Hi,

shouldn't it be illegal for an immutable function to call a stable one?

--
Markus Bertheau <twanger [at] bluetwanger.de>


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Markus Bertheau <twanger [at] bluetwanger.de> writes:
> shouldn't it be illegal for an immutable function to call a stable one?

No, because that's the standard hack for getting around it when you wish
to call a stable function in what you know to be a "safe" way. If you
look in the archives you'll find cases where creating an immutable
wrapper function was the recommended solution to performance problems.

regards, tom lane

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On Wed, 21 Jul 2004, Markus Bertheau wrote:

> shouldn't it be illegal for an immutable function to call a stable one?

It's expected that the function's creator is responsible for properly
marking its stability. This allows some flexibility when you know more
than the system does (for example, a stable function that isn't immutable
because of its use of a GUC variable being called from a function that
sets said variable).

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