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I'm trying to follow the example given in this answer on OWL reasoning in Blazegraph, but the query:

select * where { 
  :John rdf:type ?type 
}

returns only:

type: owl:NamedIndividual, owl:Thing

but not the expected inference:

type: :Vegetarian

My namespace configuration in Blazegraph:

com.bigdata.namespace.kb.spo.com.bigdata.btree.BTree.branchingFactor    1024
com.bigdata.relation.container  test-owl
com.bigdata.journal.AbstractJournal.bufferMode  DiskRW
com.bigdata.journal.AbstractJournal.file    bigdata.jnl
com.bigdata.journal.AbstractJournal.initialExtent   209715200
com.bigdata.rdf.store.AbstractTripleStore.vocabularyClass   com.bigdata.rdf.vocab.DefaultBigdataVocabulary
com.bigdata.rdf.store.AbstractTripleStore.textIndex false
com.bigdata.btree.BTree.branchingFactor 128
com.bigdata.namespace.kb.lex.com.bigdata.btree.BTree.branchingFactor    400
com.bigdata.rdf.store.AbstractTripleStore.axiomsClass   com.bigdata.rdf.axioms.OwlAxioms
com.bigdata.rdf.sail.isolatableIndices  false
com.bigdata.service.AbstractTransactionService.minReleaseAge    1
com.bigdata.rdf.sail.truthMaintenance   true
com.bigdata.journal.AbstractJournal.maximumExtent   209715200
com.bigdata.rdf.store.AbstractTripleStore.justify   true
com.bigdata.rdf.sail.namespace  test-owl
com.bigdata.relation.class  com.bigdata.rdf.store.LocalTripleStore
com.bigdata.rdf.store.AbstractTripleStore.quads false
com.bigdata.relation.namespace  test-owl
com.bigdata.btree.writeRetentionQueue.capacity  4000
com.bigdata.rdf.store.AbstractTripleStore.statementIdentifiers  false

What am I missing?

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igor.br
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  • In the link you mentioned it's said that Blazegraph does not support OWL reasoning out of the box. So what do you expect? Do have OWL reasoning enabled? Does such an option exist? – UninformedUser Jun 16 '16 at 06:33
  • I understood the link so that the desired inference will be achieved with the given Blazegraph configuration since the parameter axiomsClass is set here to OwlAxioms. Isn't? Did I misunderstand this? – igor.br Jun 16 '16 at 18:29
  • I never used Blazegraph, but when I look into the docs at https://wiki.blazegraph.com/wiki/index.php/InferenceAndTruthMaintenance they say "It's not full RDFS (e.g. rules RDFS4a and RDFS4b are disabled by default) nor OWL. It is meant to be a useful set of inference rules, not corresponding directly to a standard." – UninformedUser Jun 16 '16 at 19:35
  • Moreover, the docs state that for full RDFS or OWL RL you have to take by yourself. Your example needs inference based on existential restrictions. Not sure if this Blazegraph built-in https://blazegraph.github.io/database/apidocs/com/bigdata/rdf/axioms/OwlAxioms.html covers that. It's supposed to be a subset of OWL, but there is no complete information on what's exactly covered. – UninformedUser Jun 16 '16 at 19:39
  • Ok, you seem to be right. It was my delusion in understanding of the linked example. Thank you for support. – igor.br Jun 18 '16 at 12:15

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