Tom Lane wrote:
> Stephan Szabo <sszabo@megazone.bigpanda.com> writes:
> > On Mon, 22 Sep 2003, Jean-Christian Imbeault wrote:
> >> Is it right for postgres to accept a foreign key constraint when the
> >> type of the field is not the same as that of the foreign key?
>
> > IIRC in SQL92 it's said that they need to be the same type, but in SQL99
> > it says that the two types must be comparable. We basically implement the
> > latter, basically using the existance of a usable equality operator as the
> > determination of comparable.
>
> Note however that performance may be poor with a cross-type foreign key
> reference, if the planner is unable to figure out how to use an index
> for the check queries.
Didn't we agree to throw a NOTICE in cases of a mismatch? (I think
Peter agreed to a NOTICE but not a WARNING) Is that completed?
--
Bruce Momjian | http://candle.pha.pa.us
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