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    <p>Actually, when I run the query you provided:</p> <pre><code>select COUNT(?place) where { ?place a dbpedia-owl:Place . { ?x rdfs:label "John"@en } } </code></pre> <p>I get the result 93027312, not 81900104, but that does not really matter much. The strange results arise because <code>?x</code> and <code>?place</code> don't have to be bound to the same thing, so you are getting all the <code>dbpedia-owl:Places</code> and counting them, but the number of result rows is the number of <code>dbpedia-owl:Place</code> <em>multiplied</em> by the number of things with <code>rdfs:label "John@en"</code>:</p> <pre><code>select COUNT(?place) where { ?place a dbpedia-owl:Place } =&gt; 646023 select COUNT(?x) where { ?x rdfs:label "John"@en } =&gt; 144 646023 × 144 = 93027312 </code></pre> <p>If you actually ask for <code>dbpedia-owl:Place</code>s that have the <code>rdfs:label "John@en"</code>, you'll get no results:</p> <pre><code>select COUNT(?place) as ?numPlaces where { ?place a dbpedia-owl:Place ; rdfs:label "John"@en . } </code></pre> <p><a href="http://dbpedia.org/sparql?default-graph-uri=http%3A%2F%2Fdbpedia.org&amp;query=select+COUNT%28%3Fplace%29+as+%3FnumPlaces+where+%7B%0D%0A+++%3Fplace+a+dbpedia-owl%3APlace+%3B%0D%0A++++++++++rdfs%3Alabel+%22John%22%40en+.%0D%0A%7D&amp;format=text%2Fhtml&amp;timeout=0&amp;debug=on" rel="nofollow">SPARQL results</a></p> <p>Also, you might consider using <code>dbpprop:name</code> instead of <code>rdfs:label</code>. Some results seem like they are more useful that way. For instance, let us find places called <code>"Springfield"</code>. If we ask for places with that name we get no results:</p> <pre><code>select * where { ?place a dbpedia-owl:Place ; rdfs:label "Springfield"@en . } </code></pre> <p><a href="http://dbpedia.org/sparql?default-graph-uri=http%3A%2F%2Fdbpedia.org&amp;query=select+%2a+where+%7B%0D%0A+++%3Fplace+a+dbpedia-owl%3APlace+%3B%0D%0A++++++++++rdfs%3Alabel+%22Springfield%22%40en+.%0D%0A%7D&amp;format=text%2Fhtml&amp;timeout=0&amp;debug=on" rel="nofollow">SPARQL results</a></p> <p>However, if we modify the query and use <code>dbpprop:name</code>, we get 17. Some of these are duplicates though, so you might have to do something else to remove duplicates. The point, though, is that <code>dbpprop:name</code> got some results, and <code>rdfs:label</code> didn't. </p> <pre><code>select * where { ?place a dbpedia-owl:Place ; dbpprop:name "Springfield"@en . } </code></pre> <p><a href="http://dbpedia.org/sparql?default-graph-uri=http%3A%2F%2Fdbpedia.org&amp;query=select+%2a+where+%7B%0D%0A+++%3Fplace+a+dbpedia-owl%3APlace+%3B%0D%0A++++++++++dbpprop%3Aname+%22Springfield%22%40en+.%0D%0A%7D&amp;format=text%2Fhtml&amp;timeout=0&amp;debug=on" rel="nofollow">SPARQL results</a></p> <p>You can even use <code>dbpprop:name</code> in working with the names of persons, although it's not as useful, because the <code>dbpprop:name</code> value for most persons is their entire name. To find persons with the given name John using <code>dbpprop:name</code> requires a query like:</p> <pre><code>select * where { ?place a dbpedia-owl:Person ; dbpprop:name ?name . FILTER( STRSTARTS( str( ?name ), "John" ) ) } </code></pre> <p>(or you could use CONTAINS instead of STRSTARTS), but this becomes <em>much</em> more expensive, because it has to select all persons and their names, and then filter through that set. Being able to select persons based on a specific name (e.g., with <code>foaf:givenName</code>) is much more efficient.</p>
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    1. POHow to know if a string is a proper name of person or a place name using DBpedia?
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    1. POHow to know if a string is a proper name of person or a place name using DBpedia?
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    1. COTnx for your clear explaination, now I will document better about SPARQL. I have understand my error but I have some problem with the query that count the number of instance of a place, this one: select COUNT(?place) as ?numPlaces where { ?place a dbpedia-owl:Place ; rdfs:label "Roma"@en . } As you can see if I put "Roma" as parameter the output is: numPlaces=0 If I change it and I use "Rome" the output is numPlaces=1 Why this behavior?
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      1. USAndreaNobili
    2. CO@AndreaNobili The `@en` is a language tag for the literal. The English name is "Rome", not "Roma". If you use the query `SELECT * WHERE { ?place a dbpedia-owl:Place ; rdfs:label "Roma"@it }`, you'll see one row in [the results](http://dbpedia.org/sparql?default-graph-uri=http%3A%2F%2Fdbpedia.org&query=SELECT+*+WHERE+%7B+%3Fplace+a+dbpedia-owl%3APlace+%3B+rdfs%3Alabel+%22Roma%22%40it+%7D&format=text%2Fhtml&timeout=0&debug=on).
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    3. CO@AndreaNobili As mentioned in [this answer](http://stackoverflow.com/a/2015371/1281433), you can do search for strings while ignoring their language tags, but this requires a FILTER and string comparison, and is much slower. If you're searching for strings in Italian (English), it's best to use `@it` (`@en`).
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