根据 MySQL 文档，要进行交叉表更新，您不能使用连接(就像在其他数据库中一样)，而是使用 where 子句:

According to MySQL documentation, to do a cross table update, you can't use a join (like in other databases), but instead use a where clause:

http://dev.mysql.com/doc/refman/5.0/en/update.html

我认为这样的事情应该可行:

I think something like this should work:

UPDATE User_Settings, Contacts
    SET User_Settings.Contact_ID = Contacts.ID
    WHERE User_Settings.Account_ID = Contacts.Account_ID