题解 | #月总刷题数和日均刷题数#
月总刷题数和日均刷题数
http://www.nowcoder.com/practice/f6b4770f453d4163acc419e3d19e6746
select date_format(submit_time,'%Y%m') submit_month
,count(id) month_q_cnt
,round(count(id)/avg(day(last_day(submit_time))),3) avg_day_q_cnt
from practice_record
where score is not null
and year(submit_time) = '2021'
group by date_format(submit_time,'%Y%m')
union all
select '2021汇总' submit_month,count(id) month_q_cnt
,round(count(id)/31,3) avg_day_q_cnt
from practice_record
where score is not null
and year(submit_time) = '2021'
order by submit_month;
