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GraphDB's Visual graph does not display all triples

In my graph I have the following assertions

  @prefix :     <http://www.example.org/~joe/contact.rdf#> .
  @prefix foaf: <http://xmlns.com/foaf/0.1/> .
  @prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

  :joesmith a foaf:Person ;
        foaf:givenname "Joe" ;
        foaf:family_name "Smith" ;
        foaf:homepage <http://www.example.org/~joe/> ;
        foaf:mbox <mailto:joe.smith@example.org> .

I loaded the graph in GraphDB.

If I point the GraphDB's Visual Graph to :joesmith, I would like to see all the triples but I see this graph

enter image description here

foaf:givenname and foaf:family_name are not shown in the graph but they are in node details tab, and it's ok.

Instead the node http://www.example.org/~joe/ is not connected to :joesmith. It seems pretty wired, since there is an explicit assertion belonging to :joesmith

Is this a bug or a problem in my data?

Solution

  • This is definitely a bug. This bug affects Visual Graph functionality only. In the SPARQL results view, everything is fine.

    The problem seems to be complex. There are two factors:

    • This namespace — <http://xmlns.com/foaf/0.1/> — is hardcoded somewhere.

    • This namespace is not proceeded correctly.

    Let us consider the following examples.
    Before each example, clear your repository and delete prefixes created in Setup > Namespaces.

    Case 1

    @prefix :     <http://www.example.org/~joe/contact.rdf#> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

  :joesmith a foaf:Person ;
        foaf:givenname "Joe" ;
        foaf:family_name "Smith" ;
        foaf:homepage <http://www.example.org/~joe/> ;
        foaf:mbox <mailto:joe.smith@example.org> .

    As you have pointed out, <http://www.example.org/~joe/> is not shown.

    Case 2

    @prefix :     <http://www.example.org/~joe/contact.rdf#> .
@prefix foo: <http://xmlns.com/foaf/0.1/> .
@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

  :joesmith a foo:Person ;
        foo:givenname "Joe" ;
        foo:family_name "Smith" ;
        foo:homepage <http://www.example.org/~joe/> ;
        foo:mbox <mailto:joe.smith@example.org> .

    In this case, <http://www.example.org/~joe/> is not shown.

    Case 3

    @prefix :     <http://www.example.org/~joe/contact.rdf#> .
@prefix foaf: <http://xmlns.com/foaf/01/> .
@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

  :joesmith a foaf:Person ;
        foaf:givenname "Joe" ;
        foaf:family_name "Smith" ;
        foaf:homepage <http://www.example.org/~joe/> ;
        foaf:mbox <mailto:joe.smith@example.org> .

    In this case, <http://www.example.org/~joe/> is shown.

    Case 4

    @prefix :     <http://www.example.org/~joe/contact.rdf#> .
@prefix foaf: <http://xmln.com/foaf/0.1/> .
@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

  :joesmith a foaf:Person ;
        foaf:givenname "Joe" ;
        foaf:family_name "Smith" ;
        foaf:homepage <http://www.example.org/~joe/> ;
        foaf:mbox <mailto:joe.smith@example.org> .

    In this case, <http://www.example.org/~joe/> is shown.

    I'll try to contact their support team directly by sending email.

    UPDATE 1

    They say there are four kinds of RDF terms:

    1. URIs
    2. Literals
    3. Blank nodes
    4. URIs considered by their team as "not real".

    From GraphDB query logs, one can ascertain what URIs are of the fourth kind.

    BIND (strstarts(str(?p), "http://purl.org/dc/terms/") ||
      strstarts(str(?p), "http://dbpedia.org/ontology/subsidiary") AS ?isMeta)
    FILTER(!strstarts(str(?p), "http://www.w3.org/2002/07/owl#")
              && !strstarts(str(?p), "http://www.w3.org/1999/02/22-rdf-syntax-ns#")
              && !strstarts(str(?p), "http://www.w3.org/2000/01/rdf-schema#")
              && !strstarts(str(?p), "http://www.openrdf.org/schema/sesame#")
              && !strstarts(str(?p), "http://www.ontologydesignpatterns.org/ont/dul/DUL.owl")
              && !strstarts(str(?p), "http://www.w3.org/ns/prov")
              && !strstarts(str(?p), "http://dbpedia.org/ontology/wikiPage")
              && !strstarts(str(?p), "http://dbpedia.org/property/wikiPage")
              && !strstarts(str(?p), "http://www.omg.org/spec/")
              && !strstarts(str(?p), "http://www.wikidata.org/entity/")
              && !strstarts(str(?p), "http://factforge.net/")
              && ?p != <http://dbpedia.org/property/logo>;
              && ?p != <http://dbpedia.org/property/hasPhotoCollection>;
              && ?p != <http://dbpedia.org/property/website>;
              && ?p != <http://dbpedia.org/property/homepage>;
              && ?p != <http://dbpedia.org/ontology/thumbnail>;
              && ?p != <http://xmlns.com/foaf/0.1/depiction>;
              && ?p != <http://xmlns.com/foaf/0.1/homepage>;
            )

    UPDATE 2

    In GraphDB 8.3, it was fixed in some way:

    GDB-2076 - Visual graph: consistent handling of foaf/dbpedia predicates that point to IRIs but are treated as literals