date range in qv9

[#1]

to start forgiveness for my English

I Have a and b

a
date register	cant	month	proyect
27/02/2009	1	febrero	a
01/02/2009	2	febrero	a
02/02/2009	3	febrero	a
15/02/2009	4	febrero	a
b
proyect	date manufacturing	date order	month
a	15/02/2009	28/02/2009	febrero

I am experiencing daily table 1 because I wanted only appear when filtering records which register date <= date manufacturing, according to a project

[#2]

sum( {$< [date start] =[date manufacturing]>} cantidad)

but,not just which are the same, but all from the first date and that date is equal to the manufacturinf, the whole range, eg in this case the sum would be 9, which would result from adding the number of the day 1, day 2 and day 15

[#3]

someone understands me, please????