How to represent the start and end times for one day?
Using October 23, 2008 as an example, is it start 2008-10-23 12:00:00 AM and end 2008-10-23 11:59:59 PM?
Your notation is strange. I'd suggest the standard way of specifying a full day range is:
2008-10-23 00:00:00 and finish 2008-10-23 23:59:59