题解 | 国庆期间近7日日均取消订单量
国庆期间近7日日均取消订单量
https://www.nowcoder.com/practice/2b330aa6cc994ec2a988704a078a0703
select
dt,
round(count(start_time) / 7, 2) as finish_num_7d,
round(sum(cancel_number) / 7, 2) as cancel_num_7d
from
(select distinct date(order_time) as dt
from tb_get_car_order
where
date(order_time) between '2021-10-01' and '2021-10-03'
) as target_time
left join (select
date(order_time) as random_date,
date(start_time) as start_time,
if(start_time is null, 1, 0) as cancel_number
from tb_get_car_order
) as random_time on datediff(dt, random_date) between 0 and 6
group by dt
order by dt;
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