SQLf Query Functionality on Top of a Regular Relational Database Management System

  • Patrick Bosc
  • Olivier Pivert
Part of the Studies in Fuzziness and Soft Computing book series (STUDFUZZ, volume 39)


This paper is mainly concerned with the extension of database management systems querying capabilities, so that users may address queries involving preferences and get discriminated answers. The use of flexible (gradual) predicates interpreted in the framework of the fuzzy set theory is advocated for defining a query language, called SQLf. This language enlarges the functionalities offered by SQL and it is considered here from a query processing point of view.


Database Query Language Fuzzy Queries SQLf Query Evaluation 


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  1. [1]
    Bosc P. (1996) Some approaches for processing SQLf nested queries. Int. J. Intell. Syst. (11), 613–632.Google Scholar
  2. [2]
    Bosc P., Pivert O. (1992) Some approaches for relational databases flexible querying. J. Intell. Inf. Syst. (1), 323–354.Google Scholar
  3. [3]
    Bosc P., Pivert O. (1993) On the evaluation of simple fuzzy relational queries: principles and measures. In: Lowen R., Roubens M. (eds) Fuzzy logic–State of the Art. Kluwer Academic Publishers, 355–364.CrossRefGoogle Scholar
  4. [4]
    Bosc P., Pivert O. (1995) On the efficiency of the alpha-cut distribution method to evaluate simple fuzzy relational queries. In: Bouchon-Meunier B., Yager R.R., Zadeh L.A. (eds) Advances in Fuzzy Systems–Applications and Theory vol. 4, Fuzzy Logic and Soft Computing. World Scientific, 251–260.Google Scholar
  5. [5]
    Bosc P., Pivert O. (1995) SQLf: a relational database language for fuzzy querying. IEEE Trans. Fuzzy Syst. (3), 1–17.Google Scholar
  6. [6]
    Bosc P., Liétard L., Pivert O. (1995) Quantified statements in a flexible relational query language. In: Proc. ACM Symp. Applied Computing (SAC’95), Nashville (USA), 488–492.Google Scholar
  7. [7]
    Bosc P., Liétard L., Pivert O. (1995) Quantified statements and database fuzzy querying. In: Bosc P., Kacprzyk J. (eds) Fuzziness in Database Management Systems. Physica Verlag, 275–308.Google Scholar
  8. [8]
    Bosc P., Dubois D., Pivert O., Prade H. (1997) Flexible queries in relational databases–The example of the division operator. Theoretical Comp. Sc. (171), 281–302.Google Scholar
  9. [9]
    Ichikawa T., Hirakawa M. (1986) ARES: a relational database with the capability of performing flexible interpretation of queries. IEEE Trans. Soft. Eng. (12), 624–634.Google Scholar
  10. [10]
    Kacprzyk J., Ziolkowski A. (1995) FQUERY for ACCESS: fuzzy querying for a Windows-based DBMS. In: Bosc P., Kacprzyk J. (eds) Fuzziness in Databases Management Systems. Physica Verlag, 415–433.Google Scholar
  11. [11]
    Lacroix M., Lavency P. (1987) Preferences: putting more knowledge into queries. In: Proc. 13th VLDB Conf., Brighton (GB), 217–225.Google Scholar
  12. [12]
    Medina J.M., Vila M.A., Cubero J.C., Pons O. (1995) Towards the Implementation of a Generalized Fuzzy Relational Model. Fuzzy Sets and Syst. (75), 273–289.Google Scholar
  13. [13]
    Motro A. (1988) VAGUE: a user interface to relational databases that permits vague queries. ACM Trans. Off. Inf. Syst. (6), 187–214.Google Scholar
  14. [14]
    Prade H., Testemale C. (1984) Generalizing database relational algebra for a treatment of incomplete or uncertain information and vague queries. Inf. Sc. (34), 115–143.Google Scholar
  15. [15]
    Tahani V. (1977) A conceptual framework for fuzzy query processing; a step toward very intelligent database systems. Inf. Processing and Management (13), 289–303.Google Scholar
  16. [16]
    Umano M. (1982) FREEDOM-O: a fuzzy database system. In: Gupta M.M., Sanchez E. (eds) Fuzzy Information and Decision Processes. North-Holland, 339–347.Google Scholar
  17. [17]
    Zemankova M., Kandel A. (1984) Fuzzy Relational Databases - A Key to Expert Systems. Verlag TUV Rheinland, Köln.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Patrick Bosc
    • 1
  • Olivier Pivert
    • 1
  1. 1.Technopole AnticipaIRISA/ENSSATLannion CedexFrance

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