Have been using the Writeback facility in SSAS and wanted to understand the difference between the ROLAP Writeback and MOLAP Writeback.
My understanding is that ROLAP Writeback would allow you to update cell values for a measure group, which in turn update the cube and create a writeback table in the source database. This I have tested and works fine and the writeback table in the source database gives us the delta records of what has changed.
For MOLAP Writeback only updates the cube and does not create insert into the writeback table. I tested this and and it does not do what I expect. It updates the cube and inserts into the writeback table in the relational source just like the ROLAP Writeback.
So whats the difference ?