Re: Re: Postgres slowdown on large table joins

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От Dave Edmondson
Тема Re: Re: Postgres slowdown on large table joins
Дата
Msg-id 20010219152451.A61259@verdi.jlc.net
обсуждение исходный текст
Ответ на Postgres slowdown on large table joins  (Dave Edmondson <david@jlc.net>)
Ответы Re: Re: Postgres slowdown on large table joins  (Larry Rosenman <ler@lerctr.org>)
Список pgsql-general
> > 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. :(

--
David Edmondson <david@jlc.net>
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