题解 | #今天的刷题量(一)#

# 用curdate()来返回今天的日期
select name, cnt
from (
    select subject_id, count(*) cnt
    from submission
    where create_time = curdate()
    group by subject_id
) t1
join subject s
on t1.subject_id = s.id
order by cnt desc, subject_id;