I am not experienced with cube data sources, but here are two options that may be worth trying:
- create a Set from your fields "Fact" and "Unit of Measure"
- create a calculated field that concatenates those two text fields together, this provides you control over the formatting to the combined text values.
Both of these are done in the attached.
Why do cubes not allow calculations using dimensions? - seems like a major loss of functinoality to me!
A loss of functionality indeed. :-) I think it comes down to philosophy - the point of cubes is that they pre-calculate things for you, so those things are really fast, but don't allow you to do other things (which might be slow).
Unfortunatley it also means it's difficult to get your head around the tutorials. I can't seem to work around that aspect when it comes to trying all the cool stuff i'm seeing.