Usage of rules in SPARQL queries - sparql

I would like to use rules in my ontology so that at the moment of the inference I can retrieve some information not explicitly expressed in the triplestore.
I created a basic ontology and I want to add this rule:
Person(?p) ^ hasSibling(?p, ?s) ^ Man(?s) → hasBrother(?p, ?s)
The SPARQL query I would like to perform is
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX owl: <http://www.w3.org/2002/07/owl#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
PREFIX prova: <http://www.example.it/prova/>
SELECT ?subject ?object
WHERE { ?subject prova:hasBrother ?object }
Running this does not return anything. Of course, I have created the individuals for each class, but I have not created the instance that involves hasBrother, as this is what I want the intelligence to retrieve by itself.
So, my question is: is it possible to use SPARQL queries to achieve inference described by rules? Or these kind of inferences are only possible with a dedicated query system? In protegè I learn about the SQWRL tab for instance.
I am using the last version of Protegè (5.5.0) and the last version of the SWRL Rules plugin (2.11). I have defined the rule in the SWRL Tab. Then I tried the SQWRL tab to perform the query, but I get a strange error related to "invalid query name", which I don't really understand. Any suggestion about this second point would be helpful.

Related

Construct loop in SPARQL

The following SPARQL query
PREFIX owl: <http://www.w3.org/2002/07/owl#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
prefix skos: <http://www.w3.org/2004/02/skos/core#>
prefix msc: <http://msc.org/resources/MSC/msc2020/>
construct {?s skos:broader msc:00-XX . }
where
{
?s a skos:Concept ; skos:notation ?notation.
filter regex (?notation, "00-\d\d")
}
searches all notations 00-01, 00-02, etc. and constructs a relation to the top level class 00-XX. However, this is only the first of 63 top level classes altogether, so I would like to "loop" over all top level classes automatically. On top, I would like to adapt this to other patterns. Is there a way to do this with SPARQL? If not, what would you recommend instead?
In the meantime we found a solution without SPARQL.
The SPARQL CONSTRUCT query was supposed to create a skos:broader relation between a skos:Concept with a notation like "00-01" (and all other concepts with 00-\d\d notation) and its proper subordinate concept, which for 00-01 is the skos:Concept with the notation 00-XX.
The data originate from a table and Open Refine is much faster in creating the skos:broader statements than using the SPARQL query proposed above and adjusting it to other notation patterns.
We use GREL's value.replace on the cells with the notations to create a new column:
value.replace(/-\d\d/, "-XX").replace(/\d\d>/, "xx>")
The two replacements give us the notation of the original notation's superordinate concept in one step. The second replace already adapts to the other patterns mentioned in the question (e.g. 00A01).
With the original notation and the value in the new column, we can easily create the skos:broader triples by concatenating text and the values from both columns. These can then be exported from OpenRefine and just be copy-pasted to our SKOS vocabulary.
Here is a SPARQL answer based on the query in the question. Using filters and regex (as suggested in the comment by Yahalnaut as a reply to UninforomedUser above) is needed. Creating a skos:broader relation based on two concept's notations requires them to hava an identical sequence of digits before the - . The comparison should only between the first part of the notations, so each 00- should match another 00-but not a 01-. As asked, the solution below only considers topConcepts of the Vocabulary as potential objects for skos:broader. The concepts should also not relate to themselves, therefore the last filter. This should then be adoptable to other patterns as well. Depending on the number of Concepts and the memory available for the query, this may last a while or even stop before finished. It eliminates lot of the effort though.
PREFIX owl: <http://www.w3.org/2002/07/owl#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
prefix skos: <http://www.w3.org/2004/02/skos/core#>
prefix msc: <http://msc.org/resources/MSC/msc2020/>
construct {?s skos:broader ?y . }
where {
?s a skos:Concept ; skos:notation ?notation.
?y skos:topConceptOf msc: ; skos:notation ?not2.
bind (REPLACE (?not2 , "-XX" , "") as ?1)
bind (REPLACE (?notation , "-\d\d", "" ) as ?2 )
filter (?1 = ?2)
filter (?not2 != ?notation)
}

How to list all properties on a custom Wikibase instance

I am trying to list all properties created in on a wikibase I installed, using docker-compose, based on this install.
Now, want to list all properties that are available in this wikibase, similar to getting that list available through:
<wikibase.url>wiki/Special:ListProperties
I have also extracted that list through SPARQL with the following SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
PREFIX wikibase: <http://wikiba.se/ontology#>
PREFIX schema: <http://schema.org/>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
SELECT DISTINCT
?property
?propertyType
?propertyLabel
?propertyAltLabel
WHERE {
?property a wikibase:Property ;
rdfs:label ?propertyLabel ;
wikibase:propertyType ?propertyType .
OPTIONAL {?property skos:altLabel ?propertyAltLabel .}
}
Running that SPARQL query is expensive though and I need to run that query often, so I would very much like to get that list of properties to the core wikibase API.
Is that possible?
If you know the namespace number for properties on the target wiki (it’s usually 122 if the wiki has an Item: namespace, or 120 if, like on Wikidata, items are in the main namespace), you can use the core allpages API: https://www.wikidata.org/w/api.php?action=query&list=allpages&apnamespace=120
To also get the labels at the same time, use it as a generator and combine it with the entityterms API (new in 1.35; looks like it’s not documented yet, but see T257658): https://www.wikidata.org/w/api.php?action=query&generator=allpages&gapnamespace=120&prop=entityterms&wbetterms=label

skos broader and narrow inverse not working

I have setup GraphDB SE trial version and trying out inference functionality with OWL2-RL ruleset. I have built a simple SKOS knowledge with a single broader relationship. Some how, when I try to query for narrower relationship am not getting any results. Am I going wrong in the usage ?
Insertion:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
PREFIX owl: <http://www.w3.org/2002/07/owl#>
INSERT DATA {
ex:mammals rdf:type skos:Concept;
skos:prefLabel "mammals"#en;
ex:animals rdf:type skos:Concept;
skos:prefLabel "animals"#en;
skos:broader ex:mammals .
}
Query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
select * where {
?s skos:narrower ?o .
}
In the query result I don't see any response. Shouldn't it return below result -
ex:mammals skos:narrower ex:animals
I just came across this question and the OP is correct: Although the official SKOS reference explicitly states that skos:broader and skos:narrower are inverse, the actual RDF implementation does not include this statement. However, properties skos:broaderTransitive and skos:narrowerTransitive are declared as inverse.
And, although not relevant to the original question, the implementation does not state properties skos:topConceptOf and skos:hasTopConcept as inverse either.

fuseki doesn't select from dbpedia on my computer

I have fuseki running on my computer. version 1.1.1. but it when I enter a query to select from dbpedia it doesnt return anything. The query made is suppose to return http://dbpedia.org/class/yago/Guitarist110151760 as ?artistKind and http://semanticweb.org/laura/ontologies/2014/9/untitled-ontology-26#Guitar as ?instrument.
I made the ontology in protege and used a restriction that Guitarist110151760 playsInstrument Guitar.
PREFIX instru: <http://www.semanticweb.org/laura/ontologies/2014/9/untitled-ontology-26#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX dbpedia: <http://dbpedia.org/resource/>
select ?artistKind ?instrument
FROM <http://www.semanticweb.org/laura/ontologies/2014/9/untitled-ontology-26#>
WHERE
{
?artistKind instru:playsInstrument ?instrument.
SERVICE <http://dbpedia.org/sparql> {
dbpedia:Eric_Clapton rdf:type ?artistKind . }
}
Use website http://dbpedia.org/sparql to perform successful queries on dbpedia ontology because jena fusiki is used to perform queries on local ontologies inside hard disk (by loading owl files)

PROTÉGÉ SPARQL QUERY TAB: cannot query for ontology-specific classes

I am using SPARQL Query tab in Protege 5 to query an OWL ontology I have been constructing. I succeded in many kinds of queries, but when I use some specific class of my ontology inside the very same queries (that are apparently well formed) they return no results. Following, two of the problematic queries - assuming "Event" as one of the concepts of the ontology (http://www.semanticweb.org/ontologies/2014/5/MyOnto#Event):
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX owl: <http://www.w3.org/2002/07/owl#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX onto: <http://www.semanticweb.org/ontologies/2014/5/MyOnto#>
SELECT ?a WHERE { ?a rdfs:subClassOf onto:Event }
and, with the same prefixes
SELECT ?a WHERE { ?a rdfs:range onto:Event }
Both return no results. However, if I substitute "onto:Event" for, let's say, ?b, both return a long list of results - inclunding Event as a match for ?b.
Is it something I'm misusing or forgetting (although I've seen this pattern in several links on internet with people claiming to have got results) or is it a limitation of SPARQL or some issue of the Protege tab?
The problem is that, in fact, although the URI of the ontology is:
<http://www.semanticweb.org/ontologies/2014/5/MyOnto#>
in the OWL document, the prefix used before class names is the IRI:
<http://www.semanticweb.org/ontologies/2014/2/untitled-ontology-662#>
Thus, replacing the old onto: by
PREFIX onto: <http://www.semanticweb.org/ontologies/2014/2/untitled-ontology-662#>
solves the issue.
(Thanks to #Csongor from Protégé Project mail list, who found the answer.)
P.S.: It's also worthy to note that it can't be taken for granted that all the terms in the ontology will be <current_ontology_URI#term> - e.g. if one includes some terms in the ontology and then changes ontology URI, these terms will be identified as <previous_ontology_URI#term> and the new ones as <current_ontology_URI#term> (which was exactly the cause of the problem above).
I had the same problem, whenever using an ontology specific class there were no results although there should have been. My ontology (pizza.owl) was loaded from a local file.
I found that it is required to add the file name in the PREFIX.
PREFIX : <http://www.co-ode.org/ontologies/pizza/pizza.owl#>
After that I got the information that I expected.