题解 | #有取消订单记录的司机平均评分#

1.筛选出有过退单记录的司机

select driver_id
from tb_get_car_order
where 
start_time is null

2.统计分数平均，保留一位小数

round(avg(grade),1)

3.汇总列

ifnull(driver_id,'总体')
with rollup

最终的sql

select ifnull(driver_id,'总体'), round(avg(grade),1)
from tb_get_car_order
where driver_id in
(select driver_id
from tb_get_car_order
where 
start_time is null)
group by driver_id
with rollup