> I think you're pretty well screwed as far as getting it *all* back goes,
> but you could use pg_resetxlog to back up the NextXID counter enough to
> make your tables and databases reappear (and thereby lose the effects of
> however many recent transactions you back up over).
>
> Once you've found a NextXID setting you like, I'd suggest an immediate
> pg_dumpall/initdb/reload to make sure you have a consistent set of data.
> Don't VACUUM, or indeed modify the DB at all, until you have gotten a
> satisfactory dump.
>
> Then put in a cron job to do periodic vacuuming ;-)
This might seem like a stupid question, but since this is a massive data
loss potential in PostgreSQL, what's so hard about having the
checkpointer or something check the transaction counter when it runs and either issue a db-wide vacuum if it's about
towrap, or simply
disallow any new transactions?
I think people'd rather their db just stopped accepting new transactions
rather than just losing data...
Chris