Re: Proposed feature: Selective Foreign Keys

Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
>>> Well I guess we could say something like:
>>>
>>> FOREIGN KEY (a-col) WHERE (a-condition) REFERENCES b(b-col) WHERE
>>> (b-condition)
>>>
>>> But it's somewhat ugly.

> OK, those make sense. I wonder whether this should be done via a USING
> clause on the constraint that pointed to the partial unique index. Or
> would that be too obscure?

I like what you have above. Yeah, it requires the more verbose syntax
for declaring a foreign key, but this feature is not going to be so
heavily used that anyone will be in danger of worsening their carpal
tunnel syndrome.

regards, tom lane