Data aggregation: which solution for this case ?

Question

Hi all,
I have a fact table where measures are referred to a single year. Outlining, something like this:
year quantity
1998 30
1998 20
2000 70
2001 20
2001 20
I would to build a cube and then to analyze "tot.quantity for each year" but don't want aggregate "tot.quantity for all year".
I haven't in my source database the "Year dimension" to mapping on year field.
Do you have some suggestions on how to implement this and how to build cube using AWM tools (Year dimension and relative levels/hierarchies)?
thanks.

Answer 1

I am not sure I fully understand what you are trying to do, but from the example below you could create a single dimension called Year with one level of Year, add a hierarchy containing only one level, create a cube dimensioned by year and then map the table you have described below to the cube. As there is only one level in the dimension, no aggregation would performed by AWM.
For the mapping you will need to create a view over your source table as follows:
CREATE VIEW FACT_VIEW AS SELECT, YEAR, SUM(QUANTITY) FROM TABLE GROUP BY YEAR
because AWM does not support an additive data loading model (surprisingly the API actually does but this is not exposed in AWM). You can only provide a single row for each dimension member. If you present multiple rows then the last row wins which in your example would result in the following data being loaded into AWM:
1998 20
2000 70
2001 20
If you create the view as shown above you should get the following data loaded:
1998 50
2000 70
2001 40
which is what I think you want?
Hope this helps
Keith Laker
Oracle EMEA Consulting
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