I'm assuming you want an inclusive search, i.e.
Start Date - 11/21/2006
End Date - 11/21/2007
returns rows where date is 11/21/2006 AND rows where date is 11/21/2007 (plus everything in between, obviously).
Code:
where deptDate >= start_date and deptDate < end_date
Note the different operators here: >= and <
To avoid the time issue, start_date should be midnight on the start day of the search, end_date should be midnight on the _day after_ the end date.
e.g. for the following
Start Date - 11/21/2006
End Date - 11/21/2007
Code:
where deptDate >= 11/21/2006 00:00:00 and deptDate < 11/22/2007 00:00:00
Note end date set to 11/*22*/2007