Question

UPDATE table1 SET announcer = ( SELECT memberid
FROM ( table1
JOIN users ON table2.username = table1.announcer
) AS a
WHERE a.username = table1.announcer )

＃1064 - 您的SQL语法出错;检查手册对应于您的MySQL服务器用于正确语法的版本靠近'一个地方 a.username = table1.announcer）” 在第1行

Answer 1

尝试：

UPDATE announcements a
SET announcer =
(SELECT memberid
FROM users u
WHERE u.username = a.announcer)

Answer 2

您也可以在UPDATE中进行JOIN

UPDATE announcements JOIN users
SET announcements.announcer=users.memberid
WHERE announcements.username=users.username;

注意：出于安全原因（直到你确定的播音员被复制过来）我会创建一个新专栏，比如播音员新的

UPDATE announcements JOIN users
SET announcements.announcerNew=users.memberid
WHERE announcements.username=users.username;

我的MySQL声明出了什么问题？

2 个答案: