The Alexander Method - a technique for the processing of recursive axioms in deductive databases
We propose a technique for handling recursive axioms in deductive databases. More precisely, we solve the following problem: Given a relational query including virtual relations defined from axioms (Horn clauses, with variables in the conclusion predefined in the hypotheses), which can be recursive, how to translate this query into a relational program, i.e. a set of relational operations concerning only real relations (not virtual). Our solution has the following properties: (1) the program to evaluate the query always terminates, (2) the relational program is produced by a pure compilation of a source query and of the axioms, and is independent of the data values (there is no run-time), (3) the relational operations are optimized: they focus towards the computation of the query, without needless computations. As far as we know, the Alexander Method is the first solution exhibiting all these properties.
scientific article; zbMATH DE number 3997191