UPDATE查询的WHERE子句中的SELECT查询

Question

可能重复:
Mysql错误1093 - 无法在FROM子句中指定更新目标表

将SELECT查询放在UPDATE查询的WHERE子句中时出错.

我的查询是这样的:

UPDATE `subschedulesseats` m
SET m.studentid='1'
WHERE m.`seatid`= (
    SELECT h.`seatid`
    FROM `subschedulesseats` h
    WHERE h.`sessiontime`='02:30~04:00'
    ORDER BY h.`seatid` ASC
    LIMIT 2,1
)

AND错误将显示如下:

"你不能在FROM子句中为更新指定目标表'm'"

我附上了错误显示的快照.

请有人帮我解决这个问题吗？

先感谢您

Answer 1

实际上你可以通过将它包装在子查询中来更新它(从而为结果创建临时表)

UPDATE `subschedulesseats` m
SET m.studentid='1'
WHERE m.`seatid`= 
(
    SELECT seatID
    FROM
    (
        SELECT h.`seatid`
        FROM `subschedulesseats` h
        WHERE h.`sessiontime`='02:30~04:00'
        ORDER BY h.`seatid` ASC
        LIMIT 2,1
    ) s
)

或者通过使用 JOIN

UPDATE  `subschedulesseats` m
        INNER JOIN
        (
            SELECT seatID
            FROM
            (
                SELECT h.`seatid`
                FROM `subschedulesseats` h
                WHERE h.`sessiontime`='02:30~04:00'
                ORDER BY h.`seatid` ASC
                LIMIT 2,1
            ) s
        ) t ON m.seatID = t.seatID
SET     m.studentid = '1'