Re: Precomputed constants?

From: Zoltan Boszormenyi <zboszor(at)dunaweb(dot)hu>
To: "Jim C(dot) Nasby" <jnasby(at)pervasive(dot)com>
Cc: Volkan YAZICI <yazicivo(at)ttnet(dot)net(dot)tr>, pgsql-performance(at)postgresql(dot)org
Subject: Re: Precomputed constants?
Date: 2006-06-15 04:31:02
Message-ID: 4490E286.90004@dunaweb.hu
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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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