I want to include in the report all of the records whose date is between the parms startDate and endDate and any records that have an empty date field.
the formula I am using in the select expert is this:

({viewRequests.Date} <= {?EndDate} AND {viewRequests.Date} >= {?StartDate}) OR
{viewRequests.Date} <= Date (0 ,0 ,0) OR
isNull({viewRequests.Date})

but it doesn't show any records that have empty dates (They are being filtered out), But the records whose dates are between the parms are working fine. Please help me on this?