On the Expressivity of ASK Queries in SPARQL


  • Xiaowang Zhang Tianjin University
  • Jan Van den Bussche Hasselt University
  • Kewen Wang Griffith University
  • Heng Zhang Tianjin University
  • Xuanxing Yang Tianjin University
  • Zhiyong Feng Tianjin University




As a major query type in SPARQL, ASK queries are boolean queries and have found applications in several domains such as semantic SPARQL optimization. This paper is a first systematic study of the relative expressive power of various fragments of ASK queries in SPARQL. Among many new results, a surprising one is that the operator UNION is redundant for ASK queries. The results in this paper as a whole paint a rich picture for the expressivity of fragments of ASK queries with the four basic operators of SPARQL 1.0 possibly together with a negation. The work in this paper provides a guideline for future SPARQL query optimization and implementation.




How to Cite

Zhang, X., Bussche, J. V. den, Wang, K., Zhang, H., Yang, X., & Feng, Z. (2020). On the Expressivity of ASK Queries in SPARQL. Proceedings of the AAAI Conference on Artificial Intelligence, 34(03), 3057-3064. https://doi.org/10.1609/aaai.v34i03.5700



AAAI Technical Track: Knowledge Representation and Reasoning