PUBLICATION
ShEx2SPARQL: Translating Shape Expressions into SPARQL Queries
Type
Conference Paper
Year
2025
Authors
Research Area
Web Engineering
Event
25th International Conference on Web Engineering
Published in
25th International Conference on Web Engineering, Delft, Netherlands
ISBN/ISSN
print: 978-3-031-97206-5; online: 978-3-031-97207-2
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Abstract
The Shape Expressions (ShEx) Language provides a powerful tool for de-scribing and validating structures in RDF knowledge graphs. While Shape Expressions are primarily used for validation, they also describe graph struc-tures, enabling knowledge graph exploration. However, existing ShEx en-gines focus on validation rather than data exploration. In this paper, we in-troduce ShEx2SPARQL, an approach to systematically translate shape ex-pressions into corresponding CONSTRUCT, SELECT, or ASK SPARQL que-ries. This enables knowledge graph exploration based on already available ShEx schemas. Our approach imposes certain restrictions, notably the exclu-sion of recursive shape references, as SPARQL lacks sufficient support for recursive expressions. To evaluate our approach, we selected 292 Wikidata Entity Schemas, translated them into corresponding SPARQL queries and ex-ecuted them against the Wikidata SPARQL endpoint. The results confirm the feasibility of our approach, but also reveal performance issues when execut-ing complex SPARQL queries resulting from complex shapes with a multi-tude of constraints.