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sparqlowlwikidata-query-service

Solving 3x3 Sudoku with SPARQL and OWL

I'm trying to solve simple 3x3 Sudoku game inside query.wikidata.org using SPARQL and OWL.

3x3 Sudoku game

PREFIX owl: <http://www.w3.org/2002/07/owl#>
SELECT ?a12 ?a13 ?a21 ?a23 ?a31 ?a32 WHERE{

:Zahl a owl:Class;
        owl:oneOf (:1 :2 :3) .

 
?a12 a :Zahl.
?a13 a :Zahl.
?a21 a :Zahl.
?a23 a :Zahl.
?a31 a :Zahl.
?a32 a :Zahl.
       
?a11 owl:sameAs :1.
?a22 owl:sameAs :2.
?a33 owl:sameAs :3.

?a12 owl:differentFrom ?a11 ?a13 ?a22 ?a32.
?a13 owl:differentFrom ?a11 ?a12 ?a23 ?a33.
?a21 owl:differentFrom ?a22 ?a23 ?a11 ?a31.
?a23 owl:differentFrom ?a22 ?a21 ?a13 ?a33.
?a31 owl:differentFrom ?a11 ?a21 ?a32 ?a33.
?a32 owl:differentFrom ?a12 ?a22 ?a31 ?a33.
}

But i get this error:

Query is malformed: Encountered " <PNAME_LN> "owl:oneOf "" at line 5, column 19.

Could somebody please point out my mistake?

Solution

  • Hello my fellow friend from Karlsruhe,

    your basic mistake is that you try to define objects in your query - :Zahl a owl:Class; owl:oneOf (:1 :2 :3) .

    The query is not the place for that. This can only be done in the rdf document - which should not be changed in the exercise. Another mistake is a wrong understanding of objects and literals: ...owl:oneOf (:1 :2 :3) . ... ?a11 owl:sameAs :1. ?a22 owl:sameAs :2. ?a33 owl:sameAs :3.

    owl:sameAs does not wirk on literals, so these are objects named 1, 2, and 3. You could work with objects named 1,2,3, but it is a lot easier to work with numbers (literals) and use filters (FILTER (?a11 = 1)).

    Based on our source rdf, i think this is the way things should be done, as these are defined literals: ex:field ex:allowed "1"^^xsd:int, "2"^^xsd:int, "3"^^xsd:int. Cheers!