mgr inż. Jacek Bzdak <jbzdak@gmail.com> writes:
> Maybe just fix pg_stat_activity so it uses LEFT JOIN, to cover such case. I
> guess it shouldnt break any code?
Meh ... that would result in the usename column being possibly NULL,
which I bet applications aren't expecting either. I'm not necessarily
against this, but I'm not sure it'll make things much better.
Anybody else have an opinion?
(Of course, the real fix would be to prevent dropping user IDs that
correspond to any live session, but that's not terribly easy either,
especially if you think about transient settings such as SET ROLE.
Overall I'm not convinced this is a case worth spending a lot of
effort on.)
regards, tom lane