Citat:
SELECT p.ProductID, p.name, ki.UserID, SUM(IF(ki.kolicina IS NULL,0,ki.kolicina)) AS kolicina
FROM proizvodi AS p
LEFT JOIN kupci_interakcije AS ki ON p.ProductID = ki.PorductID
GROUP BY p.ProductID
Ovako?
"Common sense is not so common." - Voltaire