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From the 1 of 6 linked papers with an AI index.

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6 papers

cs.AI2026

Shapes from Examples: Foundations of Shape Learning in Recursive SHACL

Bente Gortworst, Cem Okulmus, Magdalena Ortiz +1

The paper studies automatic learning of SHACL shapes for knowledge graph validation by fitting positive and negative example nodes, focusing on a core SHACL fragment equivalent to…

cs.LO2026

Common Foundations for Recursive Shape Languages

Shqiponja Ahmetaj, Iovka Boneva, Jan Hidders +9

As schema languages for RDF data become more mature, we are seeing efforts to extend them with recursive semantics, applying diverse ideas from logic programming and description lo…

cs.DB2025

Selective Use of Yannakakis' Algorithm to Improve Query Performance: Machine Learning to the Rescue

Daniela Böhm, Georg Gottlob, Matthias Lanzinger +4

Query optimization has played a central role in database research for decades. However, more often than not, the proposed optimization techniques lead to a performance improvement…

cs.DB2025

Towards Practicable Algorithms for Rewriting Graph Queries beyond DL-Lite

Bianca Löhnert, Nikolaus Augsten, Cem Okulmus +1

Despite the many advantages that ontology-based data access (OBDA) has brought to a range of application domains, state-of-the-art OBDA systems still do not support popular graph d…

cs.DB2025

Soft and Constrained Hypertree Width

Matthias Lanzinger, Cem Okulmus, Reinhard Pichler +2

Hypertree decompositions provide a way to evaluate Conjunctive Queries (CQs) in polynomial time, where the exponent of this polynomial is determined by the width of the decompositi…

cs.DB2025

Common Foundations for SHACL, ShEx, and PG-Schema

S. Ahmetaj, I. Boneva, J. Hidders +11

Graphs have emerged as an important foundation for a variety of applications, including capturing and reasoning over factual knowledge, semantic data integration, social networks,…