Finding users to shred

Hi Folks,
Does anyone have a query or a script that can find users
in the database who aren’t referenced by any tickets?
I’d like to find users who were created by spam who
are now candidates for shredding.
Regards,
-Chuck Boeheim

There is an example for this in rt-wiki.:
rt-shredder --plugin "Users=no_tickets,1;status,any;replace_relations,Nobody;limit,5" --sqldump /{somepath}/shredder-restore-users.sql --force

Petr