BIT Numerical Mathematics

, Volume 27, Issue 2, pp 157–162 | Cite as

On finding a worst-case optimal Fourth Normal Form database decomposition

  • G. Loizou
  • P. Thanisch
Part I Computer Science
Received:
Revised:

Abstract

Although several Fourth Normal Form (4NF) decomposition algorithms have been published, the problem's computational complexity remains an open question. Part of the difficulty is that no one has established an upper bound on the size of a 4NF decomposition scheme for a given number of attributes. We prove such an upper bound and we present an algorithm which is worst-case optimal: it never produces a 4NF decomposition scheme that is larger than the upper bound.

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F.2 H.2.1 
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Copyright information

© BIT Foundations 1987

Authors and Affiliations

  • G. Loizou
    • 1
    • 2
  • P. Thanisch
    • 1
    • 2
  1. 1.Department of Computer Science, Birkbeck CollegeUniversity of LondonLondonEngland
  2. 2.Department of Computer ScienceHeriot-Watt UniversityEdinburghScotland

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