问下这个SQL的写法
本帖最后由 u011669689 于 2013-09-25 18:25:00 编辑 基础条件：
user表 userid ,username
user_money 表 u_id,user_money
user_money_exchange 表：money ,username,ordertag =1或2
现在想执行：
update user_money set user_money = (user_money_exchange 当ordertag =1的 sum(money) + 当ordertag =2的 sum(money)） where user_money.u_id = user.userid
update user_money
set user_money.money =
(select sum(ume.money) as m , u.userid from user_money_exchange ume left join user u on ume.username = u.username where ume.ordertag = 1 group by ume.username
+
select sum(ume.money) as m , u.userid from user_money_exchange ume left join user u on ume.username = u.username where ume.ordertag = 2 group by ume.username)
where user_money.u_id = u.userid
update user_money um left join user u on um.u_id=u.userid
left join
(select username,sum(money) as moneys from user_money_exchange group by username) ume
on ume.username=u.username
set um.money = ume.moneys
