Fabien COELHO <coelho(at)cri(dot)ensmp(dot)fr> writes:
> I notice that some tables in pg_catalog have oids, and some do not have
> them (e.g. pg_attribute, pg_group, pg_shadow...).
That's not a bug, it's a feature. We don't use up OIDs on tables that
don't need them.
regards, tom lane