有一个试卷作答记录表exam_record,请从中统计出总作答次数total_pv、试卷已完成作答数complete_pv、已完成的试卷数complete_exam_cnt。
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 | 1001 | 9001 | 2021-05-02 10:01:01 | 2021-05-02 10:30:01 | 81 |
3 | 1001 | 9001 | 2021-06-02 19:01:01 | 2021-06-02 19:31:01 | 84 |
4 | 1001 | 9002 | 2021-09-05 19:01:01 | 2021-09-05 19:40:01 | 89 |
5 | 1001 | 9001 | 2021-09-02 12:01:01 |