mysql - 我的 MySQL 语句有什么问题？

Question

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

#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'a where a.username=table1.announcer)' at line 1

Answer 1

尝试:

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