Обсуждение: Is there a reason why no table OID in pg_tables

I was just trying to compare constraints in two versions of a database and the 
obvious (to me) join from pg_constraint to pg_tables wasn't possible.

Not a real problem, I just used pg_class, but is the lack of oid in pg_tables 
a design decision and if so why?

--  Richard Huxton Archonet Ltd

Richard Huxton <dev@archonet.com> writes:
> Not a real problem, I just used pg_class, but is the lack of oid in pg_tables
> a design decision and if so why?

Views don't have OIDs (or any other system columns).  We could export
pg_class.oid as an ordinary column in pg_tables, but then it would be
in your face whether you wanted it or not.
        regards, tom lane

On Saturday 18 October 2003 16:32, Tom Lane wrote:
> Richard Huxton <dev@archonet.com> writes:
> > Not a real problem, I just used pg_class, but is the lack of oid in
> > pg_tables a design decision and if so why?
>
> Views don't have OIDs (or any other system columns).

And if they did, it wouldn't be what we wanted anyway.

>  We could export
> pg_class.oid as an ordinary column in pg_tables, but then it would be
> in your face whether you wanted it or not.

Fair enough - it just seemed odd that a FK in pg_constraint would refer to an 
oid that wasn't available "at the same level of abstraction" if you see what 
I mean.

--  Richard Huxton Archonet Ltd