SELECT Activity, arat.Amount "Total Amount 2008", abull.Amount AS "Total Amount 2009"
FROM
Activities a
LEFT OUTER JOIN
(
SELECT ActivityId, SUM(Amount) AS Amount
FROM Incomes ibull
GROUP BY
ibull.ActivityId
) abull
ON abull.ActivityId = a.ActivityID
LEFT OUTER JOIN
(
SELECT ActivityId, SUM(Amount) AS Amount
FROM Incomes2008 irat
GROUP BY
irat.ActivityId
) arat
ON arat.ActivityId = a.ActivityID
WHERE a.UnitName = ?
ORDER BY Activity
Я ввел определение типа, которое, на мой взгляд, несколько прояснило его:
class A
{
typedef void (*FPTR)(int a, char c);
static FPTR cb;
};
A::FPTR A::cb = NULL;