Re: Two questions about "pg_constraint"

Bryn Llewellyn <bryn@yugabyte.com> writes:
> My other question was about the "connamespace" column. It seemed to me,
> both at first and still now, that this is a clear instance of a
> transitive dependency.

I think a more productive way to think about it is that it's
denormalization for efficiency; specifically to let constraints
be looked up by name+namespace without having to get other
catalogs involved.  (SET CONSTRAINTS is one thing that requires
that, and I think there are others.)

            regards, tom lane