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The Nested Universal Relation Database Model [[electronic resource] /] / by Mark Levene



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Autore: Levene Mark Visualizza persona
Titolo: The Nested Universal Relation Database Model [[electronic resource] /] / by Mark Levene Visualizza cluster
Pubblicazione: Berlin, Heidelberg : , : Springer Berlin Heidelberg : , : Imprint : Springer, , 1992
Edizione: 1st ed. 1992.
Descrizione fisica: 1 online resource (X, 182 p.)
Disciplina: 005.75/6
Soggetto topico: Data structures (Computer science)
Database management
Computers
Software engineering
Data Structures and Information Theory
Database Management
Computation by Abstract Devices
Software Engineering
Note generali: Bibliographic Level Mode of Issuance: Monograph
Nota di contenuto: The underlying database models -- The null extended nested relational model -- Null extended data dependencies and the extended chase -- A universal relation model for a nested database -- A universal relation model for a single nested relation -- Concluding remarks and ongoing research.
Sommario/riassunto: This monograph describes a method of data modelling whose basic aim is to make databases easier to use by providing them with logical data independence. To achieve this, the nested UR (universal relation) model is defined by extending the classical UR model to nested relations. Nested relations generalize flat relations and allow hierarchically structured objects to be modelled directly, whereas the classical UR model allows the user to view the database as if it were composed of a single flat relation. The author presents a comprehensive formalisation of the nested relational model, which incorporated null values into the model. Functional data dependencies and the classical notion of lossless decomposition are extended to nested relations and an extended chase procedure is defined to test the satisfaction of the data dependencies. The nested UR model is defined, and the classical UR model is shown to be a special case of the nested model.This implies that an UR interface canbe implemented by using the nested UR model, thus gaining the full advantages of nested relations over flat relations.
Titolo autorizzato: Nested universal relation database model  Visualizza cluster
ISBN: 3-540-47110-3
Formato: Materiale a stampa
Livello bibliografico Monografia
Lingua di pubblicazione: Inglese
Record Nr.: 996465734003316
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Serie: Lecture Notes in Computer Science, . 0302-9743 ; ; 595