题解 | 统计加班员工占比

select
    department,
    concat (round(sum(判断) / count(*) * 100, 1), '%') ratio
from
    (
        select
            department,
            timestampdiff (minute, first_clockin, last_clockin) 分钟数,
            if (
                timestampdiff (minute, first_clockin, last_clockin) > 570,
                1,
                0
            ) 判断
        from
            test.staff_tb st
            join test.attendent_tb att on st.staff_id = att.staff_id
    ) a
group by
    department
order by
    ratio desc