A server for Fuzzy SQL queries

  • José Galindo
  • Juan M. Medina
  • Olga Pons
  • Juan C. Cubero
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1495)


The client-server model is being used mostly in the actual DataBase Management Systems (DBMS). However, these DBMS do not allow either to make flexible queries to the database or to store vague information in it. We have developed a FSQL Server for a Fuzzy Relational Database (FRDB). The FSQL language (Fuzzy SQL) is an extension of the SQL language that allows us to write flexible conditions in our queries. This Server has been developed for Oracle, following the model GEFRED, a theoric model for FRDB that includes fuzzy attributes to store vague information in the tables. The FSQL Server allows us to make flexible queries about traditional (crisp) or fuzzy attributes and we can use linguistic labels defined on any attribute.


Information Storage and Retrieval Flexible and Fuzzy Queries Fuzzy Relational Databases Fuzzy SQL 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • José Galindo
    • 1
  • Juan M. Medina
    • 2
  • Olga Pons
    • 2
  • Juan C. Cubero
    • 2
  1. 1.Dpto. Lenguajes y Ciencias de la ComputaciónUniversidad de MálagaMálagaSpain
  2. 2.Dpto. Ciencias de la Computación e I.A.Universidad de GranadaGranadaSpain

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