Imagine you do something crazy and store your object-oriented model as an RDF graph.
shows a simplified example of the inheritance hierarchy and the associated attributes.
In practice, you get such graph structure if you translate some UML class diagram into RDFS.
The question is: what SPARQL query can deliver all the predicate-object pairs necessary to instantiate a particular resource of "Class C". In other words: how do you get all the predicate-object pairs along the whole inheritance chain (only single inheritance).
Given this diagram, the predicate-object pairs of all members of the class :ClassC
is simply:
SELECT ?inst ?p ?o
WHERE {
?inst a :ClassC .
Inst ?p ?o .
Keep in mind that there is not property inheritance in RDF/RDFS. If you want to find all of property/values pairs for ClassA
with entailments for subclasses then useL
SELECT ?inst ?p ?o
WHERE {
?cls rdfs:subClassOf* :ClassA .
?inst a ?cls .
?inst ?p ?o
}
In this respect, RDFS works a bit backwards of one's expectations of OO inheritance.
With the info from @scotthenninger the following query did the job:
SELECT ?p ?o
WHERE {
:ClassC rdfs:subClassOf* ?anySuperClass .
?anySuperClass ?p ?o .
}
edit: Similar query gets all the self-defined properties and their range along the inheritance chain:
SELECT ?prop ?obj
WHERE {
:ClassC rdfs:subClassOf* ?anySuperClass .
?prop rdfs:domain ?anySuperClass .
?prop rdfs:range ?obj .
}
End results combined:
foo:ID xsd:string
foo:name xsd:string
rdfs:comment xsd:string
foo:similarTo :ClassD
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.