"Shridhar Daithankar" <shridhar_daithankar@persistent.co.in> writes:
> I would say keep range of user specified ids and automatically generated ids
> exclusive to each other.
No, that won't do. The principal reason why we keep the explicit SYSID
option around at all is so that a DBA can deliberately recreate a user
with the same SYSID he had before, in case the user is dropped by
mistake leaving objects or permissions behind. So we can't just forbid
conflicts completely.
regards, tom lane