DrID(int identity)  StartTime(DateTime)             EndTime(DateTime)
    1                3/31/2009 8:00:00 AM   3/31/2009 10:30:00 AM

SlotID   SlotStartTime(varchar)   SlotEndTime(varchar)
1         8:00AM                      8:15AM
2         8:15AM                      8:30AM
3         8:30AM                     8:45AM

DrID    StartTime             EndTime              DateOfAllocation
1       4/5/2009 8:00:00 AM   4/5/2009 9:30:00 AM   4/5/2009 12:00:00 AM
2       4/12/2009 8:00:00 AM  4/12/2009 9:30:00 AM  4/12/2009 12:00:00 AM
likewise

AppointmentID    SlotID  AppointmentDate
1                1        4/5/2009
2                3        4/12/2009