Re: Re: Postgres slowdown on large table joins

On Mon, Feb 19, 2001 at 08:34:47PM -0600, Larry Rosenman wrote:
> * Dave Edmondson <david(at)jlc(dot)net> [010219 14:40]:
> > > > yes. I ran VACUUM ANALYZE after creating the indicies. (Actually, I VACUUM
> > > > the database twice a day.) The data table literally has 145972 rows, and
> > > > 145971 will match conf_id 4...
> > >
> > > Hm. In that case the seqscan on data looks pretty reasonable ... not
> > > sure if you can improve on this much, except by restructuring the tables.
> > > How many rows does the query actually produce, anyway? It might be that
> > > most of the time is going into sorting and delivering the result rows.
> >
> > All I'm really trying to get is the latest row with a conf_id of 4... I'm
> > not sure if there's an easier way to do this, but it seems a bit ridiculous
> > to read in almost 146000 rows to return 1. :(
>
> is there a timestamp or date/time tuple in the row? If so, index
> THAT.
>
> LER

actually, just did that yesterday... now that I finally understand incides.
Thanks anyway.

--
David Edmondson <david(at)jlc(dot)net>
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