Influence of granularity level in fuzzy functional dependencies

  • J. C. Cubero
  • J. M. Medina
  • M. A. Vila
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 747)


Relational Databases (R.D) can be considered the most widely used approach to Databases [5]. But in Classical R.D it is not possible to store or treat vague information.

When extending R.D to Fuzzy Relational Databases (F.R.D) it is needed more than a system capable of storing and treating fuzzy information in tables or relations: it must extend the notion that a relation represents the association between a set of key attributes and other set of attributes relationed with the former. The concept of functional dependency (f.d) is the key to understand and treat this problem.

In this paper we will present a refinement of the definition of f.f.d given in [6] attending to granularity levels imposed in the attributes. We justify this imposition from a semantic point of view.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • J. C. Cubero
    • 1
  • J. M. Medina
    • 1
  • M. A. Vila
    • 1
  1. 1.Dpto. Ciencias de la Computación e Inteligencia Artificial Facultad de CienciasUniversidad de GranadaGranadaSpain

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