Re: Re: Postgres slowdown on large table joins

* Dave Edmondson <david@jlc.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

>
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> David Edmondson <david@jlc.net>
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Larry Rosenman                     http://www.lerctr.org/~ler
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