Encyclopedia of Database Systems

2018 Edition
| Editors: Ling Liu, M. Tamer Özsu

Normal Forms and Normalization

  • Marcelo ArenasEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-8265-9_1237


A normal form defines a condition over a set of data dependencies, or semantic constraints, that has been specified as part of a database schema. This condition is used to check whether the design of the database has some desirable properties (for example, the database does not store redundant information), and if this is not the case, then it can also be used to convert the poorly designed database into an equivalent well-designed one.

Historical Background

Information is one of the most - if not the most - valuable assets of a company. Therefore, organizations need tools to allow them to structure, query and analyze their data, and, in particular, they need tools providing simple and fast access to their information.

During the last 40 years, relational databases have become the most popular computer application for storing and analyzing information. The simplicity and elegance of the relational model, where information is stored just as tables, has largely contributed to...

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Recommended Reading

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Pontifical Catholic University of ChileSantiagoChile

Section editors and affiliations

  • Leonid Libkin
    • 1
  1. 1.School of InformaticsUniversity of EdinburghEdinburghUK