Adding a calculated column that has distinct values

[White light]

Hi Everyone,

Need to add H1/H2(half year 1 and half year 2) as a new dimension in Analysis studio Cube.

I am trying to define calculation in Framework manager for below condition.

Condition:
If a store purchases one product in Q1 then sale=1 and if same store purchases same product in Q2, the sale for Q2 must not be included. so sale must be =1 for H1(or Q1+Q2)

I am trying to get distinct combination of storeid || productid for months between 1 and 6 to achieve this. However, distinct is not working since it is grouping up and summarizing.

Reports are being used as source for this cube.
Is there a way to achieve this calculation(or requirement) in Framework manager or Query studio?
any input/ideas would be appreciated.

Thanks,
WL