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copied!<p>Forget it. You won't be able to get that query back from dbpedia with just one SPARQL. Those optionals are very expensive.</p> <p>To work it around you need to first run something like:</p> <pre><code> SELECT DISTINCT ?uri WHERE { ?uri rdf:type dbpedia-owl:EducationalInstitution . ?uri foaf:name ?name . } ORDER BY ?uri LIMIT 20 OFFSET 10 </code></pre> <p>Then iterate over the resultset of this query to form single queries for each <code>dbpedia-owl:EducationalInstitution</code> such as ... (notice the filter at the end of the query):</p> <pre><code> SELECT DISTINCT ?uri ?name ?homepage ?student_count ?native_name ?city ?country ?type ?lat ?long ?image WHERE { ?uri rdf:type dbpedia-owl:EducationalInstitution . ?uri foaf:name ?name . OPTIONAL { ?uri foaf:homepage ?homepage } . OPTIONAL { ?uri dbpedia-owl:numberOfStudents ?student_count } . OPTIONAL { ?uri dbpprop:nativeName ?native_name } . OPTIONAL { ?uri dbpprop:city ?city } . OPTIONAL { ?uri dbpprop:country ?country } . OPTIONAL { ?uri dbpprop:type ?type } . OPTIONAL { ?uri geo:lat ?lat . ?uri geo:long ?long } . OPTIONAL { ?uri foaf:depiction ?image } . FILTER (?uri = <http://dbpedia.org/resource/%C3%89cole_%C3%A9l%C3%A9mentaire_Marie-Curie>) } </code></pre> <p>Where <code><http://dbpedia.org/resource/%C3%89cole_%C3%A9l%C3%A9mentaire_Marie-Curie></code> has been obtained from the first query.</p> <p>... and yes it will be slow and you might not be able to run this for an online application. Advice: try to work out some sort of caching mechanism to sit between your app and the dbpedia SPARQL endpoint. </p>

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