Parent-child dimension

I'm trying to connect a parent-child dimension to my fact table.
I would like to browse cube measure (sold items quantity) through the
dimension "Groups" representing items family (tree structure).
Here are the tables:
Fact table (items sold with quantity):
--
IdItem;Quantity
1;5
2;2
3;1
1;6
3;8
--
Dimension table (parent-child tree representing groups item):
--
IdGroup;GroupName;IdParent;IdItem
1;AAA;-1;-1
2;BBB;1;-1
3;CCC;1;-1
4;O1;2;1
5;O2;2;2
6;O3;3;3
--
If I connect dimension to fact table with a regular relation (on IdItem
attribute of each table) and browse cube, I obtain for each node the
same quantity (22)
AAA (22)
-BBB (22)
--O1 (22)
--O2 (22)
-CCC (22)
--O3 (22)
I would like to obtain this result:
AAA (22)
-BBB (13)
--O1 (11)
--O2 (2)
-CCC (9)
--O3 (9)
If I use a "reference relation" with a middle table it's ok...
but I don't understand the difference!!!!!!
Can someone help me?
thanksOoops! I'm using Analysis Services 2005 :-)

> I'm trying to connect a parent-child dimension to my fact table.
> I would like to browse cube measure (sold items quantity) through the
> dimension "Groups" representing items family (tree structure).
> Here are the tables:
> Fact table (items sold with quantity):
> --
> IdItem;Quantity
> 1;5
> 2;2
> 3;1
> 1;6
> 3;8
> --
> Dimension table (parent-child tree representing groups item):
> --
> IdGroup;GroupName;IdParent;IdItem
> 1;AAA;-1;-1
> 2;BBB;1;-1
> 3;CCC;1;-1
> 4;O1;2;1
> 5;O2;2;2
> 6;O3;3;3
> --
> If I connect dimension to fact table with a regular relation (on IdItem
> attribute of each table) and browse cube, I obtain for each node the
> same quantity (22)
> AAA (22)
> -BBB (22)
> --O1 (22)
> --O2 (22)
> -CCC (22)
> --O3 (22)
> I would like to obtain this result:
> AAA (22)
> -BBB (13)
> --O1 (11)
> --O2 (2)
> -CCC (9)
> --O3 (9)
> If I use a "reference relation" with a middle table it's ok...
> but I don't understand the difference!!!!!!
> Can someone help me?
> thanks