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@inproceedings{DBLP:conf/vldb/OlaO89,
author = {Adegbemiga Ola and
Gultekin {\"O}zsoyoglu},
editor = {Peter M. G. Apers and
Gio Wiederhold},
title = {A Family of Incomplete Relational Database Models},
booktitle = {Proceedings of the Fifteenth International Conference on Very
Large Data Bases, August 22-25, 1989, Amsterdam, The Netherlands},
publisher = {Morgan Kaufmann},
year = {1989},
isbn = {1-55860-101-5},
pages = {23-31},
ee = {db/conf/vldb/OlaO89.html},
crossref = {DBLP:conf/vldb/89},
bibsource = {DBLP, http://dblp.uni-trier.de}
}
In this paper, we utilize intervals for unknown values in incomplete relationaldatabases. We use tables to represent unknown relations. First, we define three partial tuple types in a table to specify incompletenessrelationships among tuples of the same table. For tuples of different tables, we distinguish between the cases where incompleteness are introduced at the relation level, tuple level or attribute-value level. And, based on these relationships among tuples in different tables, we present a family of incomplete relational database models.
For each of the models, the query evaluation is sound (i.e., no incorrect results are derivable). None of the models is complete (i.e., all valid conclusions are derivable). We briefly compare two of the models in the family with other approaches.
Considering each table tuple as a set of d-dimensional cubes, each model in thefamily of models presented in this paper can be considered as a geometric database model. We are presently implementing a version of one of the models. We briefly summarize the geometric operations and the primitive update semantics being utilized in the implementation.
Copyright © 1989 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.
