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ERwin Methods Guide |
6 |
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Normalization
Introduction
Normalization is the process of making a database design comply with the design rules outlined by E. F. Codd for relational databases. Following the rules for normalization, you can control and eliminate data redundancy by removing all model structures that provide multiple ways to know the same fact.
The goal of normalization is to ensure that there is only one way to know a “fact.” A useful slogan summarizing this goal is:
ONE FACT IN ONE PLACE! |
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To provide a basic understanding of the principles of normalization, this |
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chapter includes a variety of examples of common design problems and |
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normalization solutions. |
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Chapter Contents |
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Overview of the Normal Forms .......................................................................... |
72 |
Common Design Problems .................................................................................. |
73 |
Unification............................................................................................................. |
84 |
How Much Normalization Is Enough?............................................................... |
86 |
ERwin Support for Normalization...................................................................... |
88 |
Normalization ∙ 71