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从dbpedia检索数据时出错

[英]Error with retrieving data from dbpedia

Hey guys I've got a problem with my sparql query can anyone help me. 嗨,我的sparql查询有问题,谁能帮助我。

String queryString = 
 "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>"+
 "PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>"+
 "PREFIX type: <http://dbpedia.org/class/yago/>"+
 "PREFIX dbpedia-owl: <http://dbpedia.org/ontology/>"+
 "PREFIX prop: <http://dbpedia.org/property/>"+
 "PREFIX foaf:  <http://xmlns.com/foaf/0.1/>"+
 "SELECT "+ 
 "?description "+
 "FROM <http://dbpedia.org/page/Arctic_Monkeys> "+
"WHERE " +
"{"+
"?x foaf:depiction ?description."+
"}";

Query query = QueryFactory.create(queryString);
    //initializing queryExecution factory with remote service.
    QueryExecution qexec=QueryExecutionFactory.sparqlService("http://dbpedia.org/sparql", query);
    //query execution and result processing
    try {
        //simple select
        ResultSet results = qexec.execSelect();
        ResultSetFormatter.out(System.out, results, query);
    }
    finally{
        qexec.close();
    }
}

It doesn't retrieve the data needed from dbpedia. 它不会从dbpedia检索所需的数据。 I want to retrieve the data from one specific dbpedia page 我想从一个特定的dbpedia页面检索数据

You've got the wrong IRI for identifying the page. 您识别该页面的IRI错误。 It's not page , but resource . 不是page ,而是resource Additionally, it's a resource in the graph, not (as far as I know) a named, graph, so you don't need the FROM in your query. 此外,它是图形中的一种资源,而不是(据我所知)一个命名图形,因此您在查询中不需要FROM Here's a query that works: 这是一个有效的查询:

PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX type: <http://dbpedia.org/class/yago/>
PREFIX dbpedia-owl: <http://dbpedia.org/ontology/>
PREFIX prop: <http://dbpedia.org/property/>
PREFIX foaf:  <http://xmlns.com/foaf/0.1/>
SELECT ?depiction
WHERE {
  <http://dbpedia.org/resource/Arctic_Monkeys> foaf:depiction ?depiction
}

The results have one row, a photo of the Arctic Monkeys playing at MSG. 结果有一行,一张在MSG上玩的北极猴子的照片。

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