A logic programming framework for modelling temporal objects
Author
Kesim, N.
Sergot, M.
Date
1996-10Source Title
IEEE Transactions on Knowledge and Data Engineering
Print ISSN
1041-4347
Electronic ISSN
1558-2191
Publisher
IEEE
Volume
8
Issue
5
Pages
724 - 741
Language
English
Type
ArticleItem Usage Stats
114
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77
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Abstract
We present a general approach for modeling temporal aspects of objects in a logic programming framework. Change is
formulated in the context of a database which stores explicitly a record of all changes that have occurred to objects and thus
(implicitly) all states of objects in the database. A snapshot of the database at any given time is an object-oriented database, in the
sense that it supports an object-based data model. An object is viewed as a collection of simple atomic formulas, with support for an
explicit notion of object identity, classes and inheritance. The event calculus is a treatment of time and change in first-order classical
logic augmented with negation as failure. The paper develops a variant of the event calculus for representing changes to objects,
including change in internal state of objects, creation and deletion of objects, and mutation of objects over time. The concluding sections
present two natural and straightforward extensions, to deal with versioning of objects and schema evolution, and a sketch of
implementation strategies for practical application to temporal object-oriented databases.
Keywords
Object-oriented DatabasesObject Versioning
Deductive Databases
Temporal Databases
Temporal Reasoning
Event Calculus
Logic Programming