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@inproceedings{DBLP:conf/vldb/Cuppens96,
author = {Fr{\'e}d{\'e}ric Cuppens},
editor = {T. M. Vijayaraman and
Alejandro P. Buchmann and
C. Mohan and
Nandlal L. Sarda},
title = {Querying a Multilevel Database: A Logical Analysis},
booktitle = {VLDB'96, Proceedings of 22th International Conference on Very
Large Data Bases, September 3-6, 1996, Mumbai (Bombay), India},
publisher = {Morgan Kaufmann},
year = {1996},
isbn = {1-55860-382-4},
pages = {484-494},
ee = {db/conf/vldb/Cuppens96.html},
crossref = {DBLP:conf/vldb/96},
bibsource = {DBLP, http://dblp.uni-trier.de}
}
This paper proposes a new formal model and semantics for answering queries in a multilevel polyinstantiated database. A polyinstantiated database may contain some contradictory facts distinguished by their classification. The main objective of this paper is then to provide the user cleared at a given level with a consistent and complete view of the multilevel database corresponding to his clearance level.
In our model, a multilevel database is simply viewed as a set of ordinary single-level databases. This model is based on propositional logic and each single-level database is associated with its logical models, as in the model- theoretic approach. It includes the possibility to hide some parts of the database schema. Finally, it may be used as a formal semantics for multiple deductive databases.
Copyright © 1996 by the VLDB Endowment. Permission to copy without fee all or part of this material is granted provided that the copies are not made or distributed for direct commercial advantage, the VLDB copyright notice and the title of the publication and its date appear, and notice is given that copying is by the permission of the Very Large Data Base Endowment. To copy otherwise, or to republish, requires a fee and/or special permission from the Endowment.
