A
Role-Playing Dimension is a Dimension which is connected to the same
Fact Table multiple times using different Foreign Keys. This helps the
users to visualize the same cube data in different contexts/angles to
get a better understanding and make better decisions.
Example:-
Consider a Time Dimension which is joined to the same Fact
Table (Say FactSales) multiple times, each time using a different
Foreign Key in the Fact Table like Order Date, Due Date, Ship Date,
Delivery Date, etc. Essentially there is only one single physical
dimension called Date Dimension. However, it is joined multiple times to
the Fact Table to help the users to visualize the cube data in the
context of different dates.
Here are some highlights of a Role-Playing Dimension:
It is a single physical Dimension Table.
Same Dimension Table connects to the same Fact Table multiple times using different Foreign Keys from the Fact Table.
When a Role-Playing Dimension is added to the cube, it appears as a
different dimension (one instance for each Foreign Key to which it is
joined) to the end users and hence playing multiple roles.
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