Re: check_foreign_key

On Wed, 30 Apr 2003, [iso-8859-1] Erik Ronstrm wrote:

> The help document for CREATE TRIGGER shows an example of "simulating" a
> foreign key by creating a trigger with a call to check_foreign_key (I
> guess it has exactly the same result as using FOREIGN KEY?).

AFAIK that's a reference to the spi contrib item refint, not the foreign
key code itself (whose trigger names are more like "RI_FKey_check_ins")

> But what does the first argument to check_foreign_key really mean? And
> to take the question further: are the internal functions/procedurs
> documented somewhere? I've not been able to find any documentation of

Often they aren't.

> check_foreign_key (for example), and it doesn't even show up when
> typing \df at the psql prompt.

Yeah, it won't show up unless you install it. Seems like it might not be
such a good example if it doesn't mention that.