Re: Use of systable_beginscan_ordered in event trigger patch

On Wed, Dec 12, 2012 at 3:51 PM, Dimitri Fontaine
<dimitri(at)2ndquadrant(dot)fr> wrote:
> Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:
>>> Maybe we could just append to it how to remove such an event trigger,
>>> which is easy to do because you can't target an event trigger related
>>> command with event triggers, so the following is not disabled:
>>> DROP EVENT TRIGGER abort_ddl;
>>
>> Oh really? The explanation of the example certainly doesn't say that.
>
> I remember than in my proposals somewhere we had support for a very
> limited form of command triggers for any command in the system. Of
> course as that included transaction control commands we made that
> better. I'm quite tired so maybe my memory is playing tricks to me, but
> I kind of remember that we also had quite a discussion about just that
> example and its phrasing in the docs and did came out with something
> satisfactory.
>
> Robert, does that ring a bell to you? I'm going to crawl the archives
> tomorrow if not…

Yeah, I'm pretty sure you can't set event triggers of any kind on
event triggers. You proposed to allow some stuff that would affect
"every command", but I yelled and screamed about that until we got rid
of it, 'cuz it just seemed way too dangerous.

--
Robert Haas
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