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题解 | #某乎问答高质量的回答中用户属于各级别的数量#

SELECT case when b.author_level in (1,2) then '1-2级' when b.author_level in (3,4) then '3-4级' when b.author_level in (5,6) then '5-6级'...

Mysql

2021-11-30

11 1799

题解 | #某乎问答11月份日人均回答量#

select answer_date, round(count(issue_id)/count(DISTINCT author_id),2) per_num from answer_tb where month(answer_date) = 11 group by answer_dat...

Mysql

2021-11-30

8 890

题解 | #各个视频的平均完播率#

SELECT a.video_id, round(sum(if((end_time-start_time-b.duration) >=0,1,0))/count(a.video_id),3) avg_comp_play_rate FROM tb_user_video_log a...

Mysql

2021-11-30

41 5745

题解 | #实习广场投递简历分析(三)#

select a.job, a.year_mon first_year_mon, a.k first_year_cnt, b.year_mon second_year_mon, b.k second_year_cnt from (select job, ...

Mysql

2021-11-29

0 293

题解 | #网易云音乐推荐(网易校招笔试真题)#

和大家分享一下我的解题思路，抛砖引玉首先三表连接 select a.user_id , a.follower_id , b.music_id , c.music_name from follow a left join music_likes b on a.follower_id = b.user...

Mysql

2021-11-29

1 443

题解 | #牛客每个人最近的登录日期(二)#

select u_n, c_n, date from ( select b.name u_n, c.name c_n, date, RANK() OVER (PARTITION BY b.name ORDER BY date DESC) AS...

Sqlite Mysql

2021-11-29

0 232

题解 | #浙大不同难度题目的正确率#

select difficult_level, sum(if(result='right',1,0))/count(*) correct_rate from question_practice_detail a left join question_detail b on a.ques...

Mysql

2021-11-22

1 296

题解 | #统计每种性别的人数#

select a.device_id, university, sum(case when month(date)='08' then 1 when month(date) is null then 0 end) ques...

Mysql

2021-11-22

1 310

题解 | #统计每种性别的人数#

使用 find_in_set() 函数也可，见貌似暂时没人用这个方法，分享给大家 SELECT case when FIND_IN_SET('male',profile) then 'male' when FIND_IN_SET('female',profile) the...

Mysql

2021-11-22

13 417