# A simple guide to five normal forms in relational database theory

@article{Kent1983ASG, title={A simple guide to five normal forms in relational database theory}, author={William Kent}, journal={Commun. ACM}, year={1983}, volume={26}, pages={120-125} }

<italic>The concepts behind the five principal normal forms in relational database theory are presented in simple terms.</italic>

## 282 Citations

### Performance Criteria for Relational Database Normalization

- Computer Science
- 1989

the efficiency of We find that in almost all cases where there are multi-valued dependencies, the normal form is more efficient.

### A theory of data dependencies over relational expressions

- Computer ScienceInternational Journal of Computer & Information Sciences
- 2004

A class of integrity constraints for the relational model of data, called implicational dependencies over relational expressions (or, simply, IDEXs), is defined and a refutation procedure, which is a direct adaptation of first-order analytic tableaux, is introduced.

### Representation of Data Structures Using the Entity Relationship Model and the Transformation in Relational Databases

- Computer Science
- 1996

It is shown here how the structure of relationships, as well as the properties of Relationships, and the role of language in this discussion can be changed over time from simple to complex.

### Normalization of relations and PROLOG

- Computer ScienceCACM
- 1986

The program presented here implements several normalization algorithms and is suitable for the interactive design of small database applications and as a teaching aid.

### Tutorial: The relational data model for Design Automation

- Computer ScienceDAC
- 1983

This tutorial explains what the relational data model is and how database management systems based on it can be used with Design Automation applications.

### A simple taxonomy for distributed mutual exclusion algorithms

- Computer ScienceOPSR
- 1991

This short paper examines the two basic principles from which distributed mutual exclusion algorithms are designed : permission-based and token-based principles. This presentation is done in a…

### Re-Engineering Relational Normal Forms in an Object-Oriented Framework

- Computer ScienceOOIS
- 1997

This paper reviews relational normal forms, interprets them in an object-oriented context, and provides guidelines to port relationalnormal forms to an object the database designer must reconcile normalization processes with newer approaches that identify the core application classes.

### The practical need for fourth normal form

- MedicineSIGCSE '92
- 1992

The need to understand and user fourth normal form is more important than previously believed after a study of forty organizational databases found that nine of them contained data violating fourthnormal form.

### MULTIVALUED DEPENDENCIES AND FIFTH NORMAL FORM OF RELATIONAL DATABASES

- Computer Science
- 2014

This work tries to represent, how the concept of multivalued dependency is used in Fifth Normal Form (5NF), a Forth Normal Form for relational schemata.

## References

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We discuss the relationship between normal forms in a relational database and an allowed set of relational operators. We define "projection-join normal form" (PJ/NF), which is the ultimate normal…

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An improved third normal form is defined and an algorithm is given to construct a set of relations from a given set of functional dependencies in such a way that the superfluous attributes are guaranteed to be removed.

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This paper illustrates the removal of repeating groups, hierarchic and plex structures, and cross-referencing structures and the simplification of data base relations by normalization is discussed.

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A model based on n-ary relations, a normal form for data base relations, and the concept of a universal data sublanguage are introduced and certain operations on relations are discussed and applied to the problems of redundancy and consistency in the user's model.

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A model based on n-ary relations, a normal form for data base relations, and the concept of a universal data sublanguage are introduced and certain operations on relations are discussed and applied to the problems of redundancy and consistency in the user's model.

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### CR Categories and Subjects: H.2.1 [Database Management]: Logical Design--normal forms General Term

- CR Categories and Subjects: H.2.1 [Database Management]: Logical Design--normal forms General Term