Deductive Databases with Conditional Facts
نویسنده
چکیده
Department of Computer Science The Wichita State University Wichita, Kansas 67260-0083, USA e-mail: [email protected] Abstract. We introduce the notion of conditional facts in deductive databases. The language used to express the conditions in the basic facts does not involve constructs used to describe the database and is motivated by its potential usefulness in expressing disjunctive facts and answering queries in disjunctive deductive databases. We present a bottom-up procedure that uses tabular structures to represent the conditional facts and computes the intended meaning of conditional deductive databases. We show how this procedure can be used to answer queries in a subclass of disjunctive deductive databases which involves disjunctive facts but only definite rules.
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