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题解 | #连续两次作答试卷的最大时间窗#

select uid ,days_window ,round(ct/all_day*days_window,2) avg_exam_cnt from( select uid ,max(ifnull(days_window,0))+1 ...

2023-04-16

0 190

题解 | #第二快/慢用时之差大于试卷时长一半的试卷#

with temp as( select t1.exam_id ,duration ,release_time ,timestampdiff(minute,start_time,submit_time) diff ,row_number() over(par...

2023-04-10

0 218

题解 | #每个6/7级用户活跃情况#

with temp as ( select a.uid, exam_id, start_time, submit_time, score ...

2023-03-22

0 215

题解 | #满足条件的用户的试卷完成数和题目练习数#

注意把NULL值转换成0 with temp as ( select t1.uid from exam_record t1 left join examination_info t2 ...

2023-03-21

0 208

题解 | #分别满足两个活动的人#

select distinct uid, "activity1" as activity from exam_record t1 left join examination_info t2 on t1.exam_id = t2.exam_id where ye...

2023-03-21

0 285

题解 | #每个题目和每份试卷被作答的人数和次数#

select * from( ( select exam_id as tid, count(distinct uid) uv, count(start_time) pv from exam_record grou...

2023-03-21

0 212

题解 | #作答试卷得分大于过80的人的用户等级分布#

select level, count(distinct t1.uid) as level_cnt from exam_record t1 left join examination_info t2 on t1.exam_id = t2.exam_id lef...

2023-03-21

0 173

题解 | #试卷发布当天作答人数和平均分#

select t1.exam_id, count(distinct t1.uid) as uv, round(avg(ifnull(score,0)),1) as avg_score from exam_record t1 left join examinat...

2023-03-21

0 245

题解 | #月均完成试卷数不小于3的用户爱作答的类别#

select tag,count(start_time) as tag_cnt from exam_record t1 left join examination_info t2 on t1.exam_id = t2.exam_id where uid in ( select uid ...

2023-03-20

1 197

题解 | #月均完成试卷数不小于3的用户爱作答的类别#

select tag,count(start_time) as tag_cnt from exam_record t1 left join examination_info t2 on t1.exam_id = t2.exam_id where uid in ( select uid fr...

2023-03-20

1 221