I have a list of contracts like this query:
select
r.vnum, r.BEITRAGSGR
from
ufrisk r
inner join
ufvert v on r.vnum = v.vnum
inner join
allgvert a on a.vnum = r.vnum
where
a.version = r.version
How can I search for all contracts that have more than one (different) value in the column r.BEITRAGSGR?
