Answering atomic queries in indefinite deductive databases

Answering queries in indefinite systems is a difficult problem both computationally, since it involves non‐Horn clauses and factoring, and conceptually, concerning producing beliefs for formulas not derivable from the system. to provide a basis for reasonable beliefs, we propose new criteria as an alternative to the Full Information Principle. Then an approach to producing stable beliefs, called Plausible World Assumption (PWA), is introduced. It is shown how a set of non‐Horn clauses can be transformed into a set of so called singleton‐head‐rules such that evaluation of a given query is reduced to processing of a set of Horn clauses relevant to the query. Finally, algorithms are presented for computing facts and beliefs for atomic queries in accord with the PWA. This method is shown to be more efficient than the known techniques for query evaluation in indefinite systems.

[1]  Carlo Zaniolo,et al.  On the implementation of a simple class of logic queries for databases , 1985, PODS.

[2]  Eliezer L. Lozinskii,et al.  A problem-oriented inferential database system , 1986, TODS.

[3]  Allen Van Gelder,et al.  A message passing framework for logical query evaluation , 1986, SIGMOD '86.

[4]  Dov M. Gabbay,et al.  Theoretical Foundations for Non-Monotonic Reasoning in Expert Systems , 1989, Logics and Models of Concurrent Systems.

[5]  Raymond Reiter,et al.  Deductive Question-Answering on Relational Data Bases , 1977, Logic and Data Bases.

[6]  Allen Van Gelder,et al.  Negation as Failure using Tight Derivations for General Logic Programs , 1988, J. Log. Program..

[7]  David Maier,et al.  Magic sets and other strange ways to implement logic programs (extended abstract) , 1985, PODS '86.

[8]  Laurent Vieille,et al.  Recursive Axioms in Deductive Databases: The Query/Subquery Approach , 1986, Expert Database Conf..

[9]  Jack Minker,et al.  Logic and Databases: A Deductive Approach , 1984, CSUR.

[10]  Jack Minker,et al.  On recursive axioms in deductive databases , 1983, Inf. Syst..

[11]  Randy Goebel,et al.  Gracefully adding negation and disjunction to Prolog , 1986, ICLP.

[12]  Georges Gardarin,et al.  Evaluation of database recursive logic programs as recurrent function series , 1986, SIGMOD '86.

[13]  Keith L. Clark,et al.  Negation as Failure , 1987, Logic and Data Bases.

[14]  Richard C. T. Lee,et al.  Symbolic logic and mechanical theorem proving , 1973, Computer science classics.

[15]  R. Reiter.  On Closed World Data Bases , 1987, Logic and Data Bases.

[16]  Adrian Walker,et al.  Towards a Theory of Declarative Knowledge , 1988, Foundations of Deductive Databases and Logic Programming..

[17]  J. Ullman,et al.  Complexity of a top-down capture rule , 1984 .

[18]  Teodor C. Przymusinski.  Query Answering in Circumscriptive and Closed-World Theories , 1986, AAAI.

[19]  Vladimir Lifschitz,et al.  Computing Circumscription , 1985, IJCAI.

[20]  Michael Kifer,et al.  Filtering Data Flow in Deductive Databases , 1986, ICDT.

[21]  Raymond Reiter,et al.  A Logic for Default Reasoning , 1987, Artif. Intell..

[22]  John McCarthy,et al.  Circumscription - A Form of Non-Monotonic Reasoning , 1980, Artif. Intell..

[23]  John McCarthy,et al.  Applications of Circumscription to Formalizing Common Sense Knowledge , 1987, NMR.

[24]  Donald W. Loveland,et al.  Automated theorem proving: a logical basis , 1978, Fundamental studies in computer science.

[25]  Richard Hull,et al.  Positivism vs minimalism in deductive databases , 1985, PODS '86.

[26]  Lawrence J. Henschen,et al.  On compiling queries in recursive first-order databases , 1984, JACM.

[27]  Catriel Beeri,et al.  On the power of magic , 1987, J. Log. Program..

[28]  Stuart C. Shapiro,et al.  Using Active Connection Graphs for Reasoning with Recursive Rules , 1981, IJCAI.

[29]  Jeffrey D. Ullman,et al.  Implementation of logical query languages for databases , 1985, TODS.

[30]  Jack Minker,et al.  On Indefinite Databases and the Closed World Assumption , 1987, CADE.

[31]  Pierre Siegel,et al.  Saturation, Nonmonotonic Reasoning and the Closed-World Assumption , 1985, Artif. Intell..

[32]  Eliezer L. Lozinskii,et al.  Evaluating Queries in Deductive Databases by Generating , 1985, IJCAI.