Re: vacuum analyze slows sql query

From: Gaetano Mendola <mendola(at)bigfoot(dot)com>
To: patrick ~ <sidsrr(at)yahoo(dot)com>
Subject: Re: vacuum analyze slows sql query
Date: 2004-11-11 08:03:24
Message-ID: 41931CCC.6070803@bigfoot.com
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patrick ~ wrote:
> --- John Meinel <john(at)johnmeinel(dot)com> wrote:
>
>
>>If you are trying to establish existence, we also had a whole thread on
>>this. Basically what we found was that adding an ORDER BY clause, helped
>>tremendously in getting the planner to switch to an Index scan. You
>>might try something like:
>>
>>SELECT column FROM mytable WHERE column='myval' ORDER BY column LIMIT 1;
>>
>>There seems to be a big difference between the above statement and:
>>
>>SELECT column FROM mytable WHERE column='myval' LIMIT 1;
>
>
>
> The ORDER BY "trick" worked beautifully! I just hope it'll
> continue to work consistently in production code.

For sure it will not break the goal: "check the existence".

Regards
Gaetano Mendola

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