id. Sali Attila and Sali Attila: Generalized dependencies in relational databases. In: Acta cybernetica, (13) 4. pp. 431-438. (1998)
Preview |
Cikk, tanulmány, mű
cybernetica_013_numb_004_431-438.pdf Download (601kB) | Preview |
Abstract
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: | http://acta.bibl.u-szeged.hu/38506/ |
| 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 |
| URI: | http://acta.bibl.u-szeged.hu/id/eprint/12602 |
Actions (login required)
 |
View Item |
