题解 | #21年8月份练题总数#
21年8月份练题总数
http://www.nowcoder.com/practice/b8f30b239b454ed490367b53ea95607d
用户数 根据用户分组 题目总数,?未分组?
select count(did_cnt) , sum(question_cnt) from (select count(device_id) did_cnt,count(question_id) question_cnt from question_practice_detail t where t.date between str_to_date('2021-08-01','%Y-%m-%d') and str_to_date('2021-08-31','%Y-%m-%d') group by device_id) t