题解 | #有取消订单记录的司机平均评分#

我的笨办法：用union all 实现

select driver_id,round(avg(grade),1)as avg_grade

from tb_get_car_order

where driver_id in

(select driver_id

from tb_get_car_order

where month (order_time)=10

and start_time is null)

and grade is not null

group by 1

union all

select "总体" as driver_id,round(avg(grade),1)as avg_grade

from tb_get_car_order

where driver_id in

(select driver_id

from tb_get_car_order

where month (order_time)=10

and start_time is null)

and grade is not null;