Sql Server 与 MySql 在使用 update inner join 时的区别

Sql Server

update tb_User
set pass = ‘‘-- 此处pass前不要加 tb_User 别名usr
from tb_User usr
inner join tb_Address addr on usr.nAddressFK = addr.nAddressID
where usr.id=123  

MySql

UPDATE mem_world AS mw1 INNER JOIN mem_world AS mw2
ON mw1.parentid = mw2.wid
SET mw1.level = mw2.level
WHERE mw2.baseid = 107
AND mw2.parentid = 0
AND mw2.size > 1; 

一个是先set再关联，另外一个是先关联再set。