Question

我的MySQL下面给出了错误。

UPDATE P SET P.author_name = A.name 
FROM POSTS AS P INNER JOIN AUTHORS AS A
ON P.author_id = A.id;

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 
'FROM POSTS AS P INNER JOIN AUTHORS AS A
ON P.author_id = A.id' at line 2

但是，选择正常。

select P.id, a.name
FROM POSTS AS P INNER JOIN AUTHORS AS A
ON P.author_id = A.id;

我无法弄清楚我做错了什么，有什么帮助？

Answer 1

UPDATE POSTS 
INNER JOIN AUTHORS ON POSTS.author_id = AUTHORS.id;
SET POSTS.author_name = AUTHORS.name

Answer 2

对于MySql，您需要首先对JOIN进行编码，然后再对SET语句进行编码：

UPDATE POSTS INNER JOIN AUTHORS ON POSTS.author_id = AUTHOR.id
SET POSTS.author_name = AUTHOR.name

选择MySQL更新错误

2 个答案: