insert into exam_record (uid,exam_id,start_time,submit_time,score)
values
(1001,9001,'2021-09-01 22:11:12','2021-09-01 23:01:12',90),
(1002,9002,'2021-09-04 07:01:02',null,null)

插入数据格式：insert into 表 (属性) values(插入数据)