Re: Big 7.1 open items

"Philip J. Warner" <pjw@rhyme.com.au> writes:
>> ... the thing that bothered me was this.  Suppose you are trying to
>> recover a corrupted database manually, and the only information you have
>> about which table is which is a somewhat out-of-date listing of OIDs
>> versus table names.

> This worries me a little; in the Dec/RDB world it is a very long time since
> database backups were done by copying the files. There is a database
> backup/restore utility which runs while the database is on-line and makes
> sure a valid snapshot is taken. Backing up storage areas (table spapces)
> can be done separately by the same utility, and again, it records enough
> information to ensure integrity. Maybe the thing to do is write a pg_backup
> utility, which in a first pass could, presumably, be synonymous with pg_dump?

pg_dump already does the consistent-snapshot trick (it just has to run
inside a single transaction).

> Am I missing something here? Is there a problem with backing up using
> 'pg_dump | gzip'?

None, as long as your ambition extends no further than restoring your
data to where it was at your last pg_dump.  I was thinking about the
all-too-common-in-the-real-world scenario where you're hoping to recover
some data more recent than your last backup from the fractured shards
of your database...
        regards, tom lane