我有以这种格式出现的出勤数据:
EmployeeId | Date | Time |
--------------------------------------
1 | 01/01/2015 | 14:01:35 |
2 | 01/01/2015 | 13:00:00 |
1 | 01/01/2015 | 17:35:37 |
1 | 01/01/2015 | 18:01:35 |
2 | 01/01/2015 | 19:14:12 |
1 | 01/02/2015 | 14:21:42 |
2 | 01/02/2015 | 15:12:03 |
1 | 01/02/2015 | 15:42:20 |
我需要以下格式的数据:
EmployeeId | Date | FirstTime | LastTime |
--------------------------------------------------
1 | 01/01/2015 | 14:01:35 | 18:01:35 |
2 | 01/01/2015 | 13:00:00 | …