From Wikipedia, the free encyclopedia
Database theory
The universal relation assumption in relational databases states that one can place all data attributes into a (possibly very wide) table, which may then be decomposed into smaller tables as needed.[1]
However, the assumption that a single large table can capture real database designs is often plagued with a number of difficulties.[2] The "nested universal relation" model has attempted to address some of the problems and offer improvements.[3]
References
[edit]- ^ I. T. Hawryszkiewycz, Database analysis and design, 1984. ISBN 0-574-21485-2, pages 59–62.
- ^ Carlo Zaniolo, Advances in database technology--EDBT 2000, 2000. ISBN 3-540-67227-3, page 276
- ^ Mark Levene, The nested universal relation database model, 2000. ISBN 3-540-55493-9, pages 1–5.
External links
[edit]- Who won the Universal Relation wars? by Alberto Mendelzon
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