Re: Control File

On Thu, Apr 13, 2006 at 04:39:59AM -0400, Bruce Momjian wrote:
> Tom Lane wrote:
> > Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > > Bruno Almeida do Lago wrote:
> > >> After that night, I started to ask myself if PostgreSQL should not have a
> > >> control file to check if expected datafiles are where they should be and
> > >> JUST warn about missing ones?
> >
> > > I don't think this happens frequently enough to add code for it.
> >
> > I think we saw it happen once to Joe Conway's DB. But I see no
> > particular reason why Postgres needs a feature for this --- you can
> > stick a test into your database start script if you need it.
>
> Right, that is the only other time I remember it.

The difference now is that we have tablespaces, which makes this
scenario more likely. Previously I suspect common practice was to either
leave everything in $PGDATA, or at most to move pg_xlog somewhere else
and symlink it in, and I'm guessing that the databse will complain
loudly if it can't find pg_xlog. So I suspect this will become far more
common. As for adding checks to startup scripts, that's a PITA because
those scripts will have no idea of where tablespaces might be defined,
so you'd have to hard-code that info in.
--
Jim C. Nasby, Sr. Engineering Consultant jnasby(at)pervasive(dot)com
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461