Một vài kết quả về các ràng buộc trên các giá trị không trong CSDL quan hệ
Author affiliations
DOI:
https://doi.org/10.15625/1813-9663/5/3/11176Abstract
In [2] B.S. Goldstein introduced the concept of “disjunctive existence constraint” together with a sound and complete set of inference rules (4 rules), as a means for using null values.
In this paper, we investigate cases in which the system of three inference rules is complete.
Finally, an algorithm for computing the closure X* of X is also given.
Metrics
Metrics Loading ...
Downloads
Published
01-02-2018
How to Cite
[1]
T. D. Tuan, “Một vài kết quả về các ràng buộc trên các giá trị không trong CSDL quan hệ”, JCC, vol. 5, no. 3, p. 16–23, Feb. 2018.
Issue
Section
Computer Science
License
1. We hereby assign copyright of our article (the Work) in all forms of media, whether now known or hereafter developed, to the Journal of Computer Science and Cybernetics. We understand that the Journal of Computer Science and Cybernetics will act on my/our behalf to publish, reproduce, distribute and transmit the Work.2. This assignment of copyright to the Journal of Computer Science and Cybernetics is done so on the understanding that permission from the Journal of Computer Science and Cybernetics is not required for me/us to reproduce, republish or distribute copies of the Work in whole or in part. We will ensure that all such copies carry a notice of copyright ownership and reference to the original journal publication.
3. We warrant that the Work is our results and has not been published before in its current or a substantially similar form and is not under consideration for another publication, does not contain any unlawful statements and does not infringe any existing copyright.
4. We also warrant that We have obtained the necessary permission from the copyright holder/s to reproduce in the article any materials including tables, diagrams or photographs not owned by me/us.
