select b.ID, b.Datum, b.Kod, sum(b.suma)
from pracovnici b
where b.Kod = (select max(a.kod) from pracovnici a where a.ID=b.ID and a.Datum=b.Datum)
group by b.ID, b.Datum, b.Kod;
select b.ID, b.Datum, b.Kod, sum(b.suma)
from pracovnici b
where b.Kod = (select max(a.kod) from pracovnici a where a.ID=b.ID and a.Datum=b.Datum)
group by b.ID, b.Datum, b.Kod;