生成增量SPARQL查询

Question

有什么方法可以动态生成SPARQL查询吗？ 我想做的是这样的：如果我有一个DBpedia资源r1和另一个DBpedia资源r2，则此查询

SELECT * WHERE { <r1> ?pre <r2> }

将返回2个资源与该查询之间的谓词

SELECT * WHERE { <r1> ?pre1 ?obj1 . ?obj1 ?pre2 <r2> }

会在两个步骤中返回这两个资源之间的所有谓词和对象，依此类推，我试图以这种方式构建此查询，该查询将自动增加两个资源之间的对象和谓词的数量（例如4个步骤）？

Answer 1

我想出了解决这个问题的方法..这是我的解决方案：

private String completeQuery(String coreQuery){
String completeQuery = "";
completeQuery += "SELECT * WHERE {"+ "\n";
completeQuery += coreQuery + "\n";
completeQuery =completeQuery + "}" + "\n" +"limit 5" ;
return completeQuery;}
public String link(String object1, String object2, int distance){
if(distance == 1){
    String Quer = "<http://dbpedia.org/resource/"+object1+">" + " ?pre1 " +"<http://dbpedia.org/resource/"+object2+">";
    return completeQuery(Quer);
} 
else {
    String query = "<http://dbpedia.org/resource/"+object1+">" + " ?pre1 ?obj1 " + ".\n";
    for(int i = 1; i < distance-1; i++){
        query += "?obj" + i + " ?pre" + (i+1) + " ?obj" + (i+1) + ".\n" ;

    }
    query  += "?obj" + (distance-1) + " ?pre" + distance + " " + "<http://dbpedia.org/resource/"+object2+">";
    return completeQuery(query);
}}