Max date on dimentionnal data

Hi cognos Experts!

I have a list of item, date and qty.
I would like a list of distinct item
and the max date corresponding to each item.
Easy to do on relational data with function ‘maximum’,
Not so on dimentionnal data.
Do you have an idea ?
thank you in advance.

here what i tried :


filter([Day],aggregate ([Purch - Qty Received] within set [Product Item]) is not null and aggregate ([Purch - Qty Received] within set [Branch (Product Item)]) <>0)