Question

我（几乎）遇到与here相同的问题。但我无法弄清楚如何将它应用于我的问题。我想将SPARQL查询转换为其algebra expression。所以示例代码：

Query query = QueryFactory.create(args[0]);
Op op = Algebra.compile(query) ;
System.out.println(op);

然而，as Joshua said：Virtuoso接受非标准SPARQL而Jena不接受..错误是：

Exception in thread "main" org.apache.jena.query.QueryParseException: Encountered " "<" "< "" at line 1, column 14.

手动更正查询并不是真正的解决方案，因为我想通过几百个查询来执行此操作...感谢您的帮助

修改

示例查询：

PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 
SELECT * 
WHERE 
  { 
    {?city rdfs:label 'Tapiramutá'@en.} 
  UNION 
    { ?alias <http://dbpedia.org/property/redirect> ?city;
      rdfs:label 'Tapiramutá'@en. } 
  UNION 
    {?alias <http://dbpedia.org/property/disambiguates> ?city;
     rdfs:label 'Tapiramutá'@en. } 
OPTIONAL { ?city <http://dbpedia.org/ontology/abstract> ?abstract}
OPTIONAL { ?city geo:lat ?latitude; geo:long ?longitude}
OPTIONAL { ?city foaf:depiction ?image } 
OPTIONAL { ?city rdfs:label ?name } 
OPTIONAL { ?city foaf:homepage ?home } 
OPTIONAL { ?city <http://dbpedia.org/ontology/populationTotal> ?population } 
OPTIONAL { ?city <http://dbpedia.org/ontology/thumbnail> ?thumbnail } FILTER (langMatches( lang(?abstract), 'en'))}

Jena Algebra.compile（）非标准SPARQL查询

0 个答案: