Generalized dependencies in relational databases

id. Sali Attila and Sali Attila: Generalized dependencies in relational databases. In: Acta cybernetica, (13) 4. pp. 431-438. (1998)

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A new type of dependencies in a relational database model introduced in [5] is investigated. If b is an attribute, A is a set of attributes then it is said that b (p, g, )-depends on A, in notation A ^^ b, in a database relation r if there are no q + 1 tuples in r such that they have at most p different values in each column of A, but 9 + 1 different values in 6. (1, l)-dependency is the classical functional dependency. Let ¿7{A) denote the set {b: A 6}. The set function J\ 2n —> 2 n becomes a closure if p = q. Results on representability of closures by (p, p)-dependencies are presented.

Item Type: Article
Journal or Publication Title: Acta cybernetica
Date: 1998
Volume: 13
Number: 4
ISSN: 0324-721X
Page Range: pp. 431-438
Language: English
Place of Publication: Szeged
Related URLs:
Uncontrolled Keywords: Számítástechnika, Kibernetika
Additional Information: Bibliogr.: 438. p. ; összefoglalás angol nyelven
Subjects: 01. Natural sciences
01. Natural sciences > 01.02. Computer and information sciences
Date Deposited: 2016. Oct. 15. 12:26
Last Modified: 2022. Jun. 13. 15:52

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