From: Evgeny Gridasov <eugene@i-free.ru>
To: Dan Harris <fbsd@drivefaster.net>
Cc: pgsql-performance@postgresql.org
Subject: Re: Help optimizing a slow index scan
Date: Fri, 17 Mar 2006 22:32:53 +0300
Message-ID: <20060317223253.38c0e6b9.eugene@i-free.ru> (raw)
In-Reply-To: <441ADB88.9010701@drivefaster.net>
References: <4419DB50.10404@drivefaster.net>
<4419DC1C.9070806@drivefaster.net>
<684362e10603161915x431c6b08t@mail.gmail.com>
<441AD702.9020508@drivefaster.net>
<441ADB88.9010701@drivefaster.net>
Try contrib/btree_gist.
I've tried that one, but for my case it didn't help much.
The performance was almost equal or even slower than built-in btree.
On Fri, 17 Mar 2006 08:53:44 -0700
Dan Harris <fbsd@drivefaster.net> wrote:
> Dan Harris wrote:
> > Markus Bertheau wrote:
> >> Have you tried using a GIST index on lat & long? These things are
> >> meant for two-dimensional data, whereas btree doesn't handle
> >> two-dimensional data that well. How many rows satisfy either of the
> >> long / lat condition?
> >>
> >>
> >>>
> > According to the analyze, less than 500 rows matched. I'll look into
> > GIST indexes, thanks for the feedback.
> >
> > -Dan
> >
> > ---------------------------(end of broadcast)---------------------------
> > TIP 2: Don't 'kill -9' the postmaster
>
> When I try to create a GIST index, I get the following error:
>
> create index eventgeo_lat_idx on eventgeo using GIST (lat);
>
> ERROR: data type double precision has no default operator class for
> access method "gist"
> HINT: You must specify an operator class for the index or define a
> default operator class for the data type.
>
> I'm not sure what a "default operator class" is, exactly..
>
> -Dan
>
> ---------------------------(end of broadcast)---------------------------
> TIP 5: don't forget to increase your free space map settings
>
--
Evgeny Gridasov
Software Engineer
I-Free, Russia
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To: pgsql-performance@postgresql.org
Cc: eugene@i-free.ru, fbsd@drivefaster.net
Subject: Re: Help optimizing a slow index scan
In-Reply-To: <20060317223253.38c0e6b9.eugene@i-free.ru>
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