Re: IMMUTABLE function's flag do not work: 7.3.4, plpgsql - Mailing list pgsql-performance

From Andriy Tkachuk
Subject Re: IMMUTABLE function's flag do not work: 7.3.4, plpgsql
Date
Msg-id 20031010101408.G35607-100000@pool.imt.com.ua
Whole thread Raw
In response to Re: IMMUTABLE function's flag do not work: 7.3.4, plpgsql  (Gaetano Mendola <mendola@bigfoot.com>)
Responses Re: IMMUTABLE function's flag do not work: 7.3.4, plpgsql
List pgsql-performance
On Thu, 9 Oct 2003, Gaetano Mendola wrote:

> Andriy Tkachuk wrote:
> > On Wed, 8 Oct 2003, Tom Lane wrote:
> >
> >
> >>Andriy Tkachuk <ant@imt.com.ua> writes:
> >>
> >>>At second. calc_total() is immutable function:
> >>>but it seems that it's not cached in one session:
> >>
> >>It's not supposed to be.
> >
> >
> > but it's written id doc:
> >
> >               IMMUTABLE indicates that the function always  returns  the  same
> >               result when given the same argument values; that is, it does not
> >               do database lookups or otherwise use  information  not  directly
> >               present in its parameter list. If this option is given, any call
> >               of the function with all-constant arguments can  be  immediately
> >               replaced with the function value.
>
> The doc say "can be" not must and will be.

ok, but on what it depends on?

thanks,
 andriy

http://www.imt.com.ua


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