【牛客】SQL134 满足条件的用户的试卷完成数和题目练习数

描述

现有用户信息表user_info（uid用户ID，nick_name昵称, achievement成就值, level等级, job职业方向, register_time注册时间）：

id	uid	nick_name	achievement	level	job	register_time
1	1001	牛客1号	3100	7	算法	2020-01-01 10:00:00
2	1002	牛客2号	2300	7	算法	2020-01-01 10:00:00
3	1003	牛客3号	2500	7	算法	2020-01-01 10:00:00
4	1004	牛客4号	1200	5	算法	2020-01-01 10:00:00
5	1005	牛客5号	1600	6	C++	2020-01-01 10:00:00
6	1006	牛客6号	2000	6	C++	2020-01-01 10:00:00

试卷信息表examination_info（exam_id试卷ID, tag试卷类别, difficulty试卷难度, duration考试时长, release_time发布时间）：

id	exam_id	tag	difficulty	duration	release_time
1	9001	SQL	hard	60	2021-09-01 06:00:00
2	9002	C++	hard	60	2021-09-01 06:00:00
3	9003	算法	medium	80	2021-09-01 10:00:00

试卷作答记录表exam_record（uid用户ID, exam_id试卷ID, start_time开始作答时间, submit_time交卷时间, score得分）：

id	uid	exam_id	start_time	submit_time	score
1	1001	9001	2021-09-01 09:01:01	2021-09-01 09:31:00	81
2	1002	9002	2021-09-01 12:01:01	2021-09-01 12:31:01	81
3	1003	9001	2021-09-01 19:01:01	2021-09-01 19:40:01	86
4	1003	9002	2021-09-01 12:01:01	2021-09-01 12:31:51	89
5	1004	9001	2021-09-01 19:01:01	2021-09-01 19:30:01	85
6	1005	9002	2021-09-01 12:01:01	2021-09-01 12:31:02	85
7	1006	9003	2021-09-07 10:01:01	2021-09-07 10:21:01	84
8	1006	9001	2021-09-07 10:01:01	2021-09-07 10:21:01	80

题目练习记录表practice_record（uid用户ID, question_id题目ID, submit_time提交时间, score得分）：

id	uid	question_id	submit_time	score
1	1001	8001	2021-08-02 11:41:01	60
2	1002	8001	2021-09-02 19:30:01	50
3	1002	8001	2021-09-02 19:20:01	70
4	1002	8002	2021-09-02 19:38:01	70
5	1004	8001	2021-08-02 19:38:01	70
6	1004	8002	2021-08-02 19:48:01	90
7	1001	8002	2021-08-02 19:38:01	70
8	1004	8002	2021-08-02 19:48:01	90
9	1004	8002	2021-08-02 19:58:01	94
10	1004	8003	2021-08-02 19:38:01	70
11	1004	8003	2021-08-02 19:48:01	90
12	1004	8003	2021-08-01 19:38:01	80

请你找到高难度SQL试卷得分平均值大于80并且是7级的红名大佬，统计他们的2021年试卷总完成次数和题目总练习次数，只保留2021年有试卷完成记录的用户。结果按试卷完成数升序，按题目练习数降序。

示例数据输出如下：

uid	exam_cnt	question_cnt
1001	1	2
1003	2	0

解释：用户1001、1003、1004、1006满足高难度SQL试卷得分平均值大于80，但只有1001、1003是7级红名大佬；1001完成了1次试卷1001，练习了2次题目；1003完成了2次试卷9001、9002，未练习题目（因此计数为0）

with cte1 as(
    select uid
    from
    exam_record left join examination_info using(exam_id)
    left join user_info using(uid)
    where difficulty='hard' and tag='SQL' and level=7
    group by uid
    having avg(score)>80
),
cte2 as(
    select uid,count(exam_id) as exam_cnt
    from
    cte1 left join  exam_record using(uid)
    where left(submit_time,4)=2021
    group by uid
),
cte3 as(
    select uid,count(question_id) as question_cnt
    from
    cte1 left join practice_record using(uid)
    where date_format(submit_time,'%Y')=2021
    group by uid
)

select uid,exam_cnt,ifnull(question_cnt,0)
from
cte2 left join cte3 using(uid)
order by exam_cnt,question_cnt desc