Re: Trigger question

In article <24300.1074614549@sss.pgh.pa.us>,
Tom Lane <tgl@sss.pgh.pa.us> writes:

> Richard Huxton <dev@archonet.com> writes:
>> On Tuesday 20 January 2004 00:01, Neil Conway wrote:
>>> Yeah, I didn't get around to implementing that. If anyone wants this
>>> feature, I'd encourage them to step up to the plate -- I'm not sure
>>> when I'll get the opportunity/motivation to implement this myself.

>> I didn't think they'd be meaningful for a statement-level trigger. Surely
>> OLD/NEW are by definition row-level details.

> According to the complainants, OLD/NEW are commonly available as
> recordsets (tables) inside a statement trigger.

Yes.

> I'm not very clear on
> how that works myself --- in particular, one would think it important to
> be able to work with corresponding pairs of OLD and NEW rows, which
> would be painful with a table-like abstraction.

Why?  If the underlying table has a primary key, finding corresponding
pairs is trivial; if there isn't, it's impossible.