How to model header vs. line item data
My data source differentiates header and line item data that are of different granulation.The header data has two key figures on an aggregated level. The line-item data has complementing kex figures on a more detailed level.
How would I model this in BW? Would I create two cubes (one for header and one for line item data)? And for reporting purposes I would combine them into a multiprovider? Or which way would I choose?
Yes it is possible,
Just when mapping the keyfigures of the update rule that doesn't have line item, in the mapping of the line item choose (if it is not already chosen by default) the "inital value" option.
My solution is a possible solution, you can simple create a single InfoCube that has related data and is feed by two sources, taht's why the same InfoCube. Off course you could also create two cubes and one multicube, although in this case you're having 3 InfoProviders instead of 1. Also having separate InfoCubes might be helpful if you really want to separate data at any point. If you always want to see data from both header and line item why not only one InfoProvider and one place to keep and maintain data. The cons in this case you could have a lot of data in only one cube, rather than separate data in two cubes.
But I guess this is ways of perspective.