Actually the question is not trivial at all. The problem is quite interesting and many have troubles discovering what needs to be done.

Here is what you do:
1. Go to the Cube editor
2. Click your virtual dimension
3. Change Aggregation Usage property from Standard to Custom.

That would assure that storage design wizard for this cube only will desing Aggregations taking into account virtual dimension.

If you are using this dimension in several cubes, you will have to repeat the procedure for every cube.

HTH

P.S. Apologies for writing English. Haven’t used Russian keyboard for awhile.

Edward
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