note 76504 deleted from function.mysql-insert-id by cmb

Note Submitter: guelphdad at yahoo dot com ---- and the primary reason to use neither of those last two solutions is both could result in race conditions when there is more than a single user with access to the database. when you use MAX or ORDER BY DESC LIMIT 1 you will retrieve the maximum value from the table, at that moment. That doesn't mean another user doesn't do an insertion in the primary and secondary table BEFORE you do your insertion in the secondary table. You have thus inserted a row with a correct id into the second table. Always use last_insert_id()