题解 | #计算用户8月每天的练题数量#
计算用户8月每天的练题数量
http://www.nowcoder.com/practice/847373e2fe8d47b4a2c294bdb5bda8b6
select day(date) as day,count(question_id) as question_cnt
// day (date)意思是取这个这天的日子作为新表中day的字段取值
from question_practice_detail
where year(date)='2021' and month(date)='08'
//意思是取其中年份是2021，月份是08的
group by day
