mysql无法使用select和subselect指定目标表并选择

Question

我有这个问题：

UPDATE answers AS aa SET aa.question_id=(SELECT q.id FROM question AS q WHERE q.question LIKE (SELECT a.question_prev FROM answers AS a))

错误：

  

mysql无法指定目标表

无法弄清楚如何编辑它才能正常工作

Answer 1

试试这个，

UPDATE  answers a
        INNER JOIN question b
            ON b.question = a.question_prev
SET     a.question_id = b.id

请在执行语句前先备份。