Fig. 14.1.11 The star join and data marts.The source of data for the star join is the corporate data model. Even though the star join
reflects a particular customized view of data, the source of the data is uniform. The
source of the data is still the single source of truth for the corporation.
It is noteworthy that it is possible to build a data mart whose source of data is not the data
warehouse. While such a structure can be built, it is outside the boundaries of the end-
state architecture. Building a data mart whose source of data is not the data warehouse is
like violating the zoning codes of a city. You could build a hovel next to a large office
building. But if you do, you will have a poorly planned city. And there are a whole host
of other problems that come with having a poorly planned city.
Fig. 14.1.12 shows that star join environment is fed from the corporate data model.
Chapter 14.1: Data Models Across the End-State Architecture