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Journal of Information Science and Engineering, Vol. 20 No. 5, pp. 981-999 (September 2004)

The Exclusive-or Disjunctive Information in
Relational Databases

Chien-Chou Shih, Ding-An Chiang* and Wen-Hsing Kao*
Department of Information and Communication
*Department of Information Engineering
Tamkang University
Tamsui, 251 Taiwan

In this paper, we propose an extended relational model to accommodate exclusive-or disjunctive information. The proposed model is defined by first-order logic. The answers to a query contain both sure answers and maybe answers. To guarantee that the manipulation power of the proposed model is as good as that of the classical relational model, we prove that the classical properties of the database, uniquely determined and well-defined relational algebra, are preserved in our proposed model.

Keywords: disjunctive information, incomplete information, well-defined relational algebra, relational database, uniquely determined

Full Text () Retrieve PDF document (200409_10.pdf)

Received May 27, 2002; revised January 23, 2003; accepted March 31, 2003.
Communicated by Ming-Syan Chen.