Message-ID: <5123518F.30206@basenlily.me>
Date: Tue, 19 Feb 2013 21:18:55 +1100
From: Bastiaan Olij <bastiaan@basenlily.me>
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To: pgsql-performance@postgresql.org
Subject: Re: Speed of exist
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Hi Pavel,

That is what I've done in this particular case but there are parts where
I use exist checks in this way that are very cumbersome to write out
like that so I'm hoping there is a way to make the optimizer work with
existence checks in this way.

Cheers,

Bastiaan Olij

On 19/02/13 6:39 PM, Pavel Stehule wrote:
> 2013/2/19 Bastiaan Olij <bastiaan@basenlily.me>:
>> Hi Andy,
>>
>> I've tried that with the same result. One subquery works beautifully,
>> two subqueries with an OR and it starts to do a sequential scan...
> try to rewrite OR to two SELECTs joined by UNION ALL
>
> Pavel
>


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