Database Reference
In-Depth Information
Chapter 3
Table Normalization and
Windows Azure SQL Database
Objectives
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Learn in detail about database tables
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Identify problems in table structures
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Normalize tables
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Convert a data model to a relational database
3.1 Introduction
Once a data model is developed, the next task is to convert the data model to a relational data-
base. he goal of this chapter is to prepare for and carry out the conversion of a data model to a
relational database. A relational database is constructed with tables and relationships among these
tables. Your irst task is to study table structures. Concepts such as relations, keys, and functional
dependency will be studied in this chapter. hen, you will learn how to normalize the table struc-
tures to avoid database operation problems. Next, you will modify your data model according to
the desired table structures. Lastly, the modiied data model will be ready to be converted to a
relational database.
3.2 Overview of Relational Database
In the 1970s, Edgar Codd introduced the relational database concept. In his proposal, the data
model components, entity, attribute, and entity instance have the corresponding names relation,
attribute, and tuple, respectively. he words relation, attribute, and tuple are from a mathematical
set theory from which Edgar Codd developed the relational database. For business application,
less rigorous names are used for entity, attribute, and entity instance. In a relational database,
