Taming Existence in RDF Querying

Authors:
François Bry;Tim Furche;Clemens Ley;Benedikt Linse;Bruno Marnette
Affiliations:
Institute for Informatics, University of Munich, München, Germany D-80538;Institute for Informatics, University of Munich, München, Germany D-80538;Oxford University Computing Laboratory, Oxford, England OX1 3QD;Institute for Informatics, University of Munich, München, Germany D-80538;Oxford University Computing Laboratory, Oxford, England OX1 3QD
Venue:
RR '08 Proceedings of the 2nd International Conference on Web Reasoning and Rule Systems
Year:
2008

Citing 3
Cited 0

Data Exchange: Semantics and Query Answering

ICDT '03 Proceedings of the 9th International Conference on Database Theory
From SPARQL to rules (and back)

Proceedings of the 16th international conference on World Wide Web
Networked graphs: a declarative mechanism for SPARQL rules, SPARQL views and RDF data integration on the web

Proceedings of the 17th international conference on World Wide Web

Quantified Score

Hi-index	0.00

Visualization

Abstract

We introduce the recursive, rule-based RDF query language RDFLog. RDFLog extends previous RDF query languages by arbitrary quantifier alternation: blank nodes may occur in the scope of all, some, or none of the universal variables of a rule. In addition RDFLog is aware of important RDF features such as the distinction between blank nodes, literals and URIs or the RDFS vocabulary. The semantics of RDFLog is closed (every answer is an RDF graph), but lifts RDF's restrictions on literal and blank node occurrences for intermediary data. We show how to define a sound and complete operational semantics that can be implemented using existing logic programming techniques. Using RDFLog we classify previous approaches to RDF querying along their support for blank node construction and show equivalence between languages with full quantifier alternation and languages with only *** *** rules.