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
https://www.nowcoder.com/practice/847373e2fe8d47b4a2c294bdb5bda8b6
select
day(date) as day,
count(question_id) as question_cnt
from question_practice_detail
where month(date)=8 and year(date)=2021
group by date
- 限定条件：2021年8月，写法有很多种，比如用year/month函数的
year(date)=2021 and month(date)=8，比如用date_format函数的date_format(date, "%Y-%m")="202108" - 每天：按天分组
group by date - 题目数量：count(question_id)
