MySQL错误：您无法在FROM子句中为更新指定目标表'users_words'

Question

请查看我的MySQL条款。

UPDATE `users_words` SET `priority` = (SELECT MAX(`priority`)+1 FROM `users_words`) where `userid` = 89 AND `wordid`="agree"

在这里，我将通过在现有的最大priority字段值中加1来更新priority字段。但我收到错误You can't specify target table 'users_words' for update in FROM clause。

如何解决此问题？

Answer 1

将子查询包装在另一个SELECT：

中

UPDATE `users_words` 
SET `priority` = (SELECT x.* FROM (SELECT MAX(`priority`)+1 FROM `users_words`) x) 
WHERE `userid` = 89 AND `wordid`="agree"