Re: TB-sized databases

On Tue, 2007-11-27 at 18:06 -0500, Pablo Alcaraz wrote:
> Simon Riggs wrote:
> > All of those responses have cooked up quite a few topics into one. Large
> > databases might mean text warehouses, XML message stores, relational
> > archives and fact-based business data warehouses.
> >
> > The main thing is that TB-sized databases are performance critical. So
> > it all depends upon your workload really as to how well PostgreSQL, or
> > another other RDBMS vendor can handle them.
> >
> >
> > Anyway, my reason for replying to this thread is that I'm planning
> > changes for PostgreSQL 8.4+ that will make allow us to get bigger and
> > faster databases. If anybody has specific concerns then I'd like to hear
> > them so I can consider those things in the planning stages
> it would be nice to do something with selects so we can recover a rowset
> on huge tables using a criteria with indexes without fall running a full
> scan.
>
> In my opinion, by definition, a huge database sooner or later will have
> tables far bigger than RAM available (same for their indexes). I think
> the queries need to be solved using indexes enough smart to be fast on disk.

OK, I agree with this one.

I'd thought that index-only plans were only for OLTP, but now I see they
can also make a big difference with DW queries. So I'm very interested
in this area now.

--
  Simon Riggs
  2ndQuadrant  http://www.2ndQuadrant.com