Helper\Db::getMysql()->prepare('UPDATE `tbl` SET `active` = false WHERE `user` = 1');
Helper\Db::getMysql()->prepare('UPDATE `tbl` SET `active` = true WHERE `user` = 1 AND `id = 1`');
стало
Helper\Db::getMysql()->prepare('UPDATE `tbl` SET `active` = false WHERE `user` = 1'
UNION
UPDATE `tbl` SET `active` = true WHERE `user` = 1 AND `id = 1`');