SQL更新其连接值的SUM

Question

我正在尝试将数据库中的字段更新为其连接值的总和:

UPDATE P
SET extrasPrice = SUM(E.price)
FROM dbo.BookingPitchExtras AS E
INNER JOIN dbo.BookingPitches AS P ON E.pitchID = P.ID
    AND P.bookingID = 1
WHERE E.[required] = 1

当我运行这个时,我收到以下错误:

"An aggregate may not appear in the set list of an UPDATE statement."

有任何想法吗？

Answer 1

这个怎么样:

UPDATE p
SET p.extrasPrice = t.sumPrice
FROM BookingPitches AS p
INNER JOIN
    (
        SELECT PitchID, SUM(Price) sumPrice
        FROM BookingPitchExtras
        WHERE [required] = 1
        GROUP BY PitchID 
    ) t
    ON t.PitchID = p.ID
WHERE p.bookingID = 1

Answer 2

上述解决方案的替代方法是使用表的别名:

UPDATE T1 SET T1.extrasPrice = (SELECT SUM(T2.Price) FROM BookingPitchExtras T2 WHERE T2.pitchID = T1.ID)
FROM BookingPitches T1;