From: PFC <lists@boutiquenumerique.com>
To: K C Lau <KCLau@attglobal.net>
To: pgsql-performance@postgresql.org
Subject: Re: SELECT DISTINCT Performance Issue
Date: Mon, 06 Jun 2005 13:45:39 +0200
Message-ID: <op.srx5mdsmth1vuj@localhost> (raw)
In-Reply-To: <6.2.1.2.0.20050602190756.05ab2c70@localhost>
References: <6.2.1.2.0.20050602190756.05ab2c70@localhost>
> Previously, we have also tried to use LIMIT 1 instead of DISTINCT, but
> the performance was no better:
> select PlayerID,AtDate from Player where PlayerID='22220' order by
> PlayerID desc, AtDate desc LIMIT 1
The DISTINCT query will pull out all the rows and keep only one, so the
one with LIMIT should be faster. Can you post explain analyze of the LIMIT
query ?
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: lists@boutiquenumerique.com, KCLau@attglobal.net
Subject: Re: SELECT DISTINCT Performance Issue
In-Reply-To: <op.srx5mdsmth1vuj@localhost>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox