It may be another way of doing this
I would like to be able to evaluate on a flag that is sent by an interface to determine to filter by a date or not to filter by a date by using the case when
where emp_assignment_status = 'ACTIVE'
and emp_dept like '%MTN%'
-- determine if I should filter by date or not
case in_flag -- parameter valuse passed from a java inteface
when 'on' then
emp_eoas > to_date('01/01/2012','MM/DD/YYYY')
when 'off' then
-- do not filter by date