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In the neo4j quick queries pane, there are "relationship types" and "property keys" which make sense in the context of the Neo4j cypher query syntax.

In SPARQL, is there a way to distinguish between triples that are relationship and triples that are properties?

I suppose some example data could be like the following:

<actor12> <http://some.ontology.com/#ActedIn> <movie45>           #relationship
<movie45> <http://some.ontology.com/#title> “Gone with the Wind"  #property key/val
Kristian
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3 Answers3

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SPARQL is a query language targeting a specific data model, the one defined by RDF data. Usually, it is used to query either RDF or OWL data.

RDF defines properties without distiguishing them in object refering properties and data referencing properties. You could distinguish them indirectly by checking their range. If their range is an XSD property, then you could infer that it is a data referencing property.

OWL actually makes a formal distinguishment between the two kinds of properties. These are called, object properties and data properties. Therefore, if you use an OWL datamodel you could identify the type of the property directly by their OWL class. The ones you call "relationship types" are actually "object properties" and the ones you call "property keys" are "data properties" in OWL terminology. They are respectively identified as instances of owl:ObjectProperty and owl:DatatypeProperty class.

Hope I helped!

Pantelis Natsiavas
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You can check the data with a test for whether the object is a literal:

   ?s ?p ?o 
   FILTER (isLiteral(?o) )
AndyS
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  • could you elaborate a bit? – Kristian Jan 16 '14 at 23:05
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    @Kristian What you're calling property keys would have RDF literals as values, as opposed to URIs or blank nodes. If search for `?s ?p ?o` and only accept matches where `?o` is a literal, then each `?p` would be a datatype property (in OWL). Actually, this isn't quite true, since annotation properties could also have literal values, but the idea is there: if you look for properties that have literal values, then you'll find the properties that have literal values. – Joshua Taylor Jan 17 '14 at 01:53
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Pantelis Natsiavas rightly points out that in OWL you can distinguish object and datatype properties. You asked about how to do this in SPARQL. owl:DatatypeProperty and owl:ObjectProperty are RDFS classes, and so you can query about whether things are instances of them. For instance, you can ask for data properties from DBpedia:

select ?property where { 
 ?property a owl:DatatypeProperty
}
limit 10

SPARQL results

Community
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Joshua Taylor
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