I created this query to return all books that are notable works by George Orwell but it returns no result.
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbp: <http://dbpedia.org/resource/>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
SELECT ?name ?title where {
?person foaf:name ?name .
?title dbo:author ?person .
?title dbo:notableWork dbp:George_Orwell .
}
I cannot seem to figure out why there is no result.
I am running the query in http://dbpedia.org/snorql
Don't you have the triples about notable works in the wrong order?
Try rewriting based on this working query
SELECT *
WHERE {
:George_Orwell dbo:notableWork ?title
}
.
title
:Nineteen_Eighty-Four
:Animal_Farm
You can also bind :George_Orwell to a variable and ask more about that:
SELECT *
WHERE {
values ?author { :George_Orwell } .
?author rdfs:label ?l .
?title ?p ?author .
?title rdf:type dbo:Book .
filter (lang(?l) = "en")
}
and DESCRIBE things
describe :Animal_Farm
Related
Why can get results with this query:
SELECT *
WHERE {
?person rdfs:label "Kirk Douglas"#en;
dbo:birthPlace ?place. # With dbp: too
}
but not with another one:
SELECT *
WHERE {
?person rdfs:label "Kirk Douglas"#en;
dbo:starring ?film.
}
I'm following tags in https://dbpedia.org/page/Kirk_Douglas
Some tip to understand it.
Thx!
In dbr:Kirk_Douglas you can read:
dbo:birthPlace dbr:Amsterdam_(city),_New_York
...
is dbo:starring of dbr:The_Light_at_the_Edge_of_the_World
dbr:Cast_a_Giant_Shadow
dbr:Two-Fisted_Tales_(film)
...
where is dbo:starring of is a way of simulating an inverse property for dbo:starring.
Indeed, in dbo:starring you can read:
rdfs:domain dbo:Work
...
rdfs:range dbo:Actor
This means that you shouldn't build triples like ?actor dbo:starring ?work, while ?work dbo:starring ?actor is a valid triple.
So your query should be something like:
SELECT *
WHERE {
?person rdfs:label "Kirk Douglas"#en .
?film dbo:starring ?person .
}
I am struggling a lot to create some SPARQL queries. I need 3 specific things, and this is what i have so far:
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/>
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbp: <http://dbpedia.org/property/>
select distinct ?title ?author ?country ?genre ?language
where {
?s rdf:type dbo:Book;
dbp:title ?title;
dbp:author ?author;
dbp:country ?country;
dbp:genre ?genre;
dbp:language ?language.
}
This query will bring me a list of all books. What i really need is the ability to add some filters to this code. There are 3 things i want to filter by:
specific title name (e.g., search for title with "harry potter")
specific author name (e.g., search for author with "J. K. Rowling")
specific genre (e.g., search for genre with "adventure")
I've been struggling with this for too long and i simply cannot define these 3 queries. I am trying to implement a function that will execute a SPARQL statement using parameters passed by an user form. I found a few examples here and in the web but i just cannot build these 3 specific queries.
As noted, not every book has every property, and some of your properties may not exist at all. For instance, I changed dbp:genre to dbo:literaryGenre, based on the description of Harry Potter and the Goblet of Fire. See query form, and results.
SELECT *
WHERE
{ ?s rdf:type dbo:Book .
?s rdfs:label ?bookLabel .
FILTER(LANGMATCHES(LANG(?bookLabel), 'en'))
?s dbo:author ?author .
?author rdfs:label ?authorLabel .
FILTER(LANGMATCHES(LANG(?authorLabel), 'en'))
?authorLabel bif:contains "Rowling"
OPTIONAL { ?s dbp:country ?country .
?country rdfs:label ?countryLabel .
FILTER(LANGMATCHES(LANG(?countryLabel), 'en')) }
OPTIONAL { ?s dbo:literaryGenre ?genre .
?genre rdfs:label ?genreLabel .
FILTER(LANGMATCHES(LANG(?genreLabel), 'en')) }
OPTIONAL { ?s dbp:language ?language .
?language rdfs:label ?languageLabel .
FILTER(LANGMATCHES(LANG(?languageLabel), 'en')) }
}
I'm trying to run this Sparql statement to read data from DBpedia; However, it only return the column names and no row data.
If anybody can let me know what's the issue. I'll be more appreciated
Sparql query below:
PREFIX dbp: <http://dbpedia.org/property/>
PREFIX dc: <http://purl.org/dc/terms/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
SELECT ?actor ?movie ?director ?movie_date
WHERE {
?m dc:subject <http://dbpedia.org/resource/Category:American_films> .
?m rdfs:label ?movie .
FILTER(LANG(?movie) = "en")
?m dbp:released ?movie_date .
FILTER(DATATYPE(?movie_date) = xsd:date)
?m dbp:starring ?a .
?a rdfs:label ?actor .
FILTER(LANG(?actor) = "en")
?m dbp:director ?d .
?d rdfs:label ?director .
FILTER(LANG(?director) = "en")
}
The problem is not all the queried triples exist. If at least one of the relations doesnt exist, no result will be given.
So with the OPTIONAL keyword, answers will be given only if they exist and wont block your query if they don't. It simply leaves the missing value empty.
PREFIX dbp: <http://dbpedia.org/property/>
PREFIX dc: <http://purl.org/dc/terms/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
SELECT ?actor ?movie ?director ?movie_date
WHERE {
?m dc:subject <http://dbpedia.org/resource/Category:American_films> .
OPTIONAL{
?m rdfs:label ?movie .
FILTER(LANG(?movie) = "en") }
OPTIONAL {
?m dbp:released ?movie_date .
FILTER(DATATYPE(?movie_date) = xsd:date) }
OPTIONAL{
?m dbp:starring ?a .
?a rdfs:label ?actor .
FILTER(LANG(?actor) = "en") }
OPTIONAL{
?m dbp:director ?d .
?d rdfs:label ?director .
FILTER(LANG(?director) = "en") }
}
I created the following SPARQL query to Wikidata. And the result of this query are records related to states in Germany. But as you can see, results are occurring four times in a row (you can test it here: https://query.wikidata.org/). I supposed that there is a problem with geo coordinates and languages but I can't resolve it anyway. What is wrong with this query and how can I fix it to receive a result without repetition?
PREFIX p: <http://www.wikidata.org/prop/>
PREFIX schema: <http://schema.org/>
PREFIX psv: <http://www.wikidata.org/prop/statement/value/>
PREFIX wdt: <http://www.wikidata.org/prop/direct/>
PREFIX wikibase: <http://wikiba.se/ontology#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX wd: <http://www.wikidata.org/entity/>
SELECT DISTINCT ?subject ?featureCode ?countryCode ?name ?latitude ?longitude ?description ?iso31662
WHERE
{ ?subject wdt:P31 wd:Q1221156 ;
rdfs:label ?name ;
wdt:P17 ?countryClass .
?countryClass
wdt:P297 ?countryCode .
?subject wdt:P31/(wdt:P279)* ?adminArea .
?adminArea wdt:P2452 "A.ADM1" ;
wdt:P2452 ?featureCode .
?subject wdt:P300 ?iso31662
OPTIONAL
{ ?subject schema:description ?description
FILTER ( lang(?description) = "en" )
?subject p:P625 ?coordinate .
?coordinate psv:P625 ?coordinateNode .
?coordinateNode
wikibase:geoLatitude ?latitude ;
wikibase:geoLongitude ?longitude
}
FILTER ( lang(?name) = "en" )
FILTER EXISTS { ?subject wdt:P300 ?iso31662 }
}
ORDER BY lcase(?name)
OFFSET 0
LIMIT 200
In short, "9.0411111111111"^^xsd:double and "9.0411111111111"^^xsd:decimal are distinct, though they might be equal in some sense.
Check this:
SELECT DISTINCT ?subject ?featureCode ?countryCode ?name ?description ?iso31662
(datatype(?latitude) AS ?lat)
(datatype(?longitude) AS ?long)
and this:
SELECT DISTINCT ?subject ?featureCode ?countryCode ?name ?description ?iso31662
(xsd:decimal(?latitude) AS ?lat)
(xsd:decimal(?longitude) AS ?long)
I am trying to query dbpedia to get some people data and I don't have subjects just names of the people I want to query and their birth/death dates.
I am trying to do a query along these lines. I want the name, birth date, death date and thumbnail of everyone with the surname Presley. What I then intend to do is loop through the results returned and find the best match for Elvis Presley 1935-1977 which is the data I have.
PREFIX dbo: <http://dbpedia.org/ontology/>
SELECT ?Name ?thumbnail ?birthDate ?deathDate WHERE {
{
dbo:name ?Name ;
dbo:birthDate ?birthDate ;
dbo:birthDate ?deathDate ;
dbo:thumbnail ?thumbnail ;
FILTER contains(?Name#en, "Presley")
}
What is the best way to construct my sparql query?
UPDATE:
I have put together this query which seems to work to some extent but I don't entirely understand it, and I can't figure out the contains, but it does at least run and return results.
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX dbo: <http://dbpedia.org/ontology/>
SELECT ?subject ?thumbnail ?birthdate ?deathdate WHERE {
{
?subject rdfs:label "Elvis Presley"#en ;
dbo:thumbnail ?thumbnail ;
dbo:birthDate ?birthdate ;
dbo:deathDate ?deathdate ;
a owl:Thing .
}
UNION
{
?altName rdfs:label "Elvis Presley"#en ;
dbo:thumbnail ?thumbnail ;
dbo:birthDate ?birthdate ;
dbo:deathDate ?deathdate ;
dbo:wikiPageRedirects ?s .
}
}
Some entities might not have all of that information, so it's better to use optional. You can use foaf:surname to check for surname directly.
select * where {
?s foaf:surname "Presley"#en
optional { ?s dbo:name ?name }
optional { ?s dbo:birthDate ?birth }
optional { ?s dbo:deathDate ?death }
optional { ?s dbo:thumbnail ?thumb }
}