Identification, genericity and consistency in object-oriented databases

  • Klaus-Dieter Schewe
  • Joachim W. Schmidt
  • Ingrid Wetzel
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 646)


It is claimed that object-oriented databases overcome many of the limitations of the relational data model especially by generalizing the notion of object identification. A clear distinction between objects and values turns out to be essential for the object-oriented approach whereas the relational model is based exclusively on values. Since, however, value uniqueness within scopes is a quite natural constraint for a wide class of applications, identification by value is also of interest for object-oriented datamodels.

Hence, in this paper we concentrate on those classes where the extents are completely representable by values. We formalize some basic concepts of object-oriented databases and show that the finiteness of a database and the existence of finitely representable recursive types are sufficient to decide value-representability.

Another advantage of the relational approach is the existence of structurally determined canonical update operations. We show that this property can be carried over to object-oriented datamodels iff classes are value-representable. Moreover, in this case database consistency with respect to implicitly specified referential and inclusion constraints will be automatically preserved.


Representation Type Uniqueness Constraint Identification Graph Object Identifier Explicit Constraint 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    S. Abiteboul: Towards a deductive object-oriented database language, Data & Knowledge Engineering, vol. 5, 1990, pp. 263–287Google Scholar
  2. 2.
    S. Abiteboul, P. Kanellakis: Object Identity as a Query Language Primitive, in Proc. SIGMOD, Portland Oregon, 1989, pp. 159–173Google Scholar
  3. 3.
    A. Albano, G. Ghelli, R. Orsini: A Relationship Mechanism for a Strongly Typed Object-Oriented Database Programming Language, in A. Sernadas (Ed.): Proc. VLDB 91, Barcelona 1991Google Scholar
  4. 4.
    M. Atkinson, F. Bancilhon, D. DeWitt, K. Dittrich, S. Zdonik: The Object-Oriented Database System Manifesto, Proc. 1st DOOD, Kyoto 1989Google Scholar
  5. 5.
    F. Bancilhon, G. Barbedette, V. Benzaken, C. Delobel, S. Gamerman, C. Lécluse, P. Pfeffer, P. Richard, F. Velez: The Design and Implementation of O 2 an Object Oriented Database System, Proc. of the ooDBS II workshop, Bad Münster, FRG, September 1988Google Scholar
  6. 6.
    C. Beeri: Formal Models for Object-Oriented Databases, Proc. 1st DOOD 1989, pp. 370–395Google Scholar
  7. 7.
    C. Beeri: A formal approach to object-oriented databases, Data and Knowledge Engineering, vol. 5 (4), 1990, pp. 353–382Google Scholar
  8. 8.
    C. Beeri, Y. Kornatzky: Algebraic Optimization of Object-Oriented Query Languages, in S. Abiteboul, P. C. Kanellakis (Eds.): Proceedings of ICDT 90, Springer LNCS 470, pp. 72–88Google Scholar
  9. 9.
    M. Carey, D. DeWitt, S. Vandenberg: A Data Model and Query Language for EXO-DUS, Proc. ACM SIGMOD 88Google Scholar
  10. 10.
    M. Caruso, E. Sciore: The VISION Object-Oriented Database Management System, Proc. of the Workshop on Database Programming Languages, Roscoff, France, September 1987Google Scholar
  11. 11.
    D. Fishman, D. Beech, H. Gate, E. Chow et al.: IRIS: An Object-Oriented Database Management System, ACM ToIS, vol. 5(1), January 1987Google Scholar
  12. 12.
    S. Khoshafian, G. Copeland: Object Identity, Proc. 1st Int. Conf. on OOPSLA, Portland, Oregon, 1986Google Scholar
  13. 13.
    W. Kim, N. Ballou, J. Banerjee, H. T. Chou, J. Garza, D. Woelk: Integrating an Object-Oriented Programming System with a Database System, in Proc. OOPSLA 1988Google Scholar
  14. 14.
    D. Maier, J. Stein, A. Ottis, A. Purdy: Development of an Object-Oriented DBMS, OOPSLA, September 1986Google Scholar
  15. 15.
    K.-D. Schewe, B. Thalheim, I. Wetzel, J. W. Schmidt: Extensible Safe Object-Oriented Design of Database Applications, University of Rostock, Technical report, September 1991Google Scholar
  16. 16.
    K.-D. Schewe, I. Wetzel, J. W. Schmidt: Towards a Structured Specification Language for Database Applications, in Proc. Int. Workshop on the Specification of Database Systems, Glasgow, Springer WICS 1991Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • Klaus-Dieter Schewe
    • 1
  • Joachim W. Schmidt
    • 1
  • Ingrid Wetzel
    • 1
  1. 1.Dept. of Computer ScienceUniversity of HamburgHamburg 54

Personalised recommendations