Business Model and Mapping Layer (BMM Layer)
BMM Layer is a metadata layer within the BI metadata.
BI metadata is defined by the BI metadata designers (or called the BI architect).
BMM layer is the semantic layer to hide the physical data model from the BI users. It exposes the information model to the business users.
Although BI platform does not force the BI metadata designer to identify the logical tables as dimension or fact tables, typically, the BMM layer object design follow dimension modeling. The mapping between the physical layer and the BMM layer facilitates the relational to dimensional mapping.