"Jonah H. Harris" <jonah.harris@gmail.com> writes:
> I've run into a couple cases now where it would be helpful to easily
> assign an already-existing unique index as a primary key.
You need to present a more convincing use-case than this unsupported
assertion. There's hardly any effective difference between a unique
index + NOT NULL constraints and a declared primary key ... so what
did you really need it for?
> 1. Verify that the index named is a unique index
... and not partial, and not on expressions, and not invalid, and not
using non-default opclasses (which might have a surprising definition of
"equal"), and not already owned by a constraint ... not to mention that
it'd better be an index on the named table, which among other things
removes the need for a schema specification on the index name.
regards, tom lane