题解 | #商品交易(网易校招笔试真题)#

#不管是内连接还是左右连接，只要存在重复值，一定是重复连接后返回到新表，也就是说左1，右2，肯定就是1X2

select
distinct goods.id
,goods.name
,goods.weight
,a1.t1 as total
from
goods left join
(
select
*
,sum(count)over(partition by goods_id) as t1
from trans
) as a1
on 
goods.id = a1.goods_id
where a1.t1>=20 and weight<50
order by goods.id