example of stardog sparql insert query in java

Deadly 提交于 2019-12-08 04:33:50

问题


Can somebody give one java example of sparql insert/Delete query in Stardog.

there is only queryExecution.execSelect() method available. there is no queryExecution.execInsert() or queryExecution.execDelete() available. Please give one working example.

EDIT

I've found this this from stardog docs page.

http://stardog.com/docs/#notes

As of 1.1.5, Stardog's SPARQL 1.1 support does not include: UPDATE query language

does that means no way out for editing a tuple once entered?


回答1:


Stardog does not yet support SPARQL update, but as was pointed out to you on the mailing list, there are 5 ways you can modify the data once it's loaded. You can use our HTTP protocol directly, any of the 3 Java API's we support, or you can use the command line interface.




回答2:


Below one is a sample program of inserting a graph and removing it.

package com.query;

import java.util.List;

import org.openrdf.model.Graph;
import org.openrdf.model.Statement;
import org.openrdf.model.URI;
import org.openrdf.model.impl.GraphImpl;
import org.openrdf.model.impl.ValueFactoryImpl;
import org.openrdf.query.QueryEvaluationException;

import com.clarkparsia.stardog.StardogDBMS;
import com.clarkparsia.stardog.StardogException;
import com.clarkparsia.stardog.api.Connection;
import com.clarkparsia.stardog.api.ConnectionConfiguration;
import com.clarkparsia.stardog.jena.SDJenaFactory;
import com.hp.hpl.jena.query.ParameterizedSparqlString;
import com.hp.hpl.jena.query.QueryExecution;
import com.hp.hpl.jena.query.QueryExecutionFactory;
import com.hp.hpl.jena.query.ResultSet;
import com.hp.hpl.jena.query.ResultSetFormatter;
import com.hp.hpl.jena.rdf.model.Model;

public class test {
public static void main(String[] args) throws StardogException, QueryEvaluationException {
    String appDbName ="memDb";
    String selectQuery="SELECT DISTINCT ?s ?p ?o WHERE { ?s ?p  ?o }";
    StardogDBMS dbms = StardogDBMS.toServer("snarl://localhost:5820/")
            .credentials("admin", "admin".toCharArray()).login();
    List<String> dbList = (List<String>) dbms.list();
    if (dbList.contains(appDbName)) {
        System.out.println("droping " + appDbName);
        dbms.drop(appDbName);
    }
    dbms.createMemory(appDbName);
    dbms.logout();
    Connection aConn = ConnectionConfiguration
            .to("memDb")    // the name of the db to connect to
            .credentials("admin", "admin") // credentials to use while connecting
            .url("snarl://localhost:5820/")
            .connect(); 
    Model aModel = SDJenaFactory.createModel(aConn);
    System.out.println("################ GRAPH IS EMPTY B4 SUBMITTING ="+aModel.getGraph()+ "################");

    URI order = ValueFactoryImpl.getInstance().createURI("RDF:president1");
    URI givenName = ValueFactoryImpl.getInstance().createURI("RDF:lincoln");
    URI predicate = ValueFactoryImpl.getInstance().createURI("RDF:GivenNane");


    Statement aStmt = ValueFactoryImpl.getInstance().createStatement(order,predicate,givenName);
    Graph aGraph = new GraphImpl();
    aGraph.add(aStmt);
    insert(aConn, aGraph);


    ParameterizedSparqlString paraQuery = new ParameterizedSparqlString(selectQuery);
    QueryExecution qExecution = QueryExecutionFactory.create(paraQuery.asQuery(),aModel);
    ResultSet queryResult = qExecution.execSelect();
    System.out.println("############### 1 TUPPLE CAME AFTER INSERT ################");
    ResultSetFormatter.out(System.out, queryResult);

    aGraph.add(aStmt);
    remove(aConn, aGraph);


    paraQuery = new ParameterizedSparqlString(selectQuery);
    qExecution = QueryExecutionFactory.create(paraQuery.asQuery(),aModel);
    queryResult = qExecution.execSelect();
    System.out.println("################ DB AGAIN EMPTY AFTER REMOVE ################");
    ResultSetFormatter.out(System.out, queryResult);


    System.out.println("closing connection and model");
    aModel.close();
    aConn.close();  
}
private static void insert(final Connection theConn, final Graph theGraph) throws StardogException {
    theConn.begin();
    theConn.add().graph(theGraph);
    theConn.commit();
}

private static void remove(final Connection theConn, final Graph theGraph) throws StardogException {
    theConn.begin();
    theConn.remove().graph(theGraph);
    theConn.commit();
}
}


来源:https://stackoverflow.com/questions/16053904/example-of-stardog-sparql-insert-query-in-java

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