| From: | "David G(dot) Johnston" <david(dot)g(dot)johnston(at)gmail(dot)com> |
|---|---|
| To: | Joel Mukuthu <jom(at)upright(dot)co> |
| Cc: | pgsql-bugs(at)lists(dot)postgresql(dot)org |
| Subject: | Re: Unexpected behaviour of a RAISE statement in an IMMUTABLE function |
| Date: | 2022-11-23 16:14:48 |
| Message-ID: | CAKFQuwY=t2HXng-0pAZtxk89zpTGAF-i_QVB-naazhFUmRVt3A@mail.gmail.com |
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| Lists: | pgsql-bugs |
On Wed, Nov 23, 2022 at 9:01 AM Joel Mukuthu <jom(at)upright(dot)co> wrote:
>
> Given the following two functions, where the only difference between them
> is that one is VOLATILE while the other is IMMUTABLE:
>
>
That is a huge difference
> Is this behaviour expected?
>
>
Yes.
RAISE is a side-effect inducing statement, which disqualifies the function
from being IMMUTABLE.
The immutable marker gives the system permission to execute the function,
given constant arguments, once to find out what the value of that function
is during the execution of the query and make decisions based upon that
result.
David J.
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| Next Message | Tom Lane | 2022-11-23 16:20:26 | Re: Unexpected behaviour of a RAISE statement in an IMMUTABLE function |
| Previous Message | PG Bug reporting form | 2022-11-23 14:46:47 | BUG #17693: Slow performance: Much slower queries on pg_stat_all_tables since 13.4 |