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I am using Brightstardb as a triplestore and "Polaris management tool for Brightstardb" for import RDF and run queries.

I imported this RDF to the triplestore:

@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .   
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .

@prefix : <http://www.sample.org/abc#> .

:dog a rdfs:Class .

Then I run this SPARQL query:

PREFIX declarations ... ... ...
...
ASK { :dog a rdfs:Class .  }

The result is TRUE.

But, when I run this query:

PREFIX declarations ... ... ...
...
ASK { :dog a rdfs:Resource .  }

The result is FALSE.

This last result seems incorrect, because by definition anything in RDF is a Resource, as stated in the specification.

I need a way to get included all the basic axioms of RDF and RDFS specs in my SPARQL queries, to use in a inference system. How can I do this? Do I have to explicitally type the implicit axioms?

Examples of basic axioms in the W3C specs:

rdf:Property a rdfs:Class .

Because Property is the Class of all RDF properties.

rdfs:subClassOf a rdf:Property .
rdf:type a rdf:Property .

Because subClassOf is a Property that relates 2 Classes between them and type is a Property that relate a Resource (Subject) with a Class (Object).

Ignotus
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    *"This last result seems incorrect, because by definition anything in rdf is a Resource, as stated in the specification."* -> By definition of the RDFS semantics, yes. But without reasoning supported by the triple store and then also enabled, those triples do not exist in the triple store. Thus, SPARQL only matches triples that do exist. – UninformedUser Dec 14 '17 at 15:09
  • *"I need a way to get included all the basic axioms of rdf and rdfs specs in my SPARQL queries, to use in a inference system."* -> It would be the task of the inference system to infer those triples. If you mean the axiomatic triples, those can be loaded from https://www.w3.org/2000/01/rdf-schema# and http://www.w3.org/1999/02/22-rdf-syntax-ns# indeed. But this won't help, the RDF/RDFS rules have to be applied by some rule engine/reasoner. – UninformedUser Dec 14 '17 at 15:12
  • Thank you AKSW, it helps me. I think that maybe I can do some kind of reasoning with SPARQL on demand. – Ignotus Dec 14 '17 at 17:44

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