Maybe I've misread, but can't you force a session that has a sessID/timestamp that pushes that ID to the client, then upon submission, it is caught upon POST? That way, if they refresh, you can put a unique ID in the session to do what you want of it. If I'm understanding you correctly (and I may not be), you could keep the info in the session for the db id, and eliminate it as necessary as the session refreshes/times-out.

Or use a proper Revision Control System to fix all of your problems.

-stevieb