I have a multi level dimension of which the leaf level is a policy
reference. Within the Fact table these references may be duplicated
across months, but I would like to create a calculated measure which
counts the number of policy references ignoring these duplications.
I cannot seem to get DistinctCount to work, it gives incorrect counts
(too high) when I try
DistinctCount({[Policy].[NewCOB].[Polid].Members}) - does anyone have
any experience with this function or suggestions please?
Thank you
Rachel

Sorry I forgot to say that the incorrect counts are because the
calculated measure is in a virtual cube comprising 2 other cubes, which
both have fact tables containing these references so they are being
counted from both, I think.
If I try that DistinctCount MDX on the first cube only, it works
correctly as a calculated measure, but I cannot bring that through to
the virtual cube.
I considered using a calculated cell to create an ordinary measure on
the fly, but when I tried it I got an error saying DistinctCount can
only be used at the top level - although the same code works as a
calculated measure??