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The Relational Model

  • S. M. Deen
Part of the Macmillan Computer Science Series book series

Abstract

A relation is a mathematical term for a two-dimensional table such as the one shown in figure 3.15. It is characterised by rows and columns, each entry there being a data item value. The reason for calling this a relation rather than a matrix lies in the lack of homogeneity in its entries — the entries are homogeneous in the columns but not in the rows. A relational data base consists of such relations, which can be stored on a physical device in a variety of ways.

Keywords

Quantity Order Unit Price Relational Algebra Common Domain Access Path 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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    D. L. Childs, Proc. IFIP Congress 1968 (North Holland) p. 162.Google Scholar
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    For brief descriptions of these systems, see C. J.Date, An Introduction To Data Base Systems (Addison-Wesley, New York, 1975) chapter 8.Google Scholar
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    C. W. Bachman, quoted in Computer Weekly, April 8, 1976.Google Scholar

Copyright information

© S. M. Deen 1977

Authors and Affiliations

  • S. M. Deen
    • 1
  1. 1.Department of Computing ScienceUniversity of AberdeenUK

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