Re: Crash Recovery

Noah Silverman <noah(at)allresearch(dot)com> writes:
> I'm curious about where I can find documentation about crash recovery in
> postgres. In mysql, there is a nice table recovery utility (myisamchk).
> is there something similar in postgres?

There are no automated recovery tools for Postgres, because there are
no known failure modes that are systematic enough to allow automatic
recovery. We prefer to fix such bugs rather than patch around them.

There are some last-ditch tools for reconstructing indexes (REINDEX)
and for throwing away the WAL log (pg_resetxlog) but I have not seen
any recent cases where I would have felt that blind invocation of either
would be a good move.

> What do we do if a table or
> database becomes corrupted? (I'm aware of backup techniques, but it isn't
> feasible for some of our larger tables.

Reconsider that. If your data center burns down tonight, what is your
fallback? Ultimately, you *must* have a backup copy, or you're just not
taking the possibility of failure seriously.

regards, tom lane