Questions tagged [semantic-web]

Representation of database record subjects (a/k/a keys, IDs, entities), predicates (a/k/a columns, attributes), and objects (a/k/a values) as triples, where the first two are always URIs, and the third is either a URI or a literal; enabling humans and machines to more easily share, merge, and evaluate data from heterogeneous origins.

The Semantic Web (Web 3.0) provides a common framework that allows data to be shared and reused across application, enterprise, and community boundaries. It is a collaborative effort led by the W3C with participation from a large number of researchers and industrial partners. It is based on the Resource Description Framework (RDF).

1956 questions
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Sparql- how to get number of triples?

I'm doing a small exercise on sparql. Using Dbpedia Endpoint, I need to count number of triples. This is my query // Get the number of triples // SELECT (COUNT(*) as ?Triples) WHERE { ?s ?p…
Aziz Mumtaz
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Good SPARQL query to find all triples with a resource as subject or object

I need to find all triples on DBpedia where http://dbpedia.org/resource/Benin is a subject or object. This query gives me the output that I want in a format that works the best for me (just three variables and no blank spaces): PREFIX :…
kurious
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How do I read .owl files in java and display its contents?

How do I read .owl files in java and display its contents?
nagender
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Multiple domain and range in objectProperty?

I want to create an ontology with Protege that contains two classes, Animal and FatherAnimal, and the object property hasFather, with domain Animal and range FatherAnimal. Also, I create two other classes: Son and Father which are linked with the…
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How to exclude resources with a specific rdf:type from SPARQL results?

I have this query SPARQL that I ran on it.dbpedia.org/sparql: select ?resource where { ?resource rdfs:label "Piemonte"@it } I get this result: http://it.dbpedia.org/resource/Categoria:Piemonte http://it.dbpedia.org/resource/Piemonte I would like…
Musich87
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Sparql query with Blank node can be complex

I read this blog article, Problems of the RDF model: Blank Nodes, and there's mentioned that using blank nodes can complicate the handling of data. Can you give me an example why using blank nodes is difficult to perform a SPARQL query? I do not…
Competo
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How to model opening hours in RDF

What is the most pragmatic way to model opening hours of a service, so that SPARQL queries would be able to query things that are open at a certain timestamp/during a certain time interval? Answers to this question should contain: example of an…
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How can you remove the XML schema datattype from sparql query?

Im running a sparql query on a file that contains RJ I want to return only the name i.e. 'RJ' but when i enter my query SELECT ?name FROM…
allyLogan
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How to markup "Related News" using microdata?

A news post would be like

Awesome News

bla bla bla...
What if I would like to include…
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Using GROUP BY, COUNT and SAMPLE in apache jena SPARQL

So I have an RDF schema that contains many "groups", and each of these groups has a "name", and contains a number of "elements". I need to select the name of every group, along with the number of elements for each. Here is a sample of a group RDF…
user641687
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What HTML 5 tag is best suited for pagination container?

I have a div with only pagination related content within it. What is the best element/tag to use? I looked into
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django RDF support?

I'm looking for a tool that would help to provide RDF support to Django projects. So far I've found two: django-rdf - last modification was 4 yesrs ago so it looks like a dead project. djubby - looks like a all-or-nothing project - either you…
mnowotka
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Boolean checks in SPARQL, check for existence of a statement

Let's say I have a triple store full of video metadata. A video can have an arbitrary selection of pre-defined tags, like this: v1 ex:hasTag A. v2 ex:hasTag B. v3 ex:hasTag A; ex:hasTag B. So for the sake of this example, there are only the two…
cyroxx
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How to create an ontology from raw data (CSV)?

I am modelling university data using an OWL ontology with relevant classes, object properties, etc. I have the university data lying in a simple text file (say CSV). I want to create ontologies using my model for these data. My questions are: Is…
marc
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loading rdf triples into virtuoso opensource

I'm trying to create a local mirror of LinkedGeoData.org from this dump. That's around 61,000,000 triples. Virtuoso is supposed to easily handle a lot more than that, but every single time it stops loading after around 40,000,000 triples. I'm using…
ailnlv
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