"Tony Webb" <amw(at)sanger(dot)ac(dot)uk> writes:
> I can grant table privileges to the USER and RO but how do I stop these
> two users from creating new tables etc?
Revoke CREATE privilege on the public schema from PUBLIC (and then grant
it back to OWNER and whoever else you want to have it).
If you don't want them creating temp tables either, similarly revoke
the database-level TEMP privilege.
regards, tom lane