How to re-create CUBE and not corrupt reports based on CUBE

Question

Hi,
We are using a prototyping approach to releasing CUBEs to our users as they only tend to understand what they want after playing with the tool a bit, this has meant that additional requirements sometime require another dimension for eg.
This can't be added to a CUBE so we have to delete and re-create the CUBE.
The issue is that users have developed spreadsheets against these CUBEs that get corrupted if they CUBE is deleted and re-created. So , what is the way forward for incorporating user requirements into an existing CUBE, does a change to the design require all reports/spreadsheets to be re-written or is there some trick that will retain the links to pre-existing reports.
BTW , am using 10.2.0.2 AWM and DB.
Thanks for any assistance,
Brandon

Answer 1

As long as the dimensionality of the cube has the same contents (even if it is in a different order), the reports will continue to work in my experience. If you add a new dimension, the report doesn't have a selection set up for that dimension and therefore is now invalid and all reports must be recreated against that cube. Adding new levels above the leaf level of your dimensions and adding new measures should not corrupt their reports.
I would suspect after a few iterations of losing their reports, your users will learn to test and specify their needs more completely to ensure they have all of the required dimensions.
Alternatively, you can set up one cube that only consists of calculated measures that has ALL of the dimensions of your AW. Create calculated measures that then point to these other cubes which may not have all of the dimensions. In this case, the report is using the "calculated" measures whose dimensionality does not change even if you add a dimension to one of the underlying cubes.
For example, if you have Time, Customer, Product, and Geography in your AW, but you choose to only have Time and Product in a cube called YEAR_ITEM_PLAN that holds your targets for the year, and they later decide to do their plans Time, Product and Gegoraphy, you could recreate the YEAR_ITEM_PLAN cube to include Geography and as long as the calculated members cube you created earlier always had geography, their reports should continue to function.