How to Merge Related Dimensions into a Single Dimension 1

[VishalSingh]

Hi Folks,
We all have heard that if we have Data Source Query Subjects like Product line, Product Type and Product Name we can merge them together and have one Query Subject called Product which we can connect to a Fact like Order. My questions is how exactly is this done?
Do we in one namespace connect Product Line, Product Type and Product Name using a Product Id, and then Use a Model Query Subject and bring them together and use this model query subject to create the join to the Fact?

Any help would be greatly appreciated.

Thanks,
Vishal

 

[blom0344]

From your description it sounds like you are looking for reducing a snowflake to a star. This is done by combining the snowflake objects into one new model query subject and then using the id of the lowest grain level to the fact.
I assume that this - in your case - is the productID.
The productID is used as the basis , then use 2 joins to ProductLine and ProductType to add attributes of these dimensions to the ProductID.
Be careful with the joins, if for some productID's no lines/types are defined you need to use outerjoins and substitute a value for the missing attribute (like N/A)

Ties Blom