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Share, discover and reuse the Linked Data has never been easier with a LinkedWiki Platform.

Using SPARQL 1.1 Property Paths to explore DBpedia Class Hierarchy, transitively
Demonstrating transitivity via a SPARQL 1.1 Property Path Query via the massive 30 Billion+ Live LOD Cloud Cache instance.

Reuse these data in your code

Query, endpoint and code for reusing the same data
http://lod.openlinksw.com/sparql
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 
PREFIX owl: <http://www.w3.org/2002/07/owl#> 

SELECT ?superclass ?subclass
FROM <http://dbpedia.org> 
WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass } 

LIMIT 100
Howto write a query SPARQL? (in french)
{{#sparql:PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 
PREFIX owl: <http://www.w3.org/2002/07/owl#> 

SELECT ?superclass ?subclass
FROM <http://dbpedia.org> 
WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass } 

LIMIT 100            
| endpoint = http://lod.openlinksw.com/sparql }}
Howto insert this graph in my wiki ?
Test this script in a new tab.
<html>
    <head>
        <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script>
    </head>
    <body onload="testQuery();">
        <script>
function testQuery(){
    var endpoint = "http://lod.openlinksw.com/sparql";
    var query = "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n\
PREFIX owl: <http://www.w3.org/2002/07/owl#>\n\
SELECT ?superclass ?subclass\n\
FROM <http://dbpedia.org>\n\
WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass }\n\
LIMIT 100"

   // $('#bodyContentResearch').append(queryDataset);
    $.ajax({
                url: endpoint,
                dataType: 'json', 
                data: { 
                    queryLn: 'SPARQL',
                    query: query , 
                    limit: 'none',
                    infer: 'true',
                    Accept: 'application/sparql-results+json'
                },
                success: displayResult, 
                error: displayError
        });
}

function displayError(xhr, textStatus, errorThrown) {
    console.log(textStatus);
    console.log(errorThrown);
}

function displayResult(data) {
    $.each(data.results.bindings, function(index, bs) {
        console.log(bs);
        $("body").append(JSON.stringify(bs) + "<hr/>");
    });
}

        </script>
    </body>    
</html>
</pre>
  
Test this script in a new tab.
Howto insert this graph in my html page?
<html>
    <head>
        <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script>
        <script type="text/javascript" src="https://www.google.com/jsapi"></script>
        <script type="text/javascript" src="js/sgvizler/sgvizler.js"></script>
    </head>
<body style="margin:0;">
<div id="sgvzl_example_query" 
   data-sgvizler-endpoint="http://lod.openlinksw.com/sparql" 
   data-sgvizler-query="PREFIX rdfs: &lt;http://www.w3.org/2000/01/rdf-schema#&gt; 
PREFIX owl: &lt;http://www.w3.org/2002/07/owl#&gt; 

SELECT ?superclass ?subclass
FROM &lt;http://dbpedia.org&gt; 
WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass } 

LIMIT 100" 
    data-sgvizler-chart='google.visualization.Table'             
    data-sgvizler-chart-options=''  
    data-sgvizler-endpoint_output_format='json'
    data-sgvizler-loglevel='2'   
    style='width:100%; height:450px;'  />



<script>
$(document).ready(function() { 
    sgvizler.containerDrawAll();   
    
});
</script>

</body>
</html>
from SPARQLWrapper import SPARQLWrapper, JSON

sparql = SPARQLWrapper("http://lod.openlinksw.com/sparql")
sparql.setQuery("""
    PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 
PREFIX owl: <http://www.w3.org/2002/07/owl#> 

SELECT ?superclass ?subclass
FROM <http://dbpedia.org> 
WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass } 

LIMIT 100""")
sparql.setReturnFormat(JSON)
results = sparql.query().convert()

for result in results["results"]["bindings"]:
    print(result)
    #print(result["label"]["value"])
Howto use SPARQL with Python ?
library(SPARQL) # SPARQL querying package
library(ggplot2)
 
# Step 1 - Set up preliminaries and define query
# Define the data.gov endpoint
endpoint <- "http://lod.openlinksw.com/sparql"
# create query statement
query <- "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 
PREFIX owl: <http://www.w3.org/2002/07/owl#> 

SELECT ?superclass ?subclass
FROM <http://dbpedia.org> 
WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass } 

LIMIT 100" 
# Step 2 - Use SPARQL package to submit query and save results to a data frame
qd <- SPARQL(endpoint,query)
df <- qd$results
SPARQL with R in less than 5 minutes
#!/usr/bin/env ruby
#
# Install sparql for Ruby
#   gem update --system
#   gem install sparql
#
require 'sparql/client'

endpoint = "http://lod.openlinksw.com/sparql"
sparql = <<-EOT
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 
PREFIX owl: <http://www.w3.org/2002/07/owl#> 

SELECT ?superclass ?subclass
FROM <http://dbpedia.org> 
WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass } 

LIMIT 100
EOT

#For Wikidata, the method get is required
#For other SPARQL endpoints, the method post is prefered
client = SPARQL::Client.new(endpoint, :method => :get)
rows = client.query(sparql)

puts "Number of rows: #{rows.size}"
for row in rows
  for key,val in row do
    # print "#{key.to_s.ljust(10)}: #{val}\t"
    print "#{key}: #{val}\t"
  end
  print "\n"
end
Doc Ruby for SPARQL 1.1
endpoint = 'http://lod.openlinksw.com/sparql';

query = ['PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>  '...
'PREFIX owl: <http://www.w3.org/2002/07/owl#>  '...
' '...
'SELECT ?superclass ?subclass '...
'FROM <http://dbpedia.org>  '...
'WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass }  '...
' '...
'LIMIT 100 '];

url_head = strcat(endpoint,'?query=');
url_query = urlencode(query);
format = 'text/tab-separated-values';
url_tail = strcat('&format=', format);

url = strcat(url_head, url_query, url_tail);

% get the data from the endpoint
query_results = urlread(url);

% write the data to a file so that tdfread can parse it
fid = fopen('query_results.txt','w');
if fid>=0
    fprintf(fid, '%s\n', query_results)
    fclose(fid)
end

% this reads the tsv file into a struct
sparql_data = tdfread('query_results.txt')
Project Github MatlabSPARQL
<?php 
require_once('lib/SPARQL/Endpoint.php');

$endpoint ="http://lod.openlinksw.com/sparql";
$sp_readonly = new Endpoint($endpoint);
$q = <<<EOD
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 
PREFIX owl: <http://www.w3.org/2002/07/owl#> 

SELECT ?superclass ?subclass
FROM <http://dbpedia.org> 
WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass } 

LIMIT 100EOD;
$rows = $sp_readonly->query($q, 'rows');
$err = $sp_readonly->getErrors();
if ($err) {
      print_r($err);
      throw new Exception(print_r($err,true));
}

foreach($rows["result"]["variables"] as $variable){
        printf("%-20.20s",$variable);
        echo '|';
 }
 echo "\n";

foreach ($rows["result"]["rows"] as $row){
        foreach($rows["result"]["variables"] as $variable){
                printf("%-20.20s",$row[$variable]);
        echo '|';
        }
        echo "\n";
 }
 ?>
Project Github BorderCloud/SPARQL
import com.bordercloud.sparql.Endpoint;
import java.util.ArrayList;
import java.util.HashMap;

public class Main {

    public static void main(String[] args) {
        try {
            Endpoint sp = new Endpoint("http://lod.openlinksw.com/sparql";, false);

            String querySelect = 'PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>  \n'
                    + 'PREFIX owl: <http://www.w3.org/2002/07/owl#>  \n'
                    + ' \n'
                    + 'SELECT ?superclass ?subclass \n'
                    + 'FROM <http://dbpedia.org>  \n'
                    + 'WHERE {?superclass a owl:Class ; rdfs:subClassOf+ ?subclass }  \n'
                    + ' \n'
                    + 'LIMIT 100 \n';

            HashMap rs = sp.query(querySelect);
            printResult(rs,30);

        }catch(EndpointException eex) {
            System.out.println(eex);
            eex.printStackTrace();
        }
    }

    public static void printResult(HashMap rs , int size) {

      for (String variable : (ArrayList) rs.get("result").get("variables")) {
        System.out.print(String.format("%-"+size+"."+size+"s", variable ) + " | ");
      }
      System.out.print("\n");
      for (HashMap value : (ArrayList>) rs.get("result").get("rows")) {
        //System.out.print(value);
        /* for (String key : value.keySet()) {
         System.out.println(value.get(key));
         }*/
        for (String variable : (ArrayList) rs.get("result").get("variables")) {
          //System.out.println(value.get(variable));
          System.out.print(String.format("%-"+size+"."+size+"s", value.get(variable)) + " | ");
        }
        System.out.print("\n");
      }
    }
}
Project Github BorderCloud/SPARQL-JAVA