Re: [HACKERS] GSoC 2017: Foreign Key Arrays

On Wed, Jul 19, 2017 at 11:08 PM, Alvaro Herrera <alvherre@2ndquadrant.com> wrote:

I'm not entirely sure what's the best way to deal with the polymorphic
problem, but on the other hand as Robert says downthread maybe we
shouldn't be solving it at this stage anyway.  So let's step back a bit,
get a patch that works for the case where the types match on both sides
of the FK, then we review that patch; if all is well, we can discuss the
other problem as a stretch goal.

+1

Regular FK functionality have type restrictions based on btree opfamilies and implicit casts.  Array FK should not necessary have the same type restrictions.  Also, we don't necessary need to make those restrictions as soft as possible during this GSoC project.