Re: Conflicting constraint being merged

Amit Langote <Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp> writes:
> Currently, if child table has a non-inherited constraint and a constraint
> with the same name is added to the parent, it will fail with an error as
> illustrated below:
> ...
> If we had allowed it to be merged, any children of child itself won't
> inherit that constraint (because on child it's marked NO INHERIT), which
> would not be good.

Right. Merging must happen only for inheritable constraints.

> However, it is still possible for a child to override/hide the parent's
> constraint as follows:

Hmm, I thought I'd checked for this when I was fooling with constraint
merging a few days ago. I must have checked one of the other cases and
missed this path. Thanks for catching it!

regards, tom lane