Evaluation of Declarative n-Queens Recursion: A Deductive Database Approach

Can we evaluate a logic program declaratively? That is, can a logic program be evaluated correctly and eeciently, independent of query modes and rule/predicate ordering, nding a complete set of answers, and terminating properly? The answer could be \yes", at least for a good subclass of logic programs, based on our investigation and experimentation using a deductive database approach. In this paper, an n-queens problem, a classical logic program, is used as a running example to demonstrate the methodology. Our analysis shows that binding analysis and constraint exploration are two essential issues in the realization of declarative logic programming. The limitations of our methodology are also discussed in the paper.