* Roland Bouman <[email protected]> [09/08/05 13:05]: > However, at some point I checked my assumptions with Konstantin > Osipov, and he told me that there is no guarantee the two tables are > updated atomically (at least not for MyISAM).
All tables used in a statement are locked at once, before execution. Then we update the first table, while accumulating PKs of the second table in a temporary table. Then we go over temporary table and update the rows in the second table, using the accumulated PKs. For MyISAM, this is as atomic as you get with LOCK TABLE t1 WRITE, t2 WRITE, and then running the two updates. -- _______________________________________________ Mailing list: https://launchpad.net/~drizzle-discuss Post to : [email protected] Unsubscribe : https://launchpad.net/~drizzle-discuss More help : https://help.launchpad.net/ListHelp
