关于#sql#的问题，请各位专家解答！

Question

根据学生运动的数据，sql统计上个月每天参与运动的人有多少。

Answer 1

    SELECT
    sum( count )
    FROM
    (
    SELECT
    count( DISTINCT studentId ) AS count,
    date_format( from_unixtime( createDate / 1000 ), '%Y-%m-%d' ) AS date
    FROM
    sp_student sss
    where 
     sss.createDate >= #{startTime}
      and sss.createDate <= #{endTime}
    GROUP BY
    date ) t