From: Lew <noone@lewscanon.com>
To: pgsql-sql@postgresql.org
Subject: Re: Question regarding indices
Date: Sat, 11 Sep 2010 11:08:00 -0400
Message-ID: <i6g60e$345$1@news.albasani.net> (raw)
In-Reply-To: <20100911122923.75010@gmx.net>
References: <20100911122923.75010@gmx.net>
On 09/11/2010 08:29 AM, Steve wrote:
> I have a small question about the order of values in a query.
> Assume I have a table with the following fields:
> uid INT,
> data BIGINT,
> hits INT
> And an unique index on (uid, data). I use libpq C API to query
> data from the table. The query is something like this:
> SELECT uid,data,hits FROM mytable WHERE uid=2
> AND data IN (2033,2499,590,19,201,659)
>
> Would the speed of the query be influenced if I would sort the data?
What do you mean by "sort the data"? Which data?
> I can imagine that just querying a bunch of bigint would not make a
> big difference but what about several thousand of values? Would sorting
> them and sending the SQL query with ordered data influence the speed of the query?
Send the query from where to where?
Are you referring to a sort of the items in the IN subselect? My guess is
that sorting that won't matter but it's only a WAG.
--
Lew
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To: pgsql-sql@postgresql.org
Cc: noone@lewscanon.com
Subject: Re: Question regarding indices
In-Reply-To: <i6g60e$345$1@news.albasani.net>
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