table stores all records as a snapshot (in time) ... not just records to show on the report.  A good command of OBIEE requires understanding physical data structures to optimize the whole user experience.

You introduce a new element: domain ... that obviously has to be part of the snapshot data

Database has the most horsepower to do data manipulation -- use it to it's potential

BI Logic Layer has flexibility, but not as much power for data manipulation -- use it wisely for hierarchical traversing, drilling, calculated and time-series measures

BI Presentation layer has most flexibility and next to no power for data manipulation - use it for it's intended design; to present the story from the data