groupBhv.delete(group, op -> {
            op.setRefreshPolicy(Constants.TRUE);
        });

        userBhv.selectCursor(cb -> cb.query().setGroups_Equal(group.getId()), entity -> {
            entity.setGroups(
                    stream(entity.getGroups()).get(stream -> stream.filter(s -> !s.equals(group.getId())).toArray(n -> new String[n])));
            userBhv.insertOrUpdate(entity);
        });

    }