[ Samo polako @ 23.10.2005. 21:34 ] @
Imam tri tabele tabela:sf ------- s ------- 1 2 3 4 ------- tabela:n1 ---------- sifra...a ---------- 1.......10 2.......11 3.......13 4.......14 ---------- tabela:n2 ---------- sifra...a ---------- 1.......1 2.......3 4.......6 ---------- upit: select s, (select sum (a) from n1 where sifra=sf.s) as A, (select sum (a) from n2 where sifra=sf.s) as B, (select sum (a) from n1 where sifra=sf.s) - (select sum (a) from n2 where sifra=sf.s) as AMB from sf rezultat: ----------------------------- s.......A.......B.......AMB ----------------------------- 1.......10......1.......9 2.......11......3.......8 3.......13......NULL..NULL 4.......14......6.......8 ----------------------------- što je i logično jer u tabeli n2 ne postoje podaci sa sifrom 3 ono sto zelim je da umjeso NULL u slucaju sifre 3 dobijem nulu (0) i da samim tim rezultat u koloni AMB bude 13-0=13 Jeli moguće to uraditi onako kako sam zamislio? Hvala unapred! |