一、Update
二、多表关联更新
1)例一
update payee_account a,machine b set a.ACCOUNT_ALIAS=b.MACHINE_NAME
where b.line_account = a.login_no;
2)列二
update xcs_user_credit_score a1 inner join xcs_user_credit_score a2 on a1.uid=a2.uid
set a1.user_currday_score=a1.user_currday_increment_score+a2.user_currday_score
where a1.pt_day='2017-09-20' and a2.pt_day='2017-09-19';