On Wed, 20 Apr 2005, Christopher Kings-Lynne wrote:
> Hi,
>
> Can you put a foreign key constraint on an array column that says that
> each element of the array must match a primary key?
Not currently, because foreign keys are between directly comparable
things.
> If not, is this a TODO perhaps?
Maybe. It's been discussed before IIRC. Doing the referential actions
might get tricky, and you'd often want to index so that finding the
individual array elements isn't expensive.