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SPARQL query cannot find page that should exist

Ask Time:2018-06-08T22:15:40         Author:Ubercoder

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I am writing a query in DBpedia live http://dbpedia-live.openlinksw.com/sparql/ to return details of well known people. As a test case, I know there exists a page for the Roman Emperor Nero at http://dbpedia.org/page/Nero but my query does not return a row for him. My SPARQL query is:

# Runs in live (http://dbpedia-live.openlinksw.com/sparql/)
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX dbo: <http://dbpedia.org/ontology/>
SELECT DISTINCT ?x0 ?name2 ?dob 
WHERE {
  ?x0 rdf:type foaf:Person.
  ?x0 rdfs:label ?name.
  ?x0 dbo:birthDate ?dob.
  FILTER REGEX(?name,"^Ner.*","i").
  BIND (str(?name) AS ?name2)
} ORDER BY ?name2 LIMIT 100

I checked the page http://dbpedia.org/page/Nero and it has the rdf:type, rdfs.label and dbo.birthDate properties referenced in my query. When I run the above query it returns 100 other people with name beginning "Ner" using the case insensitive version of REGEX.

So my question is: Why does the above query not return Nero in the list of results?

Author:Ubercoder,eproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article:https://stackoverflow.com/questions/50762623/sparql-query-cannot-find-page-that-should-exist
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