题解 | 统计各岗位员工平均工作时长
统计各岗位员工平均工作时长
https://www.nowcoder.com/practice/b7220791a95a4cd092801069aefa1cae
#算出一天工作多少小时，要过滤掉为空的时间，再求平均值 select post, sum(round(hour(timediff(last_clockin,first_clockin)) + minute(timediff(last_clockin,first_clockin))/60 +second(timediff(last_clockin,first_clockin))/3600,3))/count(1) work_hours from attendent_tb a left join staff_tb s on a.staff_id = s.staff_id where first_clockin is not null and last_clockin is not null group by post order by work_hours desc