1、明确3张表的含义：
①tb_order_overall：用户订单信息表 as t1
②tb_order_detail：用户订单中商品及其售价表 as t2（t1.order_id = t2.order_id）
③tb_product_info：用户订单中商品及其进价表 as t3（t2.product_id = t3.product_id）

2、明确需求：
①店铺汇总的毛利率【店铺总毛利率 = (1-总进价成本/总销售收入)*100% = (1-sum(t3.in_price*t2.cnt)/sum(t2.price*t2.cnt))】
②毛利率大于24.9%的product_id及其毛利率【各个商品的毛利率 = (1-进价/平均单件售价)*100% = (1-sum(t3.in_price*t2.cnt)/sum(t2.price*t2.cnt))】

3、具体操作
step1：分别按照需求，创建两张表
Ⅰ、
select '店铺汇总' as product_id,【由于第1个字段并未进行分组，因此后续的聚合函数就是对全部店铺商品进行的汇总计算】
concat(round((1-sum(t3.in_price*t2.cnt)/sum(t2.price*t2.cnt))*100,1),'%') as profit_rate

from tb_order_overall as t1
left join tb_order_detail as t2
on t1.order_id = t2.order_id
left join tb_product_info as t3
on t2.product_id = t3.product_id

where date_format(event_time,'%Y%m') >= '202110'【event_time VS release_time：客户下单时间√ 商品上架时间×】
and status = 1【用户在付款后并无其它操作】
and t1.shop_id = 901【店铺901】


Ⅱ、
select t2.product_id as product_id,
concat(round((1-sum(t1.in_price * t2.cnt)/sum(t2.price * t2.cnt))*100,1),'%') as profit_rate

from tb_order_overall as t1
left join tb_order_detail as t2
on t1.order_id = t2.order_id
left join tb_product_info as t3
on t2.product_id = t3.product_id

where date_format(event_time,'%Y%m') >= '202110'【event_time VS release_time：客户下单时间√ 商品上架时间×】
and status = 1【用户在付款后并无其它操作】
and t1.shop_id = 901【店铺901】

group by 1
having replace(profit_rate,'%','') > 24.9【商品毛利率大于24.9%的商品信息】

step2：将两张表按照需求关联起来
xxx  union all  xxxx