Answering queries addressed to the rule base of a deductive database
The purpose of this study is the answer generation when querying a rule base in the context of deductive databases. We suppose the rule base to be a non recursive set of rules, represented by closed range restricted formulae. The query is an open range restricted formula, in which bound variables are existentially quantified. The answer to a query is a formula (and not a set of tuples). We use the formalism of the first-order predicate calculus without equality, restricted to Horn clauses. The generation method is based on a complete and sound strategy : we construct a linear input resolution tree by a depth-first method. The corresponding algorithm terminates under our hypothesis.
KeywordsRule Base Horn Clause Deductive Database Atomic Fact Negative Literal
Unable to display preview. Download preview PDF.
- [CHOL1]L. Cholvy, R. Demolombe "Querying a rule base", First international conference on expert database systems, Charleston, USA, April 1987.Google Scholar
- [CHOL2]L. Cholvy "Programme de recherche coordonnées de troisième génération" ONERA-CERT internal report, no2/3274/DERI, February 1987.Google Scholar
- [CHOL3]L. Cholvy "Intensional answers", ONERA/CERT internal reportGoogle Scholar
- [CHAN]C.L. Chang, R.C.T. Lee "Computer science and applied mathematics", Academic Press, 1973.Google Scholar
- [DML1]R. Demolombe "Syntactical characterization of a subset of domain independent formulas" ONERA-CERT internal report, 1982.Google Scholar
- [DML2]R. Demolombe ONERA/CERT internal report, 1987.Google Scholar
- [GALL]H. Gallaire, J. Minker, J.M. Nicolas "Logic and database: a deductive approach", ACM Surveys, vol. 16, no2, 153–165, June 1984.Google Scholar
- [MORG]C. G. Morgan "Automated hypothesis generation using extended inductive resolution" Proc. of IJCAI, 351–356, 1975.Google Scholar
- [PASC]E. Pascual "Interrogation d'une base de règles dans le cadre de bases de données déductives", DEA report, ENSAE Toulouse, June 1987.Google Scholar