Query Answering with Guarded Existential Rules under Stable Model Semantics


  • Hai Wan Sun Yat-sen University
  • Guohui Xiao Free University of Bozen-Bolzano
  • Chenglin Wang Sun Yat-sen University
  • Xianqiao Liu Sun Yat-sen University
  • Junhong Chen Sun Yat-sen University
  • Zhe Wang Griffith University




In this paper, we study the problem of query answering with guarded existential rules (also called GNTGDs) under stable model semantics. Our goal is to use existing answer set programming (ASP) solvers. However, ASP solvers handle only finitely-ground logic programs while the program translated from GNTGDs by Skolemization is not in general. To address this challenge, we introduce two novel notions of (1) guarded instantiation forest to describe the instantiation of GNTGDs and (2) prime block to characterize the repeated infinitely-ground program translated from GNTGDs. Using these notions, we prove that the ground termination problem for GNTGDs is decidable. We also devise an algorithm for query answering with GNTGDs using ASP solvers. We have implemented our approach in a prototype system. The evaluation over a set of benchmarks shows encouraging results.




How to Cite

Wan, H., Xiao, G., Wang, C., Liu, X., Chen, J., & Wang, Z. (2020). Query Answering with Guarded Existential Rules under Stable Model Semantics. Proceedings of the AAAI Conference on Artificial Intelligence, 34(03), 3017-3024. https://doi.org/10.1609/aaai.v34i03.5695



AAAI Technical Track: Knowledge Representation and Reasoning