I want to get the information the title of a book with the most authors.
I have used the following query, however I get blank back. If I take them out individually, for example only using title info I will get some type of data, but having the two together I don't.
PREFIX dct: <http://purl.org/dc/terms/>
PREFIX dc: <http://purl.org/dc/elements/1.1/>
SELECT ?creators ?title (count(?book) as ?count)
WHERE
{ ?creators dct:creator ?book .
?title dc:title ?book .
}
group by ?creators ?title order by desc(?count)
Related
How to List the laureate awards (given by their label) for which the description of the contribution (given by nobel:motivation) contains the word "human" together with the word "peace" (i.e., both words must be there).
I have use the bds:search namespace from the the full-text search feature of Blazegraph.
After visiting this link i have composed this query
Free text search in sparql when you have multiword and scaping character
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX bds: <http://www.bigdata.com/rdf/search#>
PREFIX nobel: <http://data.nobelprize.org/terms/>
SELECT ?awards ?description
WHERE {
?entity rdfs:label ?awards .
?entity nobel:motivation ?description .
FILTER ( bds:search ( ?description, '"human" AND "peace"' ) )
}
This query is returning me the following error on execution shown in image.
Error Image
How to correct this query and get the desired result?
You may take a look at the specification of this dataset or download an RDF dump of the dataset
Use bds:search to search for "human" category.Then apply filter and contain function to "peace".
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX bds: <http://www.bigdata.com/rdf/search#>
PREFIX nobel: <http://data.nobelprize.org/terms/>
PREFIX bif: <http://www.openlinksw.com/schemas/bif#>
SELECT ?awards ?description
WHERE {
?entity rdfs:label ?awards .
?entity nobel:motivation ?description .
?description bds:search "human" .
FILTER (CONTAINS(?description, "peace"))
}
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.
The following snippet retrieves all artists (names) from around the world using the dbpedia.org database.
prefix dbo: <http://dbpedia.org/ontology/>
select distinct (str(?name_) as ?name) {
?artist a dbo:Artist ;
rdfs:label ?name_ .
}
What I would like to do next, is extend this snippet so that a) I filter by a certain city and b) present the following optional fields:
name (this works already)
city name
birth date
sub class (e.g. Actor, MusicalArtist etc.)
dbo:birthDate will give you the birth date of the artist.
dbo:birthPlace will give you the birth place of the artist.
rdf:type / dbc:subject will give you all the roles that the artist have. Be careful, this one can be tremendous. Perhaps should you refine your research (Yago, dbc, dbo, wikidata, ...).
Here is an example of artists born in Pinner and their birthDate :
prefix dbo: <http://dbpedia.org/ontology/>
select distinct (str(?name_) as ?name) ?birthPlace ?birthDate {
?artist a dbo:Artist ;
rdfs:label ?name_ .
?artist dbo:birthPlace ?birthPlace .
?artist dbo:birthDate ?birthDate .
filter(?birthPlace = dbr:Pinner)
}
I am working from this example, and I want to archieve the same, however with a different topic - Climate change
All i need to output is the abstract from this page: http://dbpedia.org/page/Climate_change
PREFIX dbp-res: <http://dbpedia.org/resource/>
PREFIX dbp-ont: <http://dbpedia.org/ontology/>
PREFIX dbp-prop: <http://dbpedia.org/property/>
SELECT *
WHERE
{
?Resource a dbp-ont:Agent .
?Resource dbp-ont:abstract ?Description .
?Resource rdfs:label ?Label .
FILTER( STR(?Label) = 'Climate_change' )
FILTER (langMatches(lang(?Description),'en'))
FILTER (langMatches(lang(?Label),'en'))
}
The problem seems to be the Agent, but I have no clue, as to what to replace it with.
My query
I'm trying to use a SPARQL query to retrieve information about a DBpedia resource (a Person). I'd like to use the same query to retrieve data about any Person by parameterizing the resource URI. Since some attributes may not exist for a particular resource, I'm making use of the OPTIONAL statement. Here is my query:
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbpprop: <http://dbpedia.org/property/>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
SELECT DISTINCT ?label ?abstract ?placeOfBirth
?birthPlace ?birthDate ?deathDate ?page ?thumbnail
WHERE {
<http://dbpedia.org/resource/Neil_Simon> rdfs:label ?label ;
dbo:abstract ?abstract ;
foaf:page ?page .
OPTIONAL {
<http://dbpedia.org/resource/Neil_Simon> dbpprop:placeOfBirth ?placeOfBirth ;
dbpprop:birthPlace ?birthPlace ;
dbo:birthDate ?birthDate ;
dbo:deathdate ?deathDate ;
dbo:thumbnail ?thumbnail .
}
FILTER (LANG(?label) = 'en')
FILTER (LANG(?abstract) = 'en')
}
LIMIT 1
I've left everything except label, abstract and page in OPTIONAL, since if I use the same query for another person, they may not have those properties. The problem is, none of those optional attributes are showing up in the results. In Neil Simon's case, you can see that there are values for birthDate, birthPlace and thumbnail: http://dbpedia.org/resource/Neil_Simon. However, those values don't show up when I run the query: DBpedia SPARQL query. What am I doing wrong, and how can I optionally retrieve those properties?
Although you have used an OPTIONAL construct the map pattern itself needs all the attributes within to match. So only if you have birthPlace, birthDate, deathDate and thumbnail the inner optional construct is satisfied
I would suggest breaking the OPTIONAL construct up into multiple OPTIONAL constructs.