Detecting Unsatisfiable Pattern Queries under Shape Expression Schema

Shiori Matsuoka, Nobutaka Suzuki

2020

Abstract

Among queries for RDF/graph data, pattern query is the most popular and important one. A pattern query that returns empty answer for every valid graph is clearly useless, and such a query is called unsatisfiable. Formally, we say that a pattern query q is unsatisfiable under a schema S if there is no valid graph g of S such that the result of q over g is nonempty. It is desirable that unsatisfiable pattern queries can be detected efficiently before being executed since unsatisfiable query may require much execution time but always reports empty answer. In this paper, we focus on Shape Expression (ShEx) as schema, and we propose an algorithm for detecting unsatisfiable pattern queries under a given ShEx schema. Experimental results suggest that our algorithm can determine the satisfiability of pattern query efficiently.

Paper Citation

in Harvard Style

Matsuoka S. and Suzuki N. (2020). Detecting Unsatisfiable Pattern Queries under Shape Expression Schema.In Proceedings of the 16th International Conference on Web Information Systems and Technologies - Volume 1: WEBIST, ISBN 978-989-758-478-7, pages 285-291. DOI: 10.5220/0010171602850291

in Bibtex Style

@conference{webist20,
author={Shiori Matsuoka and Nobutaka Suzuki},
title={Detecting Unsatisfiable Pattern Queries under Shape Expression Schema},
booktitle={Proceedings of the 16th International Conference on Web Information Systems and Technologies - Volume 1: WEBIST,},
year={2020},
pages={285-291},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0010171602850291},
isbn={978-989-758-478-7},
}

in EndNote Style

TY - CONF

JO - Proceedings of the 16th International Conference on Web Information Systems and Technologies - Volume 1: WEBIST,
TI - Detecting Unsatisfiable Pattern Queries under Shape Expression Schema
SN - 978-989-758-478-7
AU - Matsuoka S.
AU - Suzuki N.
PY - 2020
SP - 285
EP - 291
DO - 10.5220/0010171602850291