老北京2018

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题解 | #近三个月未完成试卷数为0的用户完成情况#

写点不一样的解法 uid, exam_complete_cnt from ( select r.uid, sum(submit_time is not null) exam_complete_cnt from exam_record r where (uid, date_fo...

Mysql

2021-11-25

0 294

题解 | #连续两次作答试卷的最大时间窗#

select a.uid, days_window, round(b.`avg` * a.days_window, 2)avg_exam_cnt from ( select uid, max(days_window)days_window from ( select u...

Mysql

2021-11-24

0 295

题解 | #获得积分最多的人(二)#

select g.user_id, u.name, g.grade_num from ( select user_id, sum(grade_num) grade_num from `grade_info` group by user_id)g left join `use...

Mysql

2021-10-15

0 309

题解 | #商品交易(网易校招笔试真题)#

select g.id,g.name,g.weight,t.total from goods g left join (select goods_id,sum(count) total from trans group by goods_id) t on g.id = t.goods_id wh...

Mysql

2021-10-15

0 225

题解 | #浙大不同难度题目的正确率#

select d.difficult_level,sum(if(pd.`result`='right',1,0))/count(1) correct_rate from (select device_id from user_profile where university = '浙江大学') u ...

Mysql

2021-10-11

0 221