Ok so i have this query
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
SELECT DISTINCT (COUNT(?instance) AS ?count) WHERE {
?instance a <http://dbpedia.org/ontology/Ambassador> .
}
and the result is 286. Cool. Now I want to get the number of ambassadors that have http://dbpedia.org/property/name property. But
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
SELECT DISTINCT (COUNT(?instance) AS ?count) WHERE {
?instance a <http://dbpedia.org/ontology/Ambassador> .
?instance <http://dbpedia.org/property/name> ?name
}
results in 533 :(. So it is counting more because there are people which have this property one or more times. But how do I get the number of ambassadors that have this property regardless of how many times they have it. Can you do this in a single query?
Thanks.
You might want to try this:
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
SELECT (COUNT(DISTINCT ?instance) AS ?count) WHERE {
?instance a <http://dbpedia.org/ontology/Ambassador>;
<http://dbpedia.org/property/name> ?name
}
It's giving me a result of 283, which might or might not be right :).
Related
I am using live Dbpedia (http://dbpedia-live.openlinksw.com/sparql/) to get basic details of notable people. My query is:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX dbpedia-owl: <http://dbpedia.org/ontology/>
SELECT DISTINCT ?x0 ?name ?dob WHERE {
?x0 rdf:type foaf:Person.
?x0 rdfs:label ?name.
?x0 dbpedia-owl:birthDate ?dob.
FILTER REGEX(?name,"^[A-Z]","i").
} LIMIT 200
This works and I use LIMIT 200 to limit the output to a small number of people. My problem is the 200 people are random, and I want some way of measuring 'notability' such that I return 200 notable people, rather than 200 random people. There are over 500,000 people in Dbpedia.
My question is, how can I measure 'notability' and limit the query to return notable people only? I realize there is no 'notability' property and it is very subjective. I am happy to use any indirect or approximate measure such as number of links or number of references. But I don't know how to do this.
Edit : As a result of the helpful comments I improved the query to include page ranks:
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/>
PREFIX vrank:<http://purl.org/voc/vrank#>
SELECT DISTINCT ?s ?name2 ?dob ?v
FROM <http://dbpedia.org>
FROM <http://people.aifb.kit.edu/ath/#DBpedia_PageRank>
WHERE {
?s rdf:type foaf:Person.
?s rdfs:label ?name.
?s dbo:birthDate ?dob.
?s vrank:hasRank/vrank:rankValue ?v.
FILTER REGEX(?name,"^[A-Z].*").
BIND (str(?name) AS ?name2)
} ORDER BY DESC(?v) LIMIT 100
The problem now is there are lots of duplicates, even though I am using DISTINCT.
I'm very new in OpenData and try to write a query in SPARQL.
My goal is to get data for following set of criteria:
- Category: Home_automation
- select all items from type "Thing"
- with at least one entry in "is Product of"
- that have a picture-url with a German description
I tried the following:
PREFIX cat: <http://dbpedia.org/resource/Category:>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
SELECT *
WHERE {
cat:Home_automation skos:broader ?x
}
But now I don't know how to add the other filters to the where clause.
I tried to user broader:... to get the items, but I think that was the wrong direction.
I tested the queries with: https://dbpedia.org/sparql
The result should be:
| (label) | (url)
|--------------------------|-----------------------------------
|"Kurzzeitwecker"#de | urls to the picture of the device
|"Staubsauger"#de | -||-
|"Waschmaschine"#de | -||-
|"Geschirrspülmaschine"#de | -||-
Does anyone have some tips please?
UPDATE: new query:
PREFIX cat: <http://dbpedia.org/resource/Category:>
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#>
SELECT ?s ?label WHERE {
?s ?p cat:Home_automation .
?s rdf:type owl:Thing .
?s rdfs:label ?label
FILTER (LANG(?label)='de')
}
order by ?p
It is not clear what you want. You must first know what exact related information dbpedia contains and how they are structured.
However, you can try discovering what types of relationships cat:Home_automation is involved in, thus, you may know better what you want.
I suggest starting by generic queries, to specify how cat:Home_automation occurs in dbpedia, then, you might be able to go more specific, and pose further queries.
A query to list triples where cat:Home_automation is an subject:
PREFIX cat: <http://dbpedia.org/resource/Category:>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
SELECT ?p ?o WHERE {
cat:Home_automation ?p ?o
}
order by ?p
A query to list triples where cat:Home_automation is an object:
PREFIX cat: <http://dbpedia.org/resource/Category:>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
SELECT ?s ?p WHERE {
?s ?p cat:Home_automation
}
order by ?p
check the results, see what is interesting for you, and then continue with further queries.
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.
I need to get all awarded movies on 80th Award Ceremony
I tried to write SPARQL query:
prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>
prefix dbpedia-owl: <http://dbpedia.org/ontology/>
prefix movie: <http://data.linkedmdb.org/resource/movie/>
prefix award: <http://data.linkedmdb.org/page/film_awards_ceremony/180/>
select distinct ?film ?award where {
{ ?film a movie:film.
?award a movie:film_awards_ceremony.
} union
{ ?film a dbpedia-owl:Film }
?film rdfs:label ?label .
}
But the result is full movies list.
I found the data I need also here: https://www.freebase.com/m/02pgky2
How to combine (union) these entities in a right way ?
If is not possible - How to get the result from freebase using SPARQL and dbpedia.org?
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