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Legacy Business Intelligence => COGNOS PowerPlay => Topic started by: jguevin on 25 Oct 2006 01:36:33 PM

Title: Ideal Number of Categories in a Dimension built in transformer
Post by: jguevin on 25 Oct 2006 01:36:33 PM
Does anyone know the "best practice" for number of categories in a dimension when building a model in Transformer?

Thanks
Jeff
Title: Re: Ideal Number of Categories in a Dimension built in transformer
Post by: srikalyan on 27 Oct 2006 02:08:21 PM
maximum no. of categories allowed are 65536.
Title: Re: Ideal Number of Categories in a Dimension built in transformer
Post by: Opher on 28 Nov 2006 03:26:32 PM
Well, I'm not 100% certain, and don't have the time right now to run a test, but I believe the reply is incomplete.  The limit of 65536 categories is for child categories, not for the whole Dimension.  For an entire Dimension, I think the limit is closer to 2,000,000.

Going back to the original poster, best practice in designing a Dimension is to have 7-10 categories at the top level and then a 10:1 ratio on each level, so with 10 at the top level, 100 at the second, 1000 at the third, etc.  Transformer will produce a warning message if a single branch gets too many of the child categories.

Good luck,
Opher
Title: Re: Ideal Number of Categories in a Dimension built in transformer
Post by: Darek on 06 Dec 2006 07:56:48 AM
There is no physical limit on the # of categories. There is a "supportable" or "making sense" limit of 2M you've mentioned.

And you can override the warning, meaning, increase the number of allowable child categories before a warning is issued.