问题描述

有关SQL的一个错误，来人帮忙看看吧

select ( sum( s.price * s.num ) + sum( o.freight ) ) as total
from pro_sold as s, pro_order as o,sys_merchant as m
where s.store_id=m.id=o.store_id
group by s.store_id

水平有限，实在没看出问题在哪里。
简单描述一下，查询出来的数字实在是超出我的心理极限呀。
太大了！
这是哪里出问题了？

解决方案

这没人帮你，sql语句本身语法没错，建议你检查你的数据是否正确，可以先不要求和，把符合条件的记录select处理，看看是不是这些数据

解决方案二：

select store_id,sum(total) as total
(select s.store_id, (s.price * s.num) as total
from pro_sold as s,sys_merchant as m
where s.store_id=m.id
group by s.store_id
union all
select o.store_id, o.freight as total
from pro_order as o,sys_merchant as m
where m.id=o.store_id
group by o.store_id
) a
group by store_id

解决方案三：

select ( sum( s.price * s.num ) + sum( o.freight ) ) as total
from pro_sold as s, pro_order as o,sys_merchant as m
where s.store_id=m.id And m.id=o.store_id=o.store_id
group by s.store_id

应该是少了一个And的问题。