A query evaluation strategy for deductive databases with presence of negation based on HLPN

We present an optimized recursive query evaluation for deductive databases with the presence of negative literals, based on the deductive high-level Petri net (DHLPN) model. The syntax and semantics of this model are derived from high-level Petri nets. Such a model benefits from the control structure inherent to Petri nets allowing the capture of rules' stratification, in order to interpret without ambiguities, negative literals in rules, particularly during a recursive query evaluation.