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Queries using DESCRIBE

Like CONSTRUCT, DESCRIBE delivers as output an RDF graph – i.e., a set of RDF triples. It differs from CONSTRUCT in that these triples are not constructed according to a template, but returned as found in the dataset.

The reasons for doing this are similar to those for CONSTRUCT – you might, for instance, want to add these triples to another dataset – but you would prefer DESCRIBE if you were satisfied with the original encoding and had no reason to re-express the information using different resource names.

To specify the desired information, the simplest method is to name a resource; the query engine will then return all triples in which this resource is employed either as subject, predicate or object. Thus the following query will retrieve all statements mentioning Paul McCartney.

PREFIX dbpedia: <http://dbpedia.org/resource/>

DESCRIBE dbpedia:Paul_McCartney

Alternatively, resources can be specified more generically as bindings to a variable. Thus the following query requests all triples that mention a member of the Beatles.

PREFIX dbpedia: <http://dbpedia.org/resource/>
PREFIX mo: <http://purl.org/ontology/mo/>

DESCRIBE ?member
WHERE { dbpedia:The_Beatles mo:member ?member }

This work is a derivative of ‘Using Linked Data Effectively’ by The Open University (2014) and licensed under CC by 4.0 International Licence adapted and used by the University of Southampton. http://www.euclid-project.eu/

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