题解 | 21年8月份练题总数
21年8月份练题总数
https://www.nowcoder.com/practice/b8f30b239b454ed490367b53ea95607d
select
COUNT(distinct device_id) as did_cnt,
COUNT(question_id) as question_cnt
from question_practice_detail
where date like '2021-08%%'
别忘了加distinct
