educoder第3关：任务3：CTGU实验3_4-查询12
use library;######### Begin #########
## -- 12、在USER表中添加一个金额字段amount，类型decimal。并对每个用户的交费总额进行修改alter table Users add amount decimal;
update Users,(select sum(amount) as amount,loanNo from Money group by loanNo ) as t
set Users.amount=t.amount
where Users.loanNo=t.loanNo;######### End ##########select loanNo,lname,amount from Users where amount is not NULL order by loanNo;本文来自互联网用户投稿，文章观点仅代表作者本人，不代表本站立场，不承担相关法律责任。如若转载，请注明出处。 如若内容造成侵权/违法违规/事实不符，请点击【内容举报】进行投诉反馈！