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Date: Tue, 11 Nov 2025 13:43:53 +0100
From: hubert depesz lubaczewski <depesz@depesz.com>
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To: Heikki Linnakangas <hlinnaka@iki.fi>
Cc: PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Subject: Re: Functions used by index don't need to be immutable?
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On Tue, Nov 11, 2025 at 02:43:18PM +0200, Heikki Linnakangas wrote:
> In case of SQL functions, the immutability check can inline or "see through"
> the definition and determine that the expression used in the function
> doesn't contain any immutable expressions. If you modify get_tsvector,
> adding a random() to it for example, then you will get the error.

Ah, makes sense. Thanks a lot.

Best regards,

depesz