Conditional Sum... dynamic Date range MDX

Question

Hi
i had question just now and got the right answer for it. That was great. However, I ran and the result was not right.
It turned out I can not just sum up sales from the current date to the last date of sales but add one extra condition.
I have three dimensions: Invoice Date, Licence Start Date, Licence End date. I need to add a condition saying only sales with licence start date is equal or early than current licence end date for the below query.
I am looking at Filter function in MDX book right now. ahh It's been too long since I used the MDX last time. This is kinda urgent. Any help would be appreciated.
I have added the condition as follows. It is not right because I got the same result as the first one. It should be less.
And I think it's because the current member of licence start date for the expired month invoices are not applied right. 
With member MEASURES.ActiveLicences as 
sum ( 
Filter(
{[License Expiry Date].[FinancialYear].CurrentMember: null },
([Licence Start Date].[Financial_Year].CurrentMember <= [License Expiry Date].[FinancialYear].CurrentMember)
[Measures].[No of Students]
select {
MEASURES.ActiveLicences,
[Measures].[No of Students] } on columns, 
[License Expiry Date].[FinancialYear].[YY-MMM].members on rows 
from [Sales];
from 
With member MEASURES.ActiveLicences as 
sum ( 
{[License Expiry Date].[FinancialYear].CurrentMember: null },
[Measures].[No of Students]
select {
MEASURES.ActiveLicences,
[Measures].[No of Students] } on columns, 
[License Expiry Date].[FinancialYear].[YY-MMM].members on rows 
from [Sales];
Kind regards

Answer 1

Hi Sqlma,
According to your description, you are going to sum the measure for the members with the dondition that licence start date is equal or early than current licence end date for the below query, right?
In this case, you need filter out the members that licence start date is equal or early than current licence end date for the below query. And then sum the total measures using sum function. I have tested it on my local environment, here is a sample query
for you reference.
with set [aa]
as
filter
([Product].[Product Categories].members,
[Measures].[Internet Sales Amount]>30000)
member [measures].[b]
as
sum([aa],[Measures].[Internet Sales Amount])
select {[Measures].[Internet Sales Amount],[measures].[b]} on 0,
[aa] on 1
from [Adventure Works]
where [Date].[Calendar].[Calendar Year].&[2008]
Regards,
Charlie Liao
TechNet Community Support