i want to calculate how much time each employee sending outside of the company in day wise (no replies)

empcode emp_code_name time in_out date
0031 ASHWINI O 08:12:27 Entry 2010-09-14
0031 ASHWINI O 08:48:04 Exit 2010-09-14
0031 ASHWINI O 09:04:39 Entry 2010-09-14
0031 ASHWINI O 11:42:40 Exit 2010-09-14
0031 ASHWINI O 11:55:49 Entry 2010-09-14
0031 ASHWINI O 13:07:43 Exit 2010-09-14
0031 ASHWINI O 13:42:47 Entry 2010-09-14
0031 ASHWINI O 15:56:29 Exit 2010-09-14
0031 ASHWINI O 16:14:28 Entry 2010-09-14
0031 ASHWINI O 17:10:50 Exit 2010-09-14
0025 METHI LATA 08:16:45 Entry 2010-09-14
0025 METHI LATA 08:31:24 Exit 2010-09-14
0025 METHI LATA 09:04:39 Entry 2010-09-14
0025 METHI LATA 11:42:20 Exit 2010-09-14
0025 METHI LATA 11:55:54 Entry 2010-09-14
0025 METHI LATA 13:22:11 Exit 2010-09-14
0025 METHI LATA 13:42:49 Entry 2010-09-14
0025 METHI LATA 16:00:51 Exit 2010-09-14
0025 METHI LATA 16:14:09 Entry 2010-09-14
0025 METHI LATA 17:59:27 Exit 2010-09-14
this is my table
in this i want to calculate "exit time" minus "entry time" for each user date wise please help me