From: Zoltan Boszormenyi <zboszor@dunaweb.hu>
To: Jim C. Nasby <jnasby@pervasive.com>
Cc: Volkan YAZICI <yazicivo@ttnet.net.tr>
Cc: pgsql-performance@postgresql.org
Subject: Re: Precomputed constants?
Date: Thu, 15 Jun 2006 06:31:02 +0200
Message-ID: <4490E286.90004@dunaweb.hu> (raw)
In-Reply-To: <20060614151804.GB34196@pervasive.com>
References: <3167.213.163.11.81.1150282434.squirrel@www.dunaweb.hu>
<20060614110713.GA2277@alamut.tdm.local>
<3861.213.163.11.81.1150284610.squirrel@www.dunaweb.hu>
<20060614151804.GB34196@pervasive.com>
Jim C. Nasby írta:
> On Wed, Jun 14, 2006 at 01:30:10PM +0200, B?sz?rm?nyi Zolt?n wrote:
>
>> Replacing random() with a true constant gives me index scan
>> even if it's hidden inside other function calls. E.g.:
>>
>
> The database has no choice but to compute random() for every row; it's
> marked VOLATILE.
>
I see now, docs about CREATE FUNCTION mentions random(),
currval() and timeofday() as examples for VOLATILE.
But where in the documentation can I find this info about all
built-in functions? Thanks.
Best regards,
Zoltán Böszörményi
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To: pgsql-performance@postgresql.org
Cc: zboszor@dunaweb.hu, jnasby@pervasive.com, yazicivo@ttnet.net.tr
Subject: Re: Precomputed constants?
In-Reply-To: <4490E286.90004@dunaweb.hu>
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