"Donald Fraser" <postgres@kiwi-fraser.net> writes:
> 1) Was there a good reason for dropping this feature?
Users/groups are identified by OIDs now, not by sysids.
The original motivation for allowing manual assignment of userids was to
allow recovery if a user was dropped while still owning objects --- you
could recreate the user with the same sysid and then the objects' owner
fields would match up. 8.1 now does reference counting and prevents you
from dropping users who still own anything, so AFAICS that use-case is
gone. Do you have another one?
regards, tom lane