Re: Why does a simple query not use an obvious index? - Mailing list pgsql-performance

From Scott Marlowe
Subject Re: Why does a simple query not use an obvious index?
Date
Msg-id 1093815855.5493.33.camel@localhost.localdomain
Whole thread Raw
In response to Re: Why does a simple query not use an obvious index?  ("Scott Marlowe" <smarlowe@qwest.net>)
List pgsql-performance
On Sun, 2004-08-29 at 15:38, Scott Marlowe wrote:
> On Sun, 2004-08-29 at 15:12, Greg Stark wrote:
> > "Scott Marlowe" <smarlowe@qwest.net> writes:
> >
> > > Also, count(*) is likely to always generate a seq scan due to the way
> > > aggregates are implemented currently in pgsql.  you might want to try:
> >
> > Huh? I'm curious to know what you're talking about here.
>
> This has been discussed ad infinitum on the lists in the past.  And
> explained by better minds than mine, but I'll give it a go.
>
> PostgreSQL has a "generic" aggregate method.  Imagine instead doing a
> select count(id1+id2-id3) from table where ...

that should be avg(id1+id2-id3)... doh


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