题解 | 三表连接
三表连接
https://www.nowcoder.com/practice/c86c980ce4544959b4691448c937620e
with t as (select 订单号,商品号,支付金额,包裹号,总运费,商品类型 from 订单表 join 运费表 using(订单号,商品号) join 品类表 using(商品号)) select 商品类型,sum(支付金额) as 支付金额, sum(总运费) as 总运费, sum(总运费)/sum(支付金额) as 运费占比 from t group by 商品类型
