Nonstandard database
interaction from metalogic programming
Troels Andreasen, Henning Christiansen
Department of Computer Science
Roskilde University, P.O.Box 260, DK-4000 Roskilde, Denmark
In order to meet the demands for
more expressive and
flexible ways to interact with
a database,
it is often relevant to go beyond what can be formalized
in an obvious way in first order logic
or its traditional,
higher-order or modal extensions.
Metalogical programming is proposed as a framework
in which new query-answering and update
mechanisms can be characterized and implemented.
A model is shown, extending deductive databases
by a classification of the clauses in the database,
an integration of nonstandard inference rules, and
a notion of proof constraints.
In this model, we can embed flexibility
by transformations of
query and subgoals, e.g., using taxonomy rules
in the opposite direction for widening an
otherwise failed subgoal.
In the same model, a variation of counterfactual reasoning can
be characterized;
it can be implemented efficiently
and useful database applications can be shown.
Dynamic aspect of databases such as view update and datamining
can be seen as cases of
abductive and inductive reasoning,
which can be characterized in
straight-forward ways in terms of metalogical
statements involving a reversible metainterpreter.
Andreasen, T., Christiansen, H., Legind Larsen, H. (eds.)
Flexible Query Answering Systems,
Kluwer Academic Publishers, 1997. pp. 61-78.
Edited collection of papers,
see
Preface,
List of contents.