DBpedia: Query All information about a specific resource with SPARQL - sparql

If I have a dbpedia url (i.e., http://dbpedia.org/page/Idris_Elba), how can I query SPARQL to return all dob & foaf information and to verify if the entity (in this case Idris Elba) is a person? true/false
Current Query
PREFIX dbpedia: <http://dbpedia.org/resource/>
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
select * {
values ?person { dbpedia:Idris_Elba}
?person ?p ?o
}

Related

Querying dbpedia, not getting expected result not sure what's the mistake

My query is
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX dbp: <http://dbpedia.org/property/>
SELECT ?craft where
{
?craft <http://dbpedia.org/property/title> ?v.
}
Now this returning lot of results,
but nothing related to Steve Jobs or Tim Cook, even though in their page there is a property named title.
dbp:title dbr:List_of_Apple_Computer_CEOs
http://dbpedia.org/page/Steve_Jobs

The query:
PREFIX dbp: <http://dbpedia.org/property/>
SELECT (COUNT(*) AS ?nb_result)
WHERE {
?craft dbp:title ?v .
}
returns:
nb_result
---------
1566113
The public query endpoint for DBpedia limits the number of results to 10,000, among other restrictions. So your chances of retrieving any specific statement there are very small. If you worry that the data at the query endpoint is different than at the front end, you can check that the data is there with the query:
PREFIX dbp: <http://dbpedia.org/property/>
PREFIX dbr: <http://dbpedia.org/resource/>
SELECT ?prop ?value
WHERE {
dbr:Steve_Jobs ?prop ?value .
}
and compare with what's displayed at http://dbpedia.org/page/Steve_Jobs.

Different order of results in DBpedia through SNORQL vs. SERVICE query

I am trying to retrieve some data about movies from DBpedia. This is my query:
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 rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX dc: <http://purl.org/dc/elements/1.1/>
PREFIX : <http://dbpedia.org/resource/>
PREFIX dbpedia2: <http://dbpedia.org/property/>
PREFIX dbpedia: <http://dbpedia.org/>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
PREFIX onto: <http://dbpedia.org/ontology/>
PREFIX dcterms: <http://purl.org/dc/terms/>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
SELECT *
{{SELECT *
WHERE {
SERVICE<http://dbpedia.org/sparql>{
?movie dcterms:subject <http://dbpedia.org/resource/Category:American_films> ;
a onto:Film ;
rdfs:label ?title ;
dbpedia2:gross ?revenue .
?movie onto:starring ?actorUri .
?actorUri rdfs:label ?actor .
OPTIONAL {
?movie onto:imdbId ?imdbId .
}
BIND(xsd:integer(?revenue) as ?intRevenue) .
FILTER ((datatype(?revenue) = 'http://dbpedia.org/datatype/usDollar') && (LANGMATCHES(LANG(?title), 'en')) && (LANGMATCHES(LANG(?actor), 'en'))) .
}
}
}}
ORDER BY DESC (?intRevenue)
LIMIT 40000
OFFSET 0
Running this query on http://dbpedia.org/snorql/ (without the SERVICE keyword) returns the correct result. However, doing so from a third party triplestore doesn't yield the same order (ex: Hobbit and Lord of the Rings are missing).
What do I need to change in the query to get identical results?

The best way to overcome this specific limitation is to have your own DBpedia mirror, on which you can set your own limits (including none), and which you can then use as either your primary or remote data store and/or query engine.
(ObDisclaimer: OpenLink Software provides the public DBpedia SPARQL endpoint, produces Virtuoso and the DBpedia Mirror AMI, and employs me.)

SPARQL query to get all Person available in DBpedia is showing only some Person data, not all

I am writing SPARQL query to get all Person available in DBpedia. My query is ->
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbp: <http://dbpedia.org/property/>
SELECT ?resource ?name
WHERE {
?resource rdf:type dbo:Person;
dbp:name ?name.
FILTER (lang(?name) = 'en')
}
ORDER BY ASC(?name)
It's giving around 10000 rows,when I am taking the output as HTML/csv/spreadsheet format.
But when I am giving query to get total count
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbp: <http://dbpedia.org/property/>
SELECT COUNT(*)
WHERE{
?resource rdf:type dbo:Person;
dbp:name ?name.
FILTER (lang(?name) = 'en')
}
It's giving -> 1783404
Can anyone suggest a solution to get all rows of Person available in DBpedia?

DBPedia is being smart enough here to not overload its servers with large queries, and capping matches at 10000. Since you are ordering the results, you can use LIMIT and OFFSET to get result in sets of 10000. For example, to get the second set of 10000 results use this:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbp: <http://dbpedia.org/property/>
SELECT ?resource ?name
WHERE {
?resource rdf:type dbo:Person;
dbp:name ?name.
FILTER (lang(?name) = 'en')
}
ORDER BY ASC(?name)
LIMIT 10000 OFFSET 10000
Actually, since DBPedia is limiting the results to 10000 matches, the LIMIT isn't really necessary.

DBPedia SPARQL query should return results but is empty

I want to get all pages which have a specified category and a specified key. My query:
PREFIX dbpedia: <http://dbpedia.org/>
PREFIX dbpedia2: <http://dbpedia.org/property/>
PREFIX dbpedia-owl: <http://dbpedia.org/ontology/>
PREFIX dcterms: <http://dublincore.org/2010/10/11/dcterms.rdf#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX geo: <http://www.w3.org/2003/01/geo/wgs84_pos#>
PREFIX grs: <http://www.georss.org/georss/point>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
SELECT ?page ?cat ?key ?value (lang(?value) as ?language) WHERE {
?page dcterms:subject ?cat .
?page ?key ?value .
FILTER(
regex(?cat, "category:Amusement_parks_in_the_Netherlands") &&
?key = foaf:depiction
)
}
But it return zero results. See here: SNORQL query
It should at least return this page: http://dbpedia.org/page/Duinrell (because it matches the criteria).
Any ideas?

There's a couple of things wrong with your query. First of all, don't use a regex when comparing URIs. Instead of:
regex(?cat, "category:Amusement_parks_in_the_Netherlands")
use:
?cat = <http://dbpedia.org/resource/category:Amusement_parks_in_the_Netherlands>
Second: your namespace prefix for dublin core seems wrong. You are querying the property dcterms:subject, and in your query, the prefix dcterms is mapped to the namespace http://dublincore.org/2010/10/11/dcterms.rdf#. However, the actual property in DBPedia is http://purl.org/dc/terms/subject, so your namespace prefix should map to http://purl.org/dc/terms/ instead.

Getting a list of American physicists from DBpedia using SPARQL

I want to query the American Physicsts and get the list of physicists. How can I do this?

The SPARQL you need would look like this ....
PREFIX category: <http://dbpedia.org/resource/Category:>
PREFIX dcterms: <http://purl.org/dc/terms/>
SELECT *
WHERE {
?s dcterms:subject category:American_physicists .
}
see results here
If you want the list with some extra predicates you need to join more triple patterns using the variable ?s. For instance, to retrieve the birthdate for each physicist ...
PREFIX category: <http://dbpedia.org/resource/Category:>
PREFIX dcterms: <http://purl.org/dc/terms/>
PREFIX dbpedia: <http://dbpedia.org/ontology/>
SELECT *
WHERE {
?s dcterms:subject category:American_physicists .
?s dbpedia:birthDate ?bithdate .
}
results here