Fundamental Relational Concepts

Every data-modeling technique has its own set of terms, definitions, and techniques. This vernacular permits us to understand complex and difficult concepts and to use them to design complex databases. This book applies relational data-modeling techniques for developing the data warehouse data model. To that end, this chapter introduces the terms and terminology of relational data modeling. It then continues with an overview of normalization techniques and the rules for the different normalization levels (for example, first, second, and third normal form) and the purpose for each. Sample data models will be given, showing the progression of normalization. The chapter ends with a discussion of normalization of the data model and the associated benefits. Before we get into the various types of data models we use in creating a data warehouse, it is necessary to first understand why a data model is important and the various types of data models you will create in developing your BI environment.