immutable function calling stable function
am 21.07.2004 16:04:37 von twanger
Hi,
shouldn't it be illegal for an immutable function to call a stable one?
--
Markus Bertheau
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Re: immutable function calling stable function
am 21.07.2004 16:45:34 von tgl
Markus Bertheau 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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Re: immutable function calling stable function
am 21.07.2004 16:51:20 von sszabo
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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