How about to have relnamespace and relrole?

Hello,

Most of OID types has reg* OID types. Theses are very convenient
when looking into system catalog/views, but there aren't OID
types for userid and namespace id.

What do you think about having these new OID types? The
usefulness of regnamespace is doubtful but regrole should be
useful because the column like 'owner' appears many places.

For example this works as follows.

====
SELECT relnamespace::regnamespace, relname, relowner::regrole
FROM pg_class WHERE relnamespace = 'public'::regnamespace;

relnamespace | relname | relowner
--------------+---------+----------
public | t1 | horiguti
(1 row)

What do you think about this?

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center