#include #include #include #include #include #include #include #include #include #include #include #include #include #include #if !defined(ARCADIA_BUILD) # include "config_core.h" #endif #if USE_MYSQL # include #endif namespace DB { namespace ErrorCodes { extern const int LOGICAL_ERROR; extern const int SYNTAX_ERROR; extern const int UNKNOWN_TABLE; extern const int UNKNOWN_DICTIONARY; extern const int NOT_IMPLEMENTED; extern const int INCORRECT_QUERY; } static DatabasePtr tryGetDatabase(const String & database_name, bool if_exists) { return if_exists ? DatabaseCatalog::instance().tryGetDatabase(database_name) : DatabaseCatalog::instance().getDatabase(database_name); } InterpreterDropQuery::InterpreterDropQuery(const ASTPtr & query_ptr_, Context & context_) : query_ptr(query_ptr_), context(context_) {} BlockIO InterpreterDropQuery::execute() { auto & drop = query_ptr->as(); if (!drop.cluster.empty()) return executeDDLQueryOnCluster(query_ptr, context, getRequiredAccessForDDLOnCluster()); if (context.getSettingsRef().database_atomic_wait_for_drop_and_detach_synchronously) drop.no_delay = true; if (!drop.table.empty()) { if (!drop.is_dictionary) return executeToTable(drop); else if (drop.permanently && drop.kind == ASTDropQuery::Kind::Detach) throw Exception("DETACH PERMANENTLY is not implemented for dictionaries", ErrorCodes::NOT_IMPLEMENTED); else return executeToDictionary(drop.database, drop.table, drop.kind, drop.if_exists, drop.temporary, drop.no_ddl_lock); } else if (!drop.database.empty()) return executeToDatabase(drop); else throw Exception("Nothing to drop, both names are empty", ErrorCodes::LOGICAL_ERROR); } void InterpreterDropQuery::waitForTableToBeActuallyDroppedOrDetached(const ASTDropQuery & query, const DatabasePtr & db, const UUID & uuid_to_wait) { if (uuid_to_wait == UUIDHelpers::Nil) return; if (query.kind == ASTDropQuery::Kind::Drop) DatabaseCatalog::instance().waitTableFinallyDropped(uuid_to_wait); else if (query.kind == ASTDropQuery::Kind::Detach) db->waitDetachedTableNotInUse(uuid_to_wait); } BlockIO InterpreterDropQuery::executeToTable(const ASTDropQuery & query) { DatabasePtr database; UUID table_to_wait_on = UUIDHelpers::Nil; auto res = executeToTableImpl(query, database, table_to_wait_on); if (query.no_delay) waitForTableToBeActuallyDroppedOrDetached(query, database, table_to_wait_on); return res; } BlockIO InterpreterDropQuery::executeToTableImpl(const ASTDropQuery & query, DatabasePtr & db, UUID & uuid_to_wait) { /// NOTE: it does not contain UUID, we will resolve it with locked DDLGuard auto table_id = StorageID(query); if (query.temporary || table_id.database_name.empty()) { if (context.tryResolveStorageID(table_id, Context::ResolveExternal)) return executeToTemporaryTable(table_id.getTableName(), query.kind); else table_id.database_name = context.getCurrentDatabase(); } if (query.temporary) { if (query.if_exists) return {}; throw Exception("Temporary table " + backQuoteIfNeed(table_id.table_name) + " doesn't exist", ErrorCodes::UNKNOWN_TABLE); } auto ddl_guard = (!query.no_ddl_lock ? DatabaseCatalog::instance().getDDLGuard(table_id.database_name, table_id.table_name) : nullptr); /// If table was already dropped by anyone, an exception will be thrown auto [database, table] = query.if_exists ? DatabaseCatalog::instance().tryGetDatabaseAndTable(table_id, context) : DatabaseCatalog::instance().getDatabaseAndTable(table_id, context); if (database && table) { if (query.as().is_view && !table->isView()) throw Exception("Table " + table_id.getNameForLogs() + " is not a View", ErrorCodes::LOGICAL_ERROR); /// Now get UUID, so we can wait for table data to be finally dropped table_id.uuid = database->tryGetTableUUID(table_id.table_name); /// Prevents recursive drop from drop database query. The original query must specify a table. bool is_drop_or_detach_database = query_ptr->as()->table.empty(); bool is_replicated_ddl_query = typeid_cast(database.get()) && context.getClientInfo().query_kind != ClientInfo::QueryKind::REPLICATED_LOG_QUERY && !is_drop_or_detach_database; if (is_replicated_ddl_query) { if (query.kind == ASTDropQuery::Kind::Detach && !query.permanently) throw Exception(ErrorCodes::INCORRECT_QUERY, "DETACH TABLE is not allowed for Replicated databases. " "Use DETACH TABLE PERMANENTLY or SYSTEM RESTART REPLICA"); ddl_guard.reset(); table.reset(); return typeid_cast(database.get())->propose(query.clone()); } if (query.kind == ASTDropQuery::Kind::Detach) { context.checkAccess(table->isView() ? AccessType::DROP_VIEW : AccessType::DROP_TABLE, table_id); table->checkTableCanBeDetached(); table->shutdown(); TableExclusiveLockHolder table_lock; if (database->getUUID() == UUIDHelpers::Nil) table_lock = table->lockExclusively(context.getCurrentQueryId(), context.getSettingsRef().lock_acquire_timeout); if (query.permanently) { /// Drop table from memory, don't touch data, metadata file renamed and will be skipped during server restart database->detachTablePermanently(table_id.table_name); } else { /// Drop table from memory, don't touch data and metadata database->detachTable(table_id.table_name); } } else if (query.kind == ASTDropQuery::Kind::Truncate) { context.checkAccess(AccessType::TRUNCATE, table_id); table->checkTableCanBeDropped(); auto table_lock = table->lockExclusively(context.getCurrentQueryId(), context.getSettingsRef().lock_acquire_timeout); auto metadata_snapshot = table->getInMemoryMetadataPtr(); /// Drop table data, don't touch metadata table->truncate(query_ptr, metadata_snapshot, context, table_lock); } else if (query.kind == ASTDropQuery::Kind::Drop) { context.checkAccess(table->isView() ? AccessType::DROP_VIEW : AccessType::DROP_TABLE, table_id); table->checkTableCanBeDropped(); table->shutdown(); TableExclusiveLockHolder table_lock; if (database->getUUID() == UUIDHelpers::Nil) table_lock = table->lockExclusively(context.getCurrentQueryId(), context.getSettingsRef().lock_acquire_timeout); database->dropTable(context, table_id.table_name, query.no_delay); } db = database; uuid_to_wait = table_id.uuid; } return {}; } BlockIO InterpreterDropQuery::executeToDictionary( const String & database_name_, const String & dictionary_name, ASTDropQuery::Kind kind, bool if_exists, bool is_temporary, bool no_ddl_lock) { if (is_temporary) throw Exception("Temporary dictionaries are not possible.", ErrorCodes::SYNTAX_ERROR); String database_name = context.resolveDatabase(database_name_); auto ddl_guard = (!no_ddl_lock ? DatabaseCatalog::instance().getDDLGuard(database_name, dictionary_name) : nullptr); DatabasePtr database = tryGetDatabase(database_name, if_exists); if (!database || !database->isDictionaryExist(dictionary_name)) { if (!if_exists) throw Exception( "Dictionary " + backQuoteIfNeed(database_name) + "." + backQuoteIfNeed(dictionary_name) + " doesn't exist.", ErrorCodes::UNKNOWN_DICTIONARY); else return {}; } if (kind == ASTDropQuery::Kind::Detach) { /// Drop dictionary from memory, don't touch data and metadata context.checkAccess(AccessType::DROP_DICTIONARY, database_name, dictionary_name); database->detachDictionary(dictionary_name); } else if (kind == ASTDropQuery::Kind::Truncate) { throw Exception("Cannot TRUNCATE dictionary", ErrorCodes::SYNTAX_ERROR); } else if (kind == ASTDropQuery::Kind::Drop) { context.checkAccess(AccessType::DROP_DICTIONARY, database_name, dictionary_name); database->removeDictionary(context, dictionary_name); } return {}; } BlockIO InterpreterDropQuery::executeToTemporaryTable(const String & table_name, ASTDropQuery::Kind kind) { if (kind == ASTDropQuery::Kind::Detach) throw Exception("Unable to detach temporary table.", ErrorCodes::SYNTAX_ERROR); else { auto & context_handle = context.hasSessionContext() ? context.getSessionContext() : context; auto resolved_id = context_handle.tryResolveStorageID(StorageID("", table_name), Context::ResolveExternal); if (resolved_id) { StoragePtr table = DatabaseCatalog::instance().getTable(resolved_id, context); if (kind == ASTDropQuery::Kind::Truncate) { auto table_lock = table->lockExclusively(context.getCurrentQueryId(), context.getSettingsRef().lock_acquire_timeout); /// Drop table data, don't touch metadata auto metadata_snapshot = table->getInMemoryMetadataPtr(); table->truncate(query_ptr, metadata_snapshot, context, table_lock); } else if (kind == ASTDropQuery::Kind::Drop) { context_handle.removeExternalTable(table_name); table->shutdown(); auto table_lock = table->lockExclusively(context.getCurrentQueryId(), context.getSettingsRef().lock_acquire_timeout); /// Delete table data table->drop(); table->is_dropped = true; } } } return {}; } BlockIO InterpreterDropQuery::executeToDatabase(const ASTDropQuery & query) { DatabasePtr database; std::vector tables_to_wait; BlockIO res; try { res = executeToDatabaseImpl(query, database, tables_to_wait); } catch (...) { if (query.no_delay) { for (const auto & table_uuid : tables_to_wait) waitForTableToBeActuallyDroppedOrDetached(query, database, table_uuid); } throw; } if (query.no_delay) { for (const auto & table_uuid : tables_to_wait) waitForTableToBeActuallyDroppedOrDetached(query, database, table_uuid); } return res; } BlockIO InterpreterDropQuery::executeToDatabaseImpl(const ASTDropQuery & query, DatabasePtr & database, std::vector & uuids_to_wait) { const auto & database_name = query.database; auto ddl_guard = DatabaseCatalog::instance().getDDLGuard(database_name, ""); database = tryGetDatabase(database_name, query.if_exists); if (database) { if (query.kind == ASTDropQuery::Kind::Truncate) { throw Exception("Unable to truncate database", ErrorCodes::SYNTAX_ERROR); } else if (query.kind == ASTDropQuery::Kind::Detach || query.kind == ASTDropQuery::Kind::Drop) { bool drop = query.kind == ASTDropQuery::Kind::Drop; context.checkAccess(AccessType::DROP_DATABASE, database_name); if (query.kind == ASTDropQuery::Kind::Detach && query.permanently) throw Exception("DETACH PERMANENTLY is not implemented for databases", ErrorCodes::NOT_IMPLEMENTED); #if USE_MYSQL if (database->getEngineName() == "MaterializeMySQL") stopDatabaseSynchronization(database); #endif if (database->shouldBeEmptyOnDetach()) { /// DETACH or DROP all tables and dictionaries inside database. /// First we should DETACH or DROP dictionaries because StorageDictionary /// must be detached only by detaching corresponding dictionary. for (auto iterator = database->getDictionariesIterator(); iterator->isValid(); iterator->next()) { String current_dictionary = iterator->name(); executeToDictionary(database_name, current_dictionary, query.kind, false, false, false); } ASTDropQuery query_for_table; query_for_table.kind = query.kind; query_for_table.if_exists = true; query_for_table.database = database_name; query_for_table.no_delay = query.no_delay; for (auto iterator = database->getTablesIterator(context); iterator->isValid(); iterator->next()) { DatabasePtr db; UUID table_to_wait = UUIDHelpers::Nil; query_for_table.table = iterator->name(); executeToTableImpl(query_for_table, db, table_to_wait); uuids_to_wait.push_back(table_to_wait); } } /// Protects from concurrent CREATE TABLE queries auto db_guard = DatabaseCatalog::instance().getExclusiveDDLGuardForDatabase(database_name); if (!drop) database->assertCanBeDetached(true); /// DETACH or DROP database itself DatabaseCatalog::instance().detachDatabase(database_name, drop, database->shouldBeEmptyOnDetach()); } } return {}; } AccessRightsElements InterpreterDropQuery::getRequiredAccessForDDLOnCluster() const { AccessRightsElements required_access; const auto & drop = query_ptr->as(); if (drop.table.empty()) { if (drop.kind == ASTDropQuery::Kind::Detach) required_access.emplace_back(AccessType::DROP_DATABASE, drop.database); else if (drop.kind == ASTDropQuery::Kind::Drop) required_access.emplace_back(AccessType::DROP_DATABASE, drop.database); } else if (drop.is_dictionary) { if (drop.kind == ASTDropQuery::Kind::Detach) required_access.emplace_back(AccessType::DROP_DICTIONARY, drop.database, drop.table); else if (drop.kind == ASTDropQuery::Kind::Drop) required_access.emplace_back(AccessType::DROP_DICTIONARY, drop.database, drop.table); } else if (!drop.temporary) { /// It can be view or table. if (drop.kind == ASTDropQuery::Kind::Drop) required_access.emplace_back(AccessType::DROP_TABLE | AccessType::DROP_VIEW, drop.database, drop.table); else if (drop.kind == ASTDropQuery::Kind::Truncate) required_access.emplace_back(AccessType::TRUNCATE, drop.database, drop.table); else if (drop.kind == ASTDropQuery::Kind::Detach) required_access.emplace_back(AccessType::DROP_TABLE | AccessType::DROP_VIEW, drop.database, drop.table); } return required_access; } void InterpreterDropQuery::extendQueryLogElemImpl(QueryLogElement & elem, const ASTPtr &, const Context &) const { elem.query_kind = "Drop"; } }