def _set_session_sql_mode(dbapi_con, connection_rec, connection_proxy, sql_mode=None): """Set the sql_mode session variable. MySQL supports several server modes. The default is None, but sessions may choose to enable server modes like TRADITIONAL, ANSI, several STRICT_* modes and others. Note: passing in '' (empty string) for sql_mode clears the SQL mode for the session, overriding a potentially set server default. Passing in None (the default) makes this a no-op, meaning if a server-side SQL mode is set, it still applies. """ cursor = dbapi_con.cursor() if sql_mode is not None: cursor.execute("SET SESSION sql_mode = %s", [sql_mode]) # Check against the real effective SQL mode. Even when unset by # our own config, the server may still be operating in a specific # SQL mode as set by the server configuration cursor.execute("SHOW VARIABLES LIKE 'sql_mode'") row = cursor.fetchone() if row is None: LOG.warning(_LW('Unable to detect effective SQL mode')) return realmode = row[1] LOG.info(_LI('MySQL server mode set to %s') % realmode) # 'TRADITIONAL' mode enables several other modes, so # we need a substring match here if not ('TRADITIONAL' in realmode.upper() or 'STRICT_ALL_TABLES' in realmode.upper()): LOG.warning(_LW("MySQL SQL mode is '%s', " "consider enabling TRADITIONAL or STRICT_ALL_TABLES") % realmode)
def drop_old_duplicate_entries_from_table(migrate_engine, table_name, use_soft_delete, *uc_column_names): """Drop all old rows having the same values for columns in uc_columns. This method drop (or mark ad `deleted` if use_soft_delete is True) old duplicate rows form table with name `table_name`. :param migrate_engine: Sqlalchemy engine :param table_name: Table with duplicates :param use_soft_delete: If True - values will be marked as `deleted`, if False - values will be removed from table :param uc_column_names: Unique constraint columns """ meta = MetaData() meta.bind = migrate_engine table = Table(table_name, meta, autoload=True) columns_for_group_by = [table.c[name] for name in uc_column_names] columns_for_select = [func.max(table.c.id)] columns_for_select.extend(columns_for_group_by) duplicated_rows_select = select(columns_for_select, group_by=columns_for_group_by, having=func.count(table.c.id) > 1) for row in migrate_engine.execute(duplicated_rows_select): # NOTE(boris-42): Do not remove row that has the biggest ID. delete_condition = table.c.id != row[0] is_none = None # workaround for pyflakes delete_condition &= table.c.deleted_at == is_none for name in uc_column_names: delete_condition &= table.c[name] == row[name] rows_to_delete_select = select([table.c.id]).where(delete_condition) for row in migrate_engine.execute(rows_to_delete_select).fetchall(): LOG.info(_LI("Deleting duplicated row with id: %(id)s from table: " "%(table)s") % dict(id=row[0], table=table_name)) if use_soft_delete: delete_statement = table.update().\ where(delete_condition).\ values({ 'deleted': literal_column('id'), 'updated_at': literal_column('updated_at'), 'deleted_at': timeutils.utcnow() }) else: delete_statement = table.delete().where(delete_condition) migrate_engine.execute(delete_statement)
def _set_session_sql_mode(dbapi_con, connection_rec, connection_proxy, sql_mode=None): """Set the sql_mode session variable. MySQL supports several server modes. The default is None, but sessions may choose to enable server modes like TRADITIONAL, ANSI, several STRICT_* modes and others. Note: passing in '' (empty string) for sql_mode clears the SQL mode for the session, overriding a potentially set server default. Passing in None (the default) makes this a no-op, meaning if a server-side SQL mode is set, it still applies. """ cursor = dbapi_con.cursor() if sql_mode is not None: cursor.execute("SET SESSION sql_mode = %s", [sql_mode]) # Check against the real effective SQL mode. Even when unset by # our own config, the server may still be operating in a specific # SQL mode as set by the server configuration cursor.execute("SHOW VARIABLES LIKE 'sql_mode'") row = cursor.fetchone() if row is None: LOG.warning(_LW('Unable to detect effective SQL mode')) return realmode = row[1] LOG.info(_LI('MySQL server mode set to %s') % realmode) # 'TRADITIONAL' mode enables several other modes, so # we need a substring match here if not ('TRADITIONAL' in realmode.upper() or 'STRICT_ALL_TABLES' in realmode.upper()): LOG.warning( _LW("MySQL SQL mode is '%s', " "consider enabling TRADITIONAL or STRICT_ALL_TABLES") % realmode)