACE TABLE" : "REPLACE TABLE"); UInt64 name_hash = sipHash64(create.getDatabase() + create.getTable()); UInt16 random_suffix = thread_local_rng(); if (auto txn = current_context->getZooKeeperMetadataTransaction()) { /// Avoid different table name on database replicas random_suffix = sipHash64(txn->getTaskZooKeeperPath()); } create.setTable(fmt::format("_tmp_replace_{}_{}", getHexUIntLowercase(name_hash), getHexUIntLowercase(random_suffix))); ast_drop->setTable(create.getTable()); ast_drop->is_dictionary = create.is_dictionary; ast_drop->setDatabase(create.getDatabase()); ast_drop->kind = ASTDropQuery::Drop; } bool created = false; bool renamed = false; try { /// Create temporary table (random name will be generated) DDLGuardPtr ddl_guard; [[maybe_unused]] bool done = InterpreterCreateQuery(query_ptr, create_context).doCreateTable(create, properties, ddl_guard); ddl_guard.reset(); assert(done); created = true; /// Try fill temporary table BlockIO fill_io = fillTableIfNeeded(create); executeTrivialBlockIO(fill_io, getContext()); /// Replace target table with created one auto ast_rename = std::make_shared(); ASTRenameQuery::Element elem { ASTRenameQuery::Table { create.getDatabase().empty() ? nullptr : std::make_shared(create.getDatabase()), std::make_shared(create.getTable()) }, ASTRenameQuery::Table { create.getDatabase().empty() ? nullptr : std::make_shared(create.getDatabase()), std::make_shared(table_to_replace_name) } }; ast_rename->elements.push_back(std::move(elem)); ast_rename->dictionary = create.is_dictionary; if (create.create_or_replace) { /// CREATE OR REPLACE TABLE /// Will execute ordinary RENAME instead of EXCHANGE if the target table does not exist ast_rename->rename_if_cannot_exchange = true; ast_rename->exchange = false; } else { /// REPLACE TABLE /// Will execute EXCHANGE query and fail if the target table does not exist ast_rename->exchange = true; } InterpreterRenameQuery interpreter_rename{ast_rename, current_context}; interpreter_rename.execute(); renamed = true; if (!interpreter_rename.renamedInsteadOfExchange()) { /// Target table was replaced with new one, drop old table auto drop_context = make_drop_context(); InterpreterDropQuery(ast_drop, drop_context).execute(); } create.setTable(table_to_replace_name); return {}; } catch (...) { /// Drop temporary table if it was successfully created, but was not renamed to target name if (created && !renamed) { auto drop_context = make_drop_context(); InterpreterDropQuery(ast_drop, drop_context).execute(); } throw; } } BlockIO InterpreterCreateQuery::fillTableIfNeeded(const ASTCreateQuery & create) { /// If the query is a CREATE SELECT, insert the data into the table. if (create.select && !create.attach && !create.is_create_empty && !create.is_ordinary_view && !create.is_live_view && (!(create.is_materialized_view || create.is_window_view) || create.is_populate)) { auto insert = std::make_shared(); insert->table_id = {create.getDatabase(), create.getTable(), create.uuid}; if (create.is_window_view) { auto table = DatabaseCatalog::instance().getTable(insert->table_id, getContext()); insert->select = typeid_cast(table.get())->getSourceTableSelectQuery(); } else insert->select = create.select->clone(); return InterpreterInsertQuery(insert, getContext(), getContext()->getSettingsRef().insert_allow_materialized_columns).execute(); } return {}; } void InterpreterCreateQuery::prepareOnClusterQuery(ASTCreateQuery & create, ContextPtr local_context, const String & cluster_name) { if (create.attach) return; /// For CREATE query generate UUID on initiator, so it will be the same on all hosts. /// It will be ignored if database does not support UUIDs. generateUUIDForTable(create); /// For cross-replication cluster we cannot use UUID in replica path. String cluster_name_expanded = local_context->getMacros()->expand(cluster_name); ClusterPtr cluster = local_context->getCluster(cluster_name_expanded); if (cluster->maybeCrossReplication()) { auto on_cluster_version = local_context->getSettingsRef().distributed_ddl_entry_format_version; if (DDLLogEntry::NORMALIZE_CREATE_ON_INITIATOR_VERSION <= on_cluster_version) throw Exception(ErrorCodes::NOT_IMPLEMENTED, "Value {} of setting distributed_ddl_entry_format_version " "is incompatible with cross-replication", on_cluster_version); /// Check that {uuid} macro is not used in zookeeper_path for ReplicatedMergeTree. /// Otherwise replicas will generate different paths. if (!create.storage) return; if (!create.storage->engine) return; if (!startsWith(create.storage->engine->name, "Replicated")) return; bool has_explicit_zk_path_arg = create.storage->engine->arguments && create.storage->engine->arguments->children.size() >= 2 && create.storage->engine->arguments->children[0]->as() && create.storage->engine->arguments->children[0]->as()->value.getType() == Field::Types::String; if (has_explicit_zk_path_arg) { String zk_path = create.storage->engine->arguments->children[0]->as()->value.get(); Macros::MacroExpansionInfo info; info.table_id.uuid = create.uuid; info.ignore_unknown = true; local_context->getMacros()->expand(zk_path, info); if (!info.expanded_uuid) return; } throw Exception(ErrorCodes::INCORRECT_QUERY, "Seems like cluster is configured for cross-replication, " "but zookeeper_path for ReplicatedMergeTree is not specified or contains {uuid} macro. " "It's not supported for cross replication, because tables must have different UUIDs. " "Please specify unique zookeeper_path explicitly."); } } BlockIO InterpreterCreateQuery::executeQueryOnCluster(ASTCreateQuery & create) { prepareOnClusterQuery(create, getContext(), create.cluster); DDLQueryOnClusterParams params; params.access_to_check = getRequiredAccess(); return executeDDLQueryOnCluster(query_ptr, getContext(), params); } BlockIO InterpreterCreateQuery::execute() { FunctionNameNormalizer().visit(query_ptr.get()); auto & create = query_ptr->as(); bool is_create_database = create.database && !create.table; if (!create.cluster.empty() && !maybeRemoveOnCluster(query_ptr, getContext())) { auto on_cluster_version = getContext()->getSettingsRef().distributed_ddl_entry_format_version; if (is_create_database || on_cluster_version < DDLLogEntry::NORMALIZE_CREATE_ON_INITIATOR_VERSION) return executeQueryOnCluster(create); } getContext()->checkAccess(getRequiredAccess()); ASTQueryWithOutput::resetOutputASTIfExist(create); /// CREATE|ATTACH DATABASE if (is_create_database) return createDatabase(create); else return createTable(create); } AccessRightsElements InterpreterCreateQuery::getRequiredAccess() const { /// Internal queries (initiated by the server itself) always have access to everything. if (internal) return {}; AccessRightsElements required_access; const auto & create = query_ptr->as(); if (!create.table) { required_access.emplace_back(AccessType::CREATE_DATABASE, create.getDatabase()); } else if (create.is_dictionary) { required_access.emplace_back(AccessType::CREATE_DICTIONARY, create.getDatabase(), create.getTable()); } else if (create.isView()) { assert(!create.temporary); if (create.replace_view) required_access.emplace_back(AccessType::DROP_VIEW | AccessType::CREATE_VIEW, create.getDatabase(), create.getTable()); else required_access.emplace_back(AccessType::CREATE_VIEW, create.getDatabase(), create.getTable()); } else { if (create.temporary) { /// Currently default table engine for temporary tables is Memory. default_table_engine does not affect temporary tables. if (create.storage && create.storage->engine && create.storage->engine->name != "Memory") required_access.emplace_back(AccessType::CREATE_ARBITRARY_TEMPORARY_TABLE); else required_access.emplace_back(AccessType::CREATE_TEMPORARY_TABLE); } else { if (create.replace_table) required_access.emplace_back(AccessType::DROP_TABLE, create.getDatabase(), create.getTable()); required_access.emplace_back(AccessType::CREATE_TABLE, create.getDatabase(), create.getTable()); } } if (create.to_table_id) required_access.emplace_back(AccessType::SELECT | AccessType::INSERT, create.to_table_id.database_name, create.to_table_id.table_name); if (create.storage && create.storage->engine) { auto source_access_type = StorageFactory::instance().getSourceAccessType(create.storage->engine->name); if (source_access_type != AccessType::NONE) required_access.emplace_back(source_access_type); } return required_access; } void InterpreterCreateQuery::extendQueryLogElemImpl(QueryLogElement & elem, const ASTPtr &, ContextPtr) const { if (!as_table_saved.empty()) { String database = backQuoteIfNeed(as_database_saved.empty() ? getContext()->getCurrentDatabase() : as_database_saved); elem.query_databases.insert(database); elem.query_tables.insert(database + "." + backQuoteIfNeed(as_table_saved)); } } void InterpreterCreateQuery::addColumnsDescriptionToCreateQueryIfNecessary(ASTCreateQuery & create, const StoragePtr & storage) { if (create.is_dictionary || (create.columns_list && create.columns_list->columns && !create.columns_list->columns->children.empty())) return; auto ast_storage = std::make_shared(); unsigned max_parser_depth = static_cast(getContext()->getSettingsRef().max_parser_depth); auto query_from_storage = DB::getCreateQueryFromStorage(storage, ast_storage, false, max_parser_depth, true); auto & create_query_from_storage = query_from_storage->as(); if (!create.columns_list) { ASTPtr columns_list = std::make_shared(*create_query_from_storage.columns_list); create.set(create.columns_list, columns_list); } else { ASTPtr columns = std::make_shared(*create_query_from_storage.columns_list->columns); create.columns_list->set(create.columns_list->columns, columns); } } }