题解 | #今天的刷题量(一)#
今天的刷题量(一)
https://www.nowcoder.com/practice/e18f56796ae94c3d885e61c8d57a950e
select t2.name,count(subject_id) as cnt from submission as t1 left join subject as t2 on t1.subject_id=t2.id where t1.create_time= current_date group by subject_id,t2.name order by cnt desc,subject_id asc
1.返回当前日期 current_date 或curdate(）
2.分组的时候注意 group by t1.name,t2.subject_id（名字和题单id相同分到一组），不能仅仅subject_id分组
