At 11:06 PM 11/30/00 -0800, Vadim Mikheev wrote:
>> As for replaying logs against a restored snapshot dump... AIUI, a
>> dump records tuples by OID, but the WAL refers to TIDs. Therefore,
>> the WAL won't work as a re-do log to recover your transactions
>> because the TIDs of the restored tables are all different.
>
>True for current way of backing up - ie saving data in "external"
>(sql) format. But there is another way - saving data files in their
>natural (binary) format. WAL records may be applyed to
>such dump, right?
Right. That's what's missing in PG 7.1, the existence of tools to
make such backups.
Probably the best answer to the "what does WAL get us, if it doesn't
get us full recoverability" questions is to simply say "it's a prerequisite
to getting full recoverability, PG 7.1 sets the foundation and later
work will get us there".
- Don Baccus, Portland OR <dhogaza@pacifier.com> Nature photos, on-line guides, Pacific Northwest Rare Bird Alert
Serviceand other goodies at http://donb.photo.net.