A caution on using Dimensional DSVs in Data Mining

If you are using a dimensional-style DSV in a Data Mining project, such as below:
b

Fig 1: A Dimensional DSV

Be aware that if you include a column from a Dimension table in your Mining Structure, the model will actually identify each key entry on the source table as a distinct value, rather than each distinct value in the Dimension table. I found this out because I added a grouping category to one of my dimensional tables – a simple high – medium – low group – and there were multiple values in the attribute states for each grouping, as below:

b

Fig 2: Mining Legend

To work around this you will need to add a Named Calculation to get the group on the main table, or convert the main table to a Named Query.

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  1. [...] a followup to this post I have found that not only does using a table external to the one being mined to provide a grouping [...]



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