Re: PL/pgSQL return value in after triggers

2012/1/2 Peter Eisentraut <peter_e(at)gmx(dot)net>:
> On mån, 2011-02-28 at 19:07 +0200, Peter Eisentraut wrote:
>> PL/pgSQL trigger functions currently require a value to be returned,
>> even though that value is not used for anything in case of a trigger
>> fired AFTER.  I was wondering if we could relax that.  It would make
>> things a bit more robust and produce clearer PL/pgSQL code.  The
>> specific case I'm concerned about is that a trigger function could
>> accidentally be run in a BEFORE trigger even though it was not meant for
>> that.  It is common practice that trigger functions for AFTER triggers
>> return NULL, which would have unpleasant effects if used in a BEFORE
>> trigger.
>>
>> I think it is very uncommon to have the same function usable for BEFORE
>> and AFTER triggers, so it would be valuable to have coding support
>> specifically for AFTER triggers.  We could just allow RETURN without
>> argument, or perhaps no RETURN at all.
>
> Here is a patch for that.
>

+1

> One thing that I'm concerned about with this is that it treats a plain
> RETURN in a BEFORE trigger as RETURN NULL, whereas arguably it should be
> an error.  I haven't found a good way to handle that yet, but I'll keep
> looking.

-1

the change of behave is significant in this case and is better require
some specific symbol. RETURN NULL is good for me.

Regards

Pavel

>
>
>
> --
> Sent via pgsql-hackers mailing list (pgsql-hackers(at)postgresql(dot)org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-hackers
>