Equivalences of logic programs
For applications such as deductive databases employing the Open World Assumption, failed derivations have a lesser importance. In this case, use of the identical equivalences based upon the functional semantics [P] and the logical consequences of P allows the application of two different and powerful tools to reason about programs. In particular, these equivalences seem ideal for discussing the deductive structure of such deductive databases, independent of any particular state of the database of facts.
When negation-as-failure is used in evaluating queries, the equivalence of completed programs is more appropriate. This equivalence is only slightly stronger than (high level) operational equivalence and the well-developed formalism of logic is available to facilitate reasoning about programs.
KeywordsLogic Program Function Symbol Predicate Symbol Horn Clause Ground Atom
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