Thank you very much. Now it's clear to me and I'm one step further. Oliver On Monday, 20 December 2021 at 14:37:16 UTC+1 Holger Knublauch wrote:
> > On 2021-12-20 10:22 pm, olidru wrote: > > Thanks for you quick reply. The result of my SPARQL query describes the > violation. So, with your proposal the not existing part of the triples is > declared as violation. > > What makes me wonder is that in opposite the expressions in sh:property > doesn’t describe the violation. What’s the reason for this different > understanding? > > In all cases, the sh:condition shape describes the constraints that the > target nodes must fulfill. In the case of property constraints this is > quite intuitive, so if you say sh:hasValue :Value_1 then it will only apply > to nodes where that property has the given value. With SHACL-SPARQL > constraints, you formulate the constraints in a way that may be confusing > at first, because you have to state the patterns that are *not* supposed to > exist. So if the SPARQL query returns no result (rows) then all is fine and > the rule will fire. The reason for this design is that this enables SPARQL > queries to return more information about the violation, e.g. the focus node > (?this) and the value node (?value). > > Is this clearer now? > > Holger > > > Many thanks for your help! > Oliver > > On Monday, 20 December 2021 at 09:39:37 UTC+1 Holger Knublauch wrote: > >> Thanks for sending the details in a minimal executable format. Made it >> much easier to play around. >> >> The issue is that the sh:condition must apply to the focus node(s), which >> means that before a rule is applied, the focus node must not violate any >> constraints from the node shape that is the sh:condition. In your example, >> the sh:sparql constraint will be violated, because >> >> PREFIX : <http://example.org/ex#> <http://example.org/ex#> >> SELECT $this >> WHERE { >> $this :MyObjProp ?prop . >> } >> >> in SHACL means that it will produce a constraint violation for each >> result in the SELECT query. In your example data, it would produce one >> violation for each value of MyObjProp, of which there are plenty. >> >> Maybe you meant to say WHERE { FILTER NOT EXISTS { $this :MyObjProp >> ?anyProp } } instead, to check that the focus node has *no* value for that >> property? >> >> HTH >> Holger >> >> >> On 2021-12-20 5:25 pm, olidru wrote: >> >> The example ontology has two classes (:MyClass and :Value) and two >> properties (:MyObjProp and :MyDataProp). >> :MyClass >> a owl:Class ; >> a sh:NodeShape ; >> rdfs:subClassOf owl:Thing ; >> . >> :MyDataProp >> a owl:DatatypeProperty ; >> rdfs:domain :MyClass ; >> rdfs:range xsd:string ; >> . >> :MyObjProp >> a owl:ObjectProperty ; >> rdfs:domain :MyClass ; >> rdfs:range :Value ; >> . >> :Value >> a owl:Class ; >> rdfs:subClassOf owl:Thing ; . >> >> Some instances were added. >> :MyClass_1 >> a :MyClass ; >> :MyDataProp :Value_1 ; >> :MyObjProp :Value_1 ; . >> :MyClass_2 a :MyClass ; >> :MyObjProp :Value_2 ; >> . >> :Value_1 >> a :Value ; >> . >> :Value_2 >> a :Value ; >> . >> >> A NodeShape :NodeShapeRule with a sh:rule (:SPARQLRule_1) was created. >> This rule creates new triples. With the sh:condition the rule should be >> restricted to a subset of targets. >> :NodeShapeRule >> a sh:NodeShape ; >> sh:rule :SPARQLRule_1 ; >> sh:targetClass :MyClass ; >> . >> :SPARQLRule_1 >> a sh:SPARQLRule ; >> sh:condition :NodeShapeConditionSPARQL ; >> sh:construct """ >> PREFIX : <http://example.org/ex#> <http://example.org/ex#> >> CONSTRUCT { >> $this :MyDataProp \"New input\" . >> } >> WHERE { >> $this :MyObjProp ?p . >> } >> """ ; >> . >> >> For the restriction two equivalent NodeShapes were defined. The first >> constraint works with sh:property, the other uses sh:sparql. >> :NodeShapeConditionProperty >> a sh:NodeShape ; >> sh:property [ >> sh:path :MyObjProp ; >> sh:description "NodeShapeConditionProperty" ; >> sh:hasValue :Value_1 ; >> ] ; >> sh:targetClass :MyClass ; >> . >> :NodeShapeConditionSPARQL >> a sh:NodeShape ; >> sh:sparql [ >> sh:message "NodeShapeConditionSPARQL" ; >> sh:prefixes <http://example.org/ex> <http://example.org/ex> ; >> sh:select """ >> PREFIX : <http://example.org/ex#> <http://example.org/ex#> >> SELECT $this >> WHERE { >> $this :MyObjProp ?prop . >> } >> """ ; >> ] ; >> sh:targetClass :MyClass ; >> . >> >> While doing inferencing with Topbraid Composer I received different >> results for both solutions. Only the solution with sh:property provides >> the expected response. Please, can anyone explain me this behavior? >> :MyClass_1 :MyDataProp "New input" >> >> -- >> You received this message because you are subscribed to the Google Groups >> "TopBraid Suite Users" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/topbraid-users/09c459dd-d5e5-4e58-9a5a-a16b53c24605n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/topbraid-users/09c459dd-d5e5-4e58-9a5a-a16b53c24605n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> >> -- > You received this message because you are subscribed to the Google Groups > "TopBraid Suite Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/topbraid-users/9240a044-bfd4-4459-bc8d-6b3f83172480n%40googlegroups.com > > <https://groups.google.com/d/msgid/topbraid-users/9240a044-bfd4-4459-bc8d-6b3f83172480n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > -- You received this message because you are subscribed to the Google Groups "TopBraid Suite Users" group. 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