SPARQL Endpoint に AJAX でアクセスする方法 ref: http://qiita.com/frogcat/items/beb8888bb334699e21ed

endpoint

http://ja.dbpedia.org/sparql

query-via-get

<script>
  var endpoint = "http://ja.dbpedia.org/sparql";
  var query = "select (count(*) as ?count) where {?s ?p ?o.}";

  var x = new XMLHttpRequest();
  x.onreadystatechange = function() {
    if (x.readyState == 4 && x.status == 200)
      document.body.appendChild(document.createTextNode(x.responseText));
  };
  x.open("GET", endpoint + "?query=" + encodeURIComponent(query), true);
  x.setRequestHeader("Accept", "application/sparql-results+json");
  x.send();
</script>

query-via-post-directly

<script>
  var endpoint = "http://ja.dbpedia.org/sparql";
  var query = "select (count(*) as ?count) where {?s ?p ?o.}";

  var x = new XMLHttpRequest();
  x.onreadystatechange = function() {
    if (x.readyState == 4 && x.status == 200)
      document.body.appendChild(document.createTextNode(x.responseText));
  };
  x.open("POST", endpoint, true);
  x.setRequestHeader("Accept", "application/sparql-results+json");
  x.setRequestHeader("Content-Type", "application/sparql-query");
  x.send(query);
</script>

query-via-url-encoded-post

<script>
  var endpoint = "http://ja.dbpedia.org/sparql";
  var query = "select (count(*) as ?count) where {?s ?p ?o.}";

  var x = new XMLHttpRequest();
  x.onreadystatechange = function() {
    if (x.readyState == 4 && x.status == 200)
      document.body.appendChild(document.createTextNode(x.responseText));
  };
  x.open("POST", endpoint, true);
  x.setRequestHeader("Accept", "application/sparql-results+json");
  x.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
  x.send("query=" + encodeURIComponent(query));
</script>

sparql

select (count(*) as ?count) where {?s ?p ?o.}