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IBM Cognos 8 Platform => COGNOS 8 => BI Modeling (Transformer) => Topic started by: dssd on 21 Nov 2012 12:29:53 PM

Title: Number of Cubes
Post by: dssd on 21 Nov 2012 12:29:53 PM
I need to determine the number of cubes that i need to use.....I have the below scenario where i have 4 subject areas which deal with different areas of the same business. I have total 5 dimensions...all of which are not applicable to each subject area. Should i have

5 different cubes with 5 different models
5 different cubes with 1 model but exclude a dimension while building the cube? Which is better and why?
Title: Re: Number of Cubes
Post by: dssd on 25 Nov 2012 07:33:34 AM
Could anyone share their views
Title: Re: Number of Cubes
Post by: tjohnson3050 on 25 Nov 2012 08:17:28 AM
If most of the dimensions are shared across subject areas, I would use one model.
Title: Re: Number of Cubes
Post by: dssd on 25 Nov 2012 11:07:43 AM
Scenario is something like below

             SArea1      SArea2      SArea3    SArea4
Dim 1       X                X                X             X
Dim 2       X                X                X             X
Dim 3                         X
Dim 4      X
Dim 5                                           X

How many Models? How many cubes should we build?
Title: Re: Number of Cubes
Post by: tjohnson3050 on 25 Nov 2012 03:09:28 PM
If you want to report on the subject areas together, and cube size is not an issue, then build one model and one cube.

Title: Re: Number of Cubes
Post by: MFGF on 26 Nov 2012 05:57:55 AM
It also depends on whether people from one area of the business would be confused by seeing information from another subject area. As tjohnson3050 says, either build a single cube if this is not an issue, or build separate cubes for each subject area from a single model. If you create separate models, you will end up modelling the dimensions multiple times, and you run the risk of modelling them slightly differently, plus you will be repeating the same work over and over.

MF.
Title: Re: Number of Cubes
Post by: cognostechie on 27 Nov 2012 10:17:01 AM
You could also build just one cube and set security on the subject areas by different user groups (if the users need to see only their subject area)
Title: Re: Number of Cubes
Post by: bdbits on 27 Nov 2012 03:22:32 PM
And to add to the numerous choices before you... :-)

You can build one Transformer model, then create different cubes within the one model. You can select which dimensions and measures are included/excluded in the properties for the cube. This has the benefit of one model, but a simplified user experience.
Title: Re: Number of Cubes
Post by: dssd on 06 Dec 2012 02:40:33 PM
Can i exclude a level from a cube like i can exclude a dimension. Time dimension is uptil Day but now i want my cube to only have until Month but keep the model as the same. Is it possible?
Title: Re: Number of Cubes
Post by: tjohnson3050 on 06 Dec 2012 08:16:02 PM
You can create multiple hierarchies with different levels within a dimension.  Go to view - categories.
Title: Re: Number of Cubes
Post by: dssd on 09 Dec 2012 10:19:50 PM
Thanks. Are there any maintenance issues associated with it. Would i loose the views if i clean house