Substitution-based compilation of extended rules in deductive databases
Query compilation in a deductive database refers to the process of continually replacing defined literals in rule bodies by their definitions until rules with references only to stored relations are obtained. The compiled forms generate the same tuples for the head literal in a database as do the original sets of rules. Previously, the rules were assumed to be function free. However, the use of universal quantifiers (corresponding to the division operator in a database) adds a new degree of flexibility in defining views. We propose a new inference rule, the substitution rule, to replace resolution in the compilation process. The substitution rule handles the embedded universal quantifiers correctly so that the compiled forms again derive all proper instances of the head literals.
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- Chang, C.L. and Lee, R.C.T., Symbolic Logic and Mechanical Theorem Proving, Academic Press, 1973.Google Scholar
- Clark, K. L., Negation as Failure, in: H. Gallaire and J. Minker (eds.), Logic and Databases, Plenum Press, 1978, pp. 235–260.Google Scholar
- Henschen, L. and Naqvi, S., On Compiling Queries in Recursive First-Order Databases, J. Assoc. Comput. Mach., 31(1):45–85 (Jan. 1984).Google Scholar
- Lee, S.H. and Henschen, L., Semantics and Indefiniteness of Existential Quantifiers in the Deductive Databases, Proceedings of the Annual Conference of the International Association of Knowledge Engineers, June 1989, pp. 132–151.Google Scholar
- Lloyd, J.W. and Topor, R.W., Making Prolog More Expressive, Journal of Logic Programming 1(3):225–240 (Oct. 1984).Google Scholar
- Reiter, R., Deductive Question Answering on Relational Databases, in: H. Gallaire and J. Minker (eds.), Logic and Databases, Plenum Press, 1978, pp. 149–177.Google Scholar
- Robinson, J., A Machine-Oriented Logic Based on the Resolution Principle, J. Assoc. Comput. Mach. 12(1):23–41 (January 1965).Google Scholar
- Topor, R.W., Keddis, T., and Wright, D.W., Deductive Database Tools, Technical Report 84/7 (Revised August 23, 1985), Department of Computer Science, University of Melbourne, 1985.Google Scholar