I have an issue with returning data from the cube where attribute members are down as “Unknown”.
Background
Unknown values for my cube are defined at ETL stage. I have always defined my unknown values at ETL stage and have never experienced any problems thereafter. My dimension table is calleddimSurgeryPractice. Surrogate key for unknown Business Key is -1, and then I populate the remaining columns with values “Unknown” or -1 depending on whether they are numeric or varchar data type. Below is an illustration of what I mean.
SurgeryPracticeKey | SurgeryPracticeCode | Address Line 1 | City |
-1 | Unknown | Unknown | NULL |
Requirement
The business users want to know the number of patients who attended a given healthcare centre but did not register their Doctor's Practice against their details. In the SSIS Lookups the returned value for such is -1 given that no practice was registered.
Problem
It appears like when I browse the cube no count is returned against “Unknown” members, in this case (above illustration) for attribute [Surgery Practice].[Surgery Practice Code].&[Unknown]
or
[Surgery Practice].[Address Line 1].&[Unknown].
However, what’s surprising me is that I’m getting a count if I view data by attribute
[Surgery Practice].[City].&[].
As you can see in the illustration table above, I have deliberately not populated ColumnCity, which means that in the cube it shows as “Blank”. I’m failing to understand why I’m not getting any readings against members “Unknown” while I get readings in “Blank” when this row is all under one and the same key -1. Can someone please kindly help me about where I’m missing it? I hope that my question is clear.
Many thanks,
Mpumelelo