DATA WAREHOUSING FUNDAMENTALS: A Comprehensive Guide for IT Professionals

6.2. DATA DESIGN

In the data design phase, you come up with the data model for the following data repositories:

• The staging area where you transform, cleanse, and integrate the data from the source systems in preparation for loading into the data warehouse repository

• The data warehouse repository itself

If you are adopting the practical approach of building your data warehouse as a conglomeration of conformed data marts, your data model at this point will consist of the dimensional data model for your first set of data marts. On the other hand, your company may decide to build the large corporate-wide data warehouse first along with the initial data mart fed by the large data warehouse. In this case, your data model will include both the model for the large data warehouse and the data model for the initial data mart.

These data models will form the blueprint for the physical design and implementation of the data repositories. You will be using these models for communicating among the team members on what data elements will be available in the data warehouse and how they will all fit together. You will be walking through these data models with the users to inform them of the data content and the data relationships. The data models for individual data marts playa strong and useful role in communication with the users.

Which portions of the requirements definition drive the data design? To understand the impact of requirements on data design, imagine the data model as a pyramid of ...