Re: CREATE AGGREGATE disallows STYPE = internal

"Robert Haas" <robertmhaas@gmail.com> writes:
> On Fri, Nov 14, 2008 at 10:12 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> "Robert Haas" <robertmhaas@gmail.com> writes:
>>> I would feel a lot better about it if we could invent some way of
>>> distinguishing between different types of "internal", based on what is
>>> actually being pointed to.
>> 
>> Yeah, we discussed that awhile ago, but nothing's been done about it.
>> At this point I doubt it will happen for 8.4.

> That's a shame.  Do you happen to have a pointer to the relevant
> discussions in the archives?

http://archives.postgresql.org/pgsql-hackers/2008-08/msg00644.php

> Without that, it seems that the change you're proposing is totally
> unsafe.  It's not just a question of malicious activity: a clueless
> admin (a category we've all been in from time to time...) could
> relatively easily create a configuration that crashes the backend.

It's no more dangerous than allowing the admin to create functions
taking or returning internal to begin with.  Basically, if you are
superuser, there are no training wheels.
        regards, tom lane