Re: Consistent pg_dump's

Alfred Perlstein <bright@wintelcom.net>

From: Alfred Perlstein <bright@wintelcom.net>
To: Doug McNaught <doug@wireboard.com>
Cc: pgsql-general@postgresql.org
Date: 2001-03-29T23:49:21Z
Lists: pgsql-general
* Doug McNaught <doug@wireboard.com> [010329 15:22] wrote:
> Alexey Rodriguez Yakushev <alexey@serinbol.com> writes:
> 
> > Let me rephrase the question, i have a web-based application which uses 
> > postgres as its backend. It must be operating 24 hours 7 days. If i want to 
> > make a backup of the database using pg_dump, wouldn't it be possible that a 
> > transaction occurs in the middle of the backup, leaving the backup 
> > inconsistent?
> 
> I am pretty sure that pg_dump produces a consistent snapshot, using
> the same transaction isolation mechanism (MVCC) as the database
> itself.  If one of the gurus posts and says otherwise, believe him,
> not me.  ;)

My impression from reading the source was that it was consitant per-table
but not per-database.  Meaning you'd get a consistant snapshot of a table,
but not of the entire system.

I could be wrong though.

-- 
-Alfred Perlstein - [bright@wintelcom.net|alfred@freebsd.org]
Represent yourself, show up at BABUG http://www.babug.org/