on a form, have the dates for the current data:
txtStartDate, txtEndDate
and the prev data (these can be hidden if you want):
txtPrevStart, txtPrevEnd
when the current is entered, the afterupdate event can fill in the previous datas
Code:
sub txtStartDate_Afterupdate()
txtPrevStart = DateAdd("d",-6,txtStartDate)
end sub
sub txtEndDate_Afterupdate()
txtPrevEnd = DateAdd("d",-6,txtEndDate)
end sub
then the query can use these
query qsCurrent:
select * from table where [date] between forms!myForm!txtStartDate and forms!myForm!txtEndDate
query qsPrev:
select * from table where [date] between forms!myForm!txtPrevStart and forms!myForm!txtPrevEnd
then you can put both queries together in a union query.