j a wrote:
> From my reading, I can use PITR recovery to restore my database to its
> state just prior to a recent change (not even an hour ago). The
> erroneous change resulted from an UPDATE with no WHERE on a small
> table (<700 rows); I mention this only in case there is a simpler
> recovery technique I can use for such a small subset of the entire
> database.
You can do this if you have a PITR backup. That is , you made a PITR
backup some time ago and wish to use all of the WAL files since then and
the time that you want to recover to to restore. You cannot simply "go
backwards" from the current database state, regardless of the WAL files
you have at your disposal.
>
> The docs state that restore_command is required in recovery.conf, and
> that the server will check pg_xlog/ for any requested files not found
> in the specified archive location.
>
> Can I use a command that points to an empty directory as the archive
> location to force checks to pg_xlog? Or is there some 'cleaner' way?
If you made a PITR backup at some point in the past you would have at
least a couple of files in your WAL archive directory..
>
> Also, I read in another post (about v8.1) that the WAL records are
> written in 16MB segments. If the WAL containing my recovery target
> hasn't been written yet, how can I determine when it has and is
> available to me?
>
> I'm running 8.2 on CentsOS 5, if it matters any.
--
Chander Ganesan
Open Technology Group, Inc.
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919-463-0999/866-229-3386
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