# AGSparqlDistinct.java

`package com.franz.agbase.examples;
import com.franz.agbase.*;
public class AGSparqlDistinct {
/**
* Demonstrates some basics of using DISTINCT in SPARQL
*
* @param args unused
* @throws AllegroGraphException
*/
public static void main(String[] args) throws AllegroGraphException {
// Connect to server, which must already be running.
AllegroGraphConnection ags = new AllegroGraphConnection();
try {
ags.enable();
} catch (Exception e) {
throw new AllegroGraphException("Server connection problem", e);
}
// Create fresh triple-store for this example.
AllegroGraph ts = ags.renew("sparql", AGPaths.TRIPLE_STORES);
// Register any namespaces
ts.registerNamespace("foaf", "http://xmlns.com/foaf/0.1/");
// Define blank nodes
BlankNode x = (BlankNode)ts.createBNode("_:x");
BlankNode y = (BlankNode)ts.createBNode("_:y");
BlankNode z = (BlankNode)ts.createBNode("_:z");
// Add some data to the store
ts.addStatement(x,"!foaf:name",ts.createLiteral("Alice"));
ts.addStatement(x,"!foaf:mbox","<mailto:alice@example.com>");
ts.addStatement(y,"!foaf:name",ts.createLiteral("Alice"));
ts.addStatement(y,"!foaf:mbox","<mailto:asmith@example.com>");
ts.addStatement(z,"!foaf:name",ts.createLiteral("Alice"));
ts.addStatement(z,"!foaf:mbox","<mailto:alice.smith@example.com>");
// Query first without using the DISTINCT solution modifier.
// Note that duplicate solutions are preserved.
String query =
"PREFIX foaf: <http://xmlns.com/foaf/0.1/> " +
"SELECT ?name WHERE { ?x foaf:name ?name } ";
// Query the store and show the results
SPARQLQuery sq = new SPARQLQuery();
sq.setTripleStore(ts);
sq.setQuery(query);
AGSparqlSelect.doSparqlSelect(sq);
// Now query using DISTINCT
query =
"PREFIX foaf: <http://xmlns.com/foaf/0.1/> " +
"SELECT DISTINCT ?name WHERE { ?x foaf:name ?name } ";
// Query the store and show the results
sq.setQuery(query);
AGSparqlSelect.doSparqlSelect(sq);
// Close the triple store and disconnect from the server.
ts.closeTripleStore();
ags.disable();
}
}
`

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