Anybody ever used the "Define Member Sets" property in queries?
I know they are used when converting an Analysis to a Report but I can't understand very well from the documentation what that is useful for.
Yes. They are vital when authoring a Report from a Dimensional data source and various drill-down/up challenges are presented when separate levels are employed in the report and they need to follow a drill properly on either/any level.
They're also helpful to make sure that set expressions aggregate correctly across multiple measures.
E.g.
Multiple measures
Account1 a, b, c
Account2 a, b ,c
accountset(account1, account2) = a+a, b+b, c+c
The last row didn't work for me until I made a Member Set (which I labelled MS accountset, arbitrarily).
Then, this worked: aggregate(currentMeasure within set [MS accountset])
The only tricky thing there is that even though you'll have the Member Set, I couldn't see a way to drag it into the data item... so I dragged [accountset] and edited to add the MS.
A bit late but. Thank you.