会计中的余额求解SQL

SELECT *, 
(SELECT SUM(AD_in-AD_out) FROM account_Detail AS AD2 WHERE ((AD2.ADate = AD.ADate AND AD2.idno <= AD.idno) or (AD2.Adate < Ad.ADate)) ) as TotalCount
FROM account_Detail AS AD WHERE Year(ADate) = 2004 AND Month(ADate) = 7 
ORDER BY AD.ADate,AD.idno