Re: safe to overload objectSubId for a type?

Chapman Flack <chap@anastigmatix.net> writes:
> I don't mean "overload objectSubId" in any ObjectAddress that PG code
> would ever see. I am only thinking of a data structure of my own that
> is ObjectAddress-like and has all three components available all the
> time, and for an object that's a type, I would find it handy to stash
> a typmod there, and not have to carry those around separately.

If this is totally independent of ObjectAddress, why are you even
asking?  I assume that what you mean is you'd like these values to
bleed into ObjectAddresses or vice versa.

If we ever do make ObjectAddress.objectSubId mean something for types,
I'd expect --- based on the precedent of relation columns --- that it'd
specify a column number for a column of a composite type.  There are
fairly obvious use-cases for that, such as allowing a DROP of a column
type to not propagate to the whole composite type.  So I'd be pretty down
on allowing it to mean typmod instead.

            regards, tom lane