From: Jaime Casanova <systemguards@gmail.com>
To: Marc G. Fournier <scrappy@postgresql.org>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-sql@postgresql.org
Subject: Re: Putting an INDEX on a boolean field?
Date: Fri, 17 Jun 2005 00:42:22 -0500
Message-ID: <c2d9e70e0506162242557a7e65@mail.gmail.com> (raw)
In-Reply-To: <20050617020039.P90456@ganymede.hub.org>
References: <20050617011336.Q90456@ganymede.hub.org>
<15887.1118983309@sss.pgh.pa.us>
<20050617020039.P90456@ganymede.hub.org>
On 6/17/05, Marc G. Fournier <scrappy@postgresql.org> wrote:
> On Fri, 17 Jun 2005, Tom Lane wrote:
>
> > "Marc G. Fournier" <scrappy@postgresql.org> writes:
> >> Does that make sense? Would it ever get used?
> >
> > It could get used if one of the two values is far less frequent than the
> > other. Personally I'd think about a partial index instead ...
>
> Hrmmmm, hadn't thought of that ... wouldn't you have to build two indexes
> (one for true, one for false) for this to be completely effective? unless
> you know all your queries are going to search for one, but not the other?
>
I guess it will be effective only if you know wich value will be less
frequent... on the other value a sequential scan will be a win, isn't
it?
--
regards,
Jaime Casanova
(DBA: DataBase Aniquilator ;)
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To: pgsql-sql@postgresql.org
Cc: systemguards@gmail.com, scrappy@postgresql.org, tgl@sss.pgh.pa.us
Subject: Re: Putting an INDEX on a boolean field?
In-Reply-To: <c2d9e70e0506162242557a7e65@mail.gmail.com>
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