Quiz result statistics:
测验结果统计:
UserId StartDate EndDate UserScore
1 2015-03-04 14:01:26 2015-03-04 14:02:14 200
2 2015-03-04 14:01:26 2015-03-04 14:02:14 180
3 2015-03-04 13:42:23 2015-03-04 13:43:19 200
4 2015-03-04 13:07:52 2015-03-04 13:08:57 160
UserId Star
