You’re right that your query isn’t returning all the companies. The pattern is correct, though. Notice that this query which only counts the companies returns 88054: prefix dbpedia-owl: <http://dbpedia.org/ontology/> select (count(distinct ?company) as ?count) where { ?company a dbpedia-owl:Company } SPARQL results I think this is a limit imposed by the DBpedia SPARQL endpoint for … Read more
You can use Jena’s ARQ to execute queries against remote SPARQL endpoints. The process is described in ARQ — Querying Remote SPARQL Services. Using ParameterizedSparqlStrings in SELECT queries To do this for different places that you might not know until it is time to execute the query, you can use a ParameterizedSparqlString to hold the query and … Read more
Your direction was wrong. select distinct * where { ?x dbpedia-owl:wikiPageRedirects <http://dbpedia.org/resource/Paris> }
It might seem a little awkward, but your comment about casting to a string and doing some string-based checks is probably on the right track. You can do it a little bit more efficiently using the SPARQL 1.1 function strstarts: SELECT DISTINCT ?concept WHERE { ?x a ?concept FILTER ( !strstarts(str(?concept), “http://dbpedia.org/class/yago/”) ) } LIMIT … Read more
that is so embarassing, there is space problem in the query: String service = “http://dbpedia.org/sparql”; String queryString = “”; queryString = “PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> SELECT ?label ” + “WHERE {” + “<http://dbpedia.org/resource/Quatre_Bornes> <http://dbpedia.org/ontology/country> ?y .”+ “?y rdfs:label ?label .”+ “FILTER (LANG(?label) = ‘en’)”+ “}”;
The wrong way: trying to parse HTML Use (cURL/jQuery/file_get_contents/requests/wget/more jQuery) to fetch the HTML article code of the article, then use a DOM parser to extract table.infobox tr[3] td / use a regex. This is actually a really bad idea most of the time. Wikipedia’s HTML code is not particularly parsing-friendly (especially infoboxes which are … Read more