[Dimension].[All Hierarchies].[All] ?

As promised, question #2... ;)

As I mentioned in my previous post, my "real" case is a cube with 79 dimensions, most of which virtual, have been added for convenience.

Think for instance about a time dimension... Wouldn't it be nice to get a matrix with years horizontally, months vertically and displaying say the number of order you had for each cell in the resulting grid.
Ok, maybe you can do this with MDX but not in Excel, unless you create virtual dimensions for the Year and Month levels.

That's all good, but as it is, in my real case, I end up with four date dimensions for which I have to provide:

YQMD (Year, Quarter, Month & Day) hirarchized dimension
YWD (Year, Week, Day)
YQMD (Fiscal calendar)
Year
Quarter
Month
Week
Day (as 1, .. 31)
Week Day (for periodicity analysis over a week's time)
Date (as individual day - this is the backbone for the virtual dimensions)

It turns out this makes 40 dimensions by itself. For the sake of it, I grouped them by 4 hierarchies, although I've seen no specific functionality off of this in the data browser or Excel, so it really seems to be only for "show".

Now in my previous post I explained how I "spread" my session count to calculate a conversion rate. Given the number of dimensions I have (very high segmentation at the order level, very limited segmentation at the session/visit level), this means my calculated cell formula looks like this (hold your breath, it's ugly):

SubCube: {[Measures].[Session Count]}, DESCENDANTS([Business Unit].[All]), DESCENDANTS([Channel Source].[All]), DESCENDANTS([Currency].[All]), DESCENDANTS([FO Product Segment].[All]), DESCENDANTS([FO Quarter].[All]), DESCENDANTS([FO Value Segment].[All]), DESCENDANTS([Is Cancelled].[All]), DESCENDANTS([Is Customer Care].[All]), DESCENDANTS([Is Design Services].[All]), DESCENDANTS([Is Direct].[All]), DESCENDANTS([Is Estimated].[All]), DESCENDANTS([Is Holiday Order].[All]), DESCENDANTS([Is New].[All]), DESCENDANTS([Is Sales Services].[All]), DESCENDANTS([Language].[All]), DESCENDANTS([Payment].[All]), DESCENDANTS([Product Segment].[All]), DESCENDANTS([Value Segment].[All]), DESCENDANTS([FO Channel].[All]), DESCENDANTS([Reg Channel].[All]), DESCENDANTS([FCD].[Date].[All]), DESCENDANTS([FCD].[Day].[All]), DESCENDANTS([FCD].[Mth].[All]), DESCENDANTS([FCD].[Qtr].[All]), DESCENDANTS([FCD].[Wk].[All]), DESCENDANTS([FCD].[WkDay].[All]), DESCENDANTS([FCD].[Year].[All]), DESCENDANTS([FCD].[Fiscal].[All]), DESCENDANTS([FCD].[YMQD].[All]), DESCENDANTS([FCD].[YWD].[All]), DESCENDANTS([FRD].[Date].[All]), DESCENDANTS([FRD].[Day].[All]), DESCENDANTS([FRD].[Mth].[All]), DESCENDANTS([FRD].[Qtr].[All]), DESCENDANTS([FRD].[Wk].[All]), DESCENDANTS([FRD].[WkDay].[All]), DESCENDANTS([FRD].[Year].[All]), DESCENDANTS([FRD].[Fiscal].[All]), DESCENDANTS([FRD].[YQMD].[All]), DESCENDANTS([FRD].[YWD].[All]), DESCENDANTS([FSD].[Date].[All]), DESCENDANTS([FSD].[Day].[All]), DESCENDANTS([FSD].[Mth].[All]), DESCENDANTS([FSD].[Qtr].[All]), DESCENDANTS([FSD].[Wk].[All]), DESCENDANTS([FSD].[WkDay].[All]), DESCENDANTS([FSD].[Year].[All]), DESCENDANTS([FSD].[Fiscal].[All]), DESCENDANTS([FSD].[YQMD].[All]), DESCENDANTS([FSD].[YWD].[All])

Caculation Value: CalculationPassValue(([Business Unit].[All],[Channel Source].[All],[Currency].[All],[FO Product Segment].[All],[FO Quarter].[All],[FO Value Segment].[All],[Is Cancelled].[All],[Is Customer Care].[All],[Is Design Services].[All],[Is Direct].[All],[Is Estimated].[All],[Is Holiday Order].[All],[Is New].[All],[Is Sales Services].[All],[Language].[All],[Payment].[All],[Product Segment].[All],[Value Segment].[All],[FO Channel].[All],[Reg Channel].[All],[FCD].[Date].[All],[FCD].[Day].[All],[FCD].[Mth].[All],[FCD].[Qtr].[All],[FCD].[Wk].[All],[FCD].[WkDay].[All],[FCD].[Year].[All],[FCD].[Fiscal].[All],[FCD].[YMQD].[All],[FCD].[YWD].[All],[FRD].[Date].[All],[FRD].[Day].[All],[FRD].[Mth].[All],[FRD].[Qtr].[All],[FRD].[Wk].[All],[FRD].[WkDay].[All],[FRD].[Year].[All],[FRD].[Fiscal].[All],[FRD].[YQMD].[All],[FRD].[YWD].[All],[FSD].[Date].[All],[FSD].[Day].[All],[FSD].[Mth].[All],[FSD].[Qtr].[All],[FSD].[Wk].[All],[FSD].[WkDay].[All],[FSD].[Year].[All],[FSD].[Fiscal].[All],[FSD].[YQMD].[All],[FSD].[YWD].[All],[Measures].[Session Count]), 0)

If you read all this, you can see already the cryptic dimension names like "FRD", "FSD" and so forth... that's because with the real names ("First Refund Date", "First Ship Date", the query processor errored out... visibly there is a limit in the size of the formulas you can post!

Is there no other way to achieve this result? Basically I mean to say: if the session count is not defined at your level along this dimension, go to the root of the dimension to get the value there, this along a slew of dimensions, many of which are inherently dependent because of the usage of virtual dimensions (therefore if I wish to go to the root of my "First Refund Date" for instance, I wish to do so along all sub-dimensions... Heck, as far as I'm concerned this is conceptually only ONE dimension, just with various views upon it...

Using hierachies I was sort of hoping for the ability to have something like:
[FRD].[All Hierachies].[All]

Am I just asking for too much or do I just not know (quite probable) the magic keyword that can do this?

Where this is becoming quite critical is that I actually have a calculated cell that goes as follows (abridged):

SubCube: similar as before

Calculation: [Measures].[Order Count]*CalculationPassValue((...set of all un-tied dimension roots..., [Measures].[Distributed Marketing Cost])/CalculationPassValue((...set of all un-tied dimension roots..., [Measures].[Order Count])

Now the purpose of this is to distribute external costs at the order level. In short, say that you know you spent $10,000 globally promoting a specific group of websites in commission money (you pay $1 for each order). This formula allows me to get that a specific website, with 20 orders incurred an additional marketing cost of $20. That's actually the object of my next thread's question (spreading a multiplication through the aggregations)

For the purpose of this thread I am just concerned about the size of my formulas. Renaming the dimensions seemed to "buy" me some margin and I was actually quite surprised to find that the formula still fitted in, and works, but it is only a matter of time until I have to add more dimensions and the whole thing blows up in my face. Adittionally this is obviously not pleasant to look at and maintain.

Any better solution?

Thanks,

Seb