请从试卷作答记录表中找到SQL试卷得分不小于该类试卷平均得分的用户最低得分。
示例数据 exam_record表(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 | 2020-01-02 09:01:01 | 2020-01-02 09:21:01 | 80 |
2 | 1002 | 9001 | 2021-09-05 19:01:01 | 2021-09-05 19:40:01 | 89 |
3 | 1002 | 9002 | 2021-09-02 12:01:01 | (NULL) | (NULL) |
4 | 1002 | 9003 | 2021-09-01 12:01:01 | (NULL) | (NULL) |
5 | 1002 | 9001 | 2021-02-02 19:01:01 | 2021-02-02 19:30:01 | 87 |
6 | 1002 | 9002 | 2021-05-05 18:01:01 | 2021-05-05 18:59:02 | 90 |
7 | 1003 | 9002 | 2021-02-06 12:01:01 | (NULL) | (NULL) |
8 | 1003 | 9003 | 2021-09-07 10:01:01 | 2021-09-07 10:31:01 | 86 |
9 | 1004 | 9003 | 2021-09-06 12:01:01 | (NULL) | (NULL) |
examination_info表(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 | 2020-01-01 10:00:00 |
2 | 9002 | SQL | easy | 60 | 2020-02-01 10:00:00 |
3 | 9003 | 算法 | medium | 80 | 2020-08-02 10:00:00 |
示例输出数据:
min_score_over_avg |
87 |
解释:试卷9001和9002为SQL类别,作答这两份试卷的得分有[80,89,87,90],平均分为86.5,不小于平均分的最小分数为87
示例1
输入
drop table if exists examination_info; CREATE TABLE examination_info ( id int PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID', exam_id int UNIQUE NOT NULL COMMENT '试卷ID', tag varchar(32) COMMENT '类别标签', difficulty varchar(8) COMMENT '难度', duration int NOT NULL COMMENT '时长', release_time datetime COMMENT '发布时间' )CHARACTER SET utf8 COLLATE utf8_general_ci; drop table if exists exam_record; CREATE TABLE exam_record ( id int PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID', uid int NOT NULL COMMENT '用户ID', exam_id int NOT NULL COMMENT '试卷ID', start_time datetime NOT NULL COMMENT '开始时间', submit_time datetime COMMENT '提交时间', score tinyint COMMENT '得分' )CHARACTER SET utf8 COLLATE utf8_general_ci; INSERT INTO examination_info(exam_id,tag,difficulty,duration,release_time) VALUES (9001, 'SQL', 'hard', 60, '2020-01-01 10:00:00'), (9002, 'SQL', 'easy', 60, '2020-02-01 10:00:00'), (9003, '算法', 'medium', 80, '2020-08-02 10:00:00'); INSERT INTO exam_record(uid,exam_id,start_time,submit_time,score) VALUES (1001, 9001, '2020-01-02 09:01:01', '2020-01-02 09:21:01', 80), (1002, 9001, '2021-09-05 19:01:01', '2021-09-05 19:40:01', 89), (1002, 9002, '2021-09-02 12:01:01', null, null), (1002, 9003, '2021-09-01 12:01:01', null, null), (1002, 9001, '2021-02-02 19:01:01', '2021-02-02 19:30:01', 87), (1002, 9002, '2021-05-05 18:01:01', '2021-05-05 18:59:02', 90), (1003, 9002, '2021-02-06 12:01:01', null, null), (1003, 9003, '2021-09-07 10:01:01', '2021-09-07 10:31:01', 86), (1004, 9003, '2021-09-06 12:01:01', null, null);
输出
87
备注:
保证至少有一个有效的SQL类别的试卷作答分数