Function BrojRac(Prefix As String)
Dim db As Database
Dim SQL As String
Dim rs As Recordset
Dim i As Integer

Set db = CurrentDb

SQL = "SELECT Max(Left([OrderID],1)) FROM tblProdaja WHERE Mid(OrderID,3,4)= '" & Prefix & "'"

Set rs = db.OpenRecordset(SQL)

If Format$(rs.Fields(0)) <> "" Then
i = Val(rs.Fields(0))
End If
i = i + 1
BrojRac = i & "/" & Prefix & "/1"

rs.Close
Set db = Nothing
End Function