一个表train 中,
车序  时间                    cc 
1    2008-12-12 00:00:01   a
2    2008-12-12 00:00:01   a
3    2008-12-12 00:00:01   a
4    2008-12-12 00:00:01   a
5    2008-12-12 00:00:01   a
1    2008-12-12 00:10:01   b
2    2008-12-12 00:10:01   b
3    2008-12-12 00:10:01   b
4    2008-12-12 00:10:01   b
1    2008-12-12 00:10:11   c
2    2008-12-12 00:10:11   c
3    2008-12-12 00:10:11   c
要得到的结果:
时间                    cc   条数
2008-12-12 00:00:01   a   5
2008-12-12 00:10:01   b   4
2008-12-12 00:10:11   c   3要在一条SQL语句里实现,求解!!!