My code is ok, but if have values from 0 to 999 it's ok. Example two values 500.00 and 80.00 result is 580.00 that is ok. Example if have two values 1,000.00 and 100.00 sum result is 100.00
select kupac as 'Kupac',
SUM(TRY_CONVERT(Decimal(10, 2), ISNULL(NULLIF(iznos_sa_pdv, ''), '0'))) AS 'UKUPNO'
from(select kupac, iznos_sa_pdv from mp_faktura_lista union all select kupac, iznos_sa_pdv from mp_racun_lista) as alltables
group by kupac
Some help?