1. Graph Developer's Guide for RDF Graph
  2. Conceptual and Usage Information
  3. RDF Graph Support for Eclipse RDF4J
  4. Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11 Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

This section includes the example queries for using Oracle RDF Graph Adapter for Eclipse RDF4J.

To run these examples, ensure that all the supporting libraries mentioned in Supporting libraries for using adapter with Java code are included in the CLASSPATH definition.

To run a query, you must execute the following actions:
  1. Include the example code in a Java source file.
  2. Define a CLASSPATH environment variable named CP to include the relevant jar files. For example, it may be defined as follows:
    setenv CP .:ojdbc8.jar:ucp.jar:oracle-rdf4j-adapter-4.2.1.jar:log4j-api-2.17.2.jar:log4j-core-2.17.2.jar:log4j-slf4j-impl-2.17.2.jar:slf4j-api-1.7.36.jar:eclipse-rdf4j-4.2.1-onejar.jar:commons-io-2.11.0.jar

    Note:

    The preceding setenv command assumes that the jar files are located in the current directory. You may need to alter the command to indicate the location of these jar files in your environment.
  3. Compile the Java source file. For example, to compile the source file Test.java, run the following command:
    javac -classpath $CP Test.java
  4. Run the compiled file on an RDF graph named TestModel in an existing schema-private network whose owner is SCOTT and name is NET1 by executing the following command:
    java -classpath $CP Test jdbc:oracle:thin:@localhost:1521:orcl scott  <password-for-scott> TestModel scott net1

Parent topic: RDF Graph Support for Eclipse RDF4J

8.11.1 Example 1: Basic Operations

Example 8-5 shows the BasicOper.java file, which performs some basic operations such as add and remove statements.

Example 8-5 Basic Operations

import java.io.IOException;
import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.common.iteration.CloseableIteration;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Statement;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.sail.SailException;

public class BasicOper {
  public static void main(String[] args) throws ConnectionSetupException, SQLException, IOException {
    PrintStream psOut = System.out;
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;
    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    OracleSailConnection conn = null;

    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);

      ValueFactory f = sr.getValueFactory();
      conn = store.getConnection();

      // create some resources and literals to make statements out of
      IRI p = f.createIRI("http://p");
      IRI domain = f.createIRI("http://www.w3.org/2000/01/rdf-schema#domain");
      IRI cls = f.createIRI("http://cls");
      IRI a = f.createIRI("http://a");
      IRI b = f.createIRI("http://b");
      IRI ng1 = f.createIRI("http://ng1");

      conn.addStatement(p, domain, cls);
      conn.addStatement(p, domain, cls, ng1);
      conn.addStatement(a, p, b, ng1);
      psOut.println("size for given contexts " + ng1 + ": " + conn.size(ng1));
      
      // returns OracleStatements
      CloseableIteration < ?extends Statement, SailException > it;
      int cnt;
      
      // retrieves all statements that appear in the repository(regardless of context)
      cnt = 0;
      it = conn.getStatements(null, null, null, false);
      while (it.hasNext()) {
        Statement stmt = it.next();
        psOut.println("getStatements: stmt#" + (++cnt) + ":" + stmt.toString());
      }
      it.close();
      conn.removeStatements(null, null, null, ng1);
      psOut.println("size of context " + ng1 + ":" + conn.size(ng1));
      conn.removeAll();
      psOut.println("size of store: " + conn.size());
    }
    
    finally {
      if (conn != null && conn.isOpen()) {
        conn.close();
      }
      if (op != null && op.getOracleDB() != null)

      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      if (sr != null) sr.shutDown();
      if (store != null) store.shutDown();
      if (op != null) op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP BasicOper.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP BasicOper jdbc:oracle:thin:@localhost:1521:ORCL scott <password-for-scott> TestModel scott net1

The expected output of the java command might appear as follows: 

size for given contexts http://ng1: 2
getStatements: stmt#1: (http://a, http://p, http://b) [http://ng1]
getStatements: stmt#2: (http://p, http://www.w3.org/2000/01/rdf-schema#domain, http://cls) [http://ng1]
getStatements: stmt#3: (http://p, http://www.w3.org/2000/01/rdf-schema#domain, http://cls) [null]
size of context http://ng1:0
size of store: 0

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.2 Example 2: Add a Data File in TRIG Format

Example 8-6 shows the LoadFile.java file, which demonstrates how to load a file in TRIG format.

Example 8-6 Add a Data File in TRIG Format

import java.io. * ;
import java.sql.SQLException;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;
import org.eclipse.rdf4j.repository.RepositoryException;
import org.eclipse.rdf4j.rio.RDFParseException;
import org.eclipse.rdf4j.sail.SailException;
import org.eclipse.rdf4j.rio.RDFFormat;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;

public class LoadFile {
  public static void main(String[] args) throws ConnectionSetupException,
    SQLException, SailException, RDFParseException, RepositoryException,
    IOException {
    
      PrintStream psOut = System.out;
      String jdbcUrl = args[0];
      String user = args[1];
      String password = args[2];
      String model = args[3];
      String trigFile = args[4];
      String networkOwner = (args.length > 6) ? args[5] : null;
      String networkName = (args.length > 6) ? args[6] : null;

 
      OraclePool op = null;
      OracleSailStore store = null;
      Repository sr = null;
      RepositoryConnection repConn = null;
 
      try {
        op = new OraclePool(jdbcUrl, user, password);
        store = new OracleSailStore(op, model, networkOwner, networkName);
        sr = new OracleRepository(store);
        repConn = sr.getConnection();
        psOut.println("testBulkLoad: start: before-load Size=" + repConn.size());
        repConn.add(new File(trigFile), "http://my.com/", RDFFormat.TRIG);
        repConn.commit();
        psOut.println("size " + Long.toString(repConn.size()));
      }
      finally {
        if (repConn != null) {
          repConn.close();
        }
        if (op != null) OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
        if (sr != null) sr.shutDown();
        if (store != null) store.shutDown();
        if (op != null) op.close();
      }
  }
}

For running this example, assume that a sample TRIG data file named test.trig was created as: 


@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>.
@prefix xsd: <http://www.w3.org/2001/XMLSchema#>.
@prefix swp: <http://www.w3.org/2004/03/trix/swp-1/>.
@prefix dc: <http://purl.org/dc/elements/1.1/>.
@prefix foaf: <http://xmlns.com/foaf/0.1/>.
@prefix ex: <http://example.org/>.
@prefix : <http://example.org/>.
# default graph
{
  <http://example.org/bob>   dc:publisher "Bob Hacker".
  <http://example.org/alice> dc:publisher "Alice Hacker".
} 
:bob{
    _:a foaf:mbox <mailto:bob@oldcorp.example.org>.
    } 
:alice{
      _:a foaf:name "Alice".
      _:a foaf:mbox <mailto:alice@work.example.org>.
      } 
:jack {
      _:a foaf:name "Jack".
      _:a foaf:mbox <mailto:jack@oracle.example.org>.
      }

To compile this example, execute the following command:

javac -classpath $CP LoadFile.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP LoadFile jdbc:oracle:thin:@localhost:1521:ORCL scott <password>  TestModel ./test.trig scott net1

The expected output of the java command might appear as follows: 

testBulkLoad: start: before-load Size=0
size 7

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.3 Example 3: Simple Query

Example 3: Simple Query shows the SimpleQuery.java file, which demonstrates how to perform a simple query.

Example 8-7 Simple Query


import java.io.IOException;
import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Literal;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.vocabulary.RDF;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;

public class SimpleQuery {
  public static void main(String[] args) throws ConnectionSetupException, SQLException, IOException {
    PrintStream psOut = System.out;
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;


    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;

    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);

      ValueFactory f = sr.getValueFactory();
      conn = sr.getConnection();

      // create some resources and literals to make statements out of
      IRI alice = f.createIRI("http://example.org/people/alice");
      IRI name = f.createIRI("http://example.org/ontology/name");
      IRI person = f.createIRI("http://example.org/ontology/Person");
      Literal alicesName = f.createLiteral("Alice");

      conn.clear(); // to start from scratch
      conn.add(alice, RDF.TYPE, person);
      conn.add(alice, name, alicesName);
      conn.commit();
      
      //run a query against the repository
      String queryString = 
        "PREFIX ex: <http://example.org/ontology/>\n" + 
        "SELECT * WHERE {?x ex:name ?y}\n" + 
        "ORDER BY ASC(STR(?y)) LIMIT 1 ";
      TupleQuery tupleQuery = conn.prepareTupleQuery(QueryLanguage.SPARQL, queryString);

      try (TupleQueryResult result = tupleQuery.evaluate()) {
        while (result.hasNext()) {
          BindingSet bindingSet = result.next();
          psOut.println("value of x: " + bindingSet.getValue("x"));
          psOut.println("value of y: " + bindingSet.getValue("y"));
        }
      }
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      sr.shutDown();
      store.shutDown();
      op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP SimpleQuery.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP SimpleQuery jdbc:oracle:thin:@localhost:1521:ORCL scott <password-for-scott> TestModel scott net1

The expected output of the java command might appear as follows: 


value of x: http://example.org/people/alice
value of y: "Alice"

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.4 Example 4: Simple Bulk Load

Example 8-8 shows the SimpleBulkLoad.java file, which demonstrates how to do a bulk load from NTriples data.

Example 8-8 Simple Bulk Load


import java.io. * ;
import java.sql.SQLException;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.Resource;
import org.eclipse.rdf4j.repository.RepositoryException;
import org.eclipse.rdf4j.rio.RDFParseException;
import org.eclipse.rdf4j.sail.SailException;
import org.eclipse.rdf4j.rio.RDFFormat;
import org.eclipse.rdf4j.repository.Repository;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;

public class SimpleBulkLoad {
  public static void main(String[] args) throws ConnectionSetupException, SQLException,
    SailException, RDFParseException, RepositoryException, IOException {
      PrintStream psOut = System.out;
      String jdbcUrl = args[0];
      String user = args[1];
      String password = args[2];
      String model = args[3];
      String filename = args[4]; // N-TRIPLES file
      String networkOwner = (args.length > 6) ? args[5] : null;
      String networkName = (args.length > 6) ? args[6] : null;


      OraclePool op = new OraclePool(jdbcUrl, user, password);
      OracleSailStore store = new OracleSailStore(op, model, networkOwner, networkName);
      OracleSailConnection osc = store.getConnection();
      Repository sr = new OracleRepository(store);
      ValueFactory f = sr.getValueFactory();

      try {
        psOut.println("testBulkLoad: start");

        FileInputStream fis = new
        FileInputStream(filename);

        long loadBegin = System.currentTimeMillis();
        IRI ng1 = f.createIRI("http://QuadFromTriple");
        osc.getBulkUpdateHandler().addInBulk(
        fis, "http://abc",  // baseURI
        RDFFormat.NTRIPLES, // dataFormat
        null,               // tablespaceName
        50,                 // batchSize
        null,               // flags
        ng1                 // Resource... for contexts
        );

        long loadEnd = System.currentTimeMillis();
        long size_no_contexts = osc.size((Resource) null);
        long size_all_contexts = osc.size();

        psOut.println("testBulkLoad: " + (loadEnd - loadBegin) +
         "ms. Size:" + " NO_CONTEXTS=" + size_no_contexts + " ALL_CONTEXTS=" + size_all_contexts);
        // cleanup
        osc.removeAll();
        psOut.println("size of store: " + osc.size());

      }
      finally {
        if (osc != null && osc.isOpen()) osc.close();
        if (op != null) OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
        if (sr != null) sr.shutDown();
        if (store != null) store.shutDown();
        if (op != null) op.close();
      }
  }
}

For running this example, assume that a sample ntriples data file named test.ntriples was created as: 


<urn:JohnFrench> <urn:name> "John".
<urn:JohnFrench> <urn:speaks> "French".
<urn:JohnFrench> <urn:height> <urn:InchValue>.
<urn:InchValue> <urn:value> "63".
<urn:InchValue> <urn:unit> "inch".
<http://data.linkedmdb.org/movie/onto/genreNameChainElem1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#first> <http://data.linkedmdb.org/movie/genre>.

To compile this example, execute the following command:

javac -classpath $CP SimpleBulkLoad.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP SimpleBulkLoad jdbc:oracle:thin:@localhost:1521:ORCL scott <password> TestModel ./test.ntriples scott net1

The expected output of the java command might appear as follows: 

testBulkLoad: start
testBulkLoad: 8222ms. 
Size: NO_CONTEXTS=0 ALL_CONTEXTS=6
size of store: 0

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.5 Example 5: Bulk Load RDF/XML

Example 5: Bulk Load RDF/XML shows the BulkLoadRDFXML.java file, which demonstrates how to do a bulk load from RDF/XML file.

Example 8-9 Bulk Load RDF/XML


import java.io. * ;
import java.sql.SQLException;
import org.eclipse.rdf4j.model.Resource;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;
import org.eclipse.rdf4j.repository.RepositoryException;
import org.eclipse.rdf4j.rio.RDFParseException;
import org.eclipse.rdf4j.sail.SailException;
import org.eclipse.rdf4j.rio.RDFFormat;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;

public class BulkLoadRDFXML {
  public static void main(String[] args) throws
    ConnectionSetupException, SQLException, SailException,
    RDFParseException, RepositoryException, IOException {
      PrintStream psOut = System.out;
      String jdbcUrl = args[0];
      String user = args[1];
      String password = args[2];
      String model = args[3];
      String rdfxmlFile = args[4]; // RDF/XML-format data file
      String networkOwner = (args.length > 6) ? args[5] : null;
      String networkName = (args.length > 6) ? args[6] : null;


      OraclePool op = null;
      OracleSailStore store = null;
      Repository sr = null;
      OracleSailConnection conn = null;
            
      try {
        op = new OraclePool(jdbcUrl, user, password);
        store = new OracleSailStore(op, model, networkOwner, networkName);
        sr = new OracleRepository(store);
        conn = store.getConnection();
        
        FileInputStream fis = new FileInputStream(rdfxmlFile);
        psOut.println("testBulkLoad: start: before-load Size=" + conn.size());
        long loadBegin = System.currentTimeMillis();
        conn.getBulkUpdateHandler().addInBulk(
          fis, 
          "http://abc",      // baseURI
          RDFFormat.RDFXML,  // dataFormat
          null,              // tablespaceName
          null,              // flags
          null,             //  StatusListener
          (Resource[]) null //  Resource...for contexts
        );

        long loadEnd = System.currentTimeMillis();
        psOut.println("testBulkLoad: " + (loadEnd - loadBegin) + "ms. Size=" + conn.size() + "\n");
      }
      finally {
        if (conn != null && conn.isOpen()) {
          conn.close();
        }
        if (op != null) OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
        if (sr != null) sr.shutDown();
        if (store != null) store.shutDown();
        if (op != null) op.close();
      }
  }
}

For running this example, assume that a sample file named RdfXmlData.rdfxml was created as: 


<?xml version="1.0"?>
<!DOCTYPE owl [     
  <!ENTITY owl  "http://www.w3.org/2002/07/owl#" >     
  <!ENTITY xsd  "http://www.w3.org/2001/XMLSchema#" >   
]> 
<rdf:RDF  
  xmlns     = "http://a/b#" xml:base  = "http://a/b#" xmlns:my  = "http://a/b#"  
  xmlns:owl = "http://www.w3.org/2002/07/owl#"  
  xmlns:rdf = "http://www.w3.org/1999/02/22-rdf-syntax-ns#"  
  xmlns:rdfs= "http://www.w3.org/2000/01/rdf-schema#"  
  xmlns:xsd = "http://www.w3.org/2001/XMLSchema#">  
  <owl:Class rdf:ID="Color">    
    <owl:oneOf rdf:parseType="Collection">      
      <owl:Thing rdf:ID="Red"/>      
      <owl:Thing rdf:ID="Blue"/>    
    </owl:oneOf>  
  </owl:Class>
</rdf:RDF>

To compile this example, execute the following command:

javac -classpath $CP BulkLoadRDFXML.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP BulkLoadRDFXML jdbc:oracle:thin:@localhost:1521:ORCL scott <password>  TestModel ./RdfXmlData.rdfxml scott net1

The expected output of the java command might appear as follows: 

testBulkLoad: start: before-load Size=0
testBulkLoad: 6732ms. Size=8

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.6 Example 6: SPARQL Ask Query

Example 6: SPARQL Ask Query shows the SparqlASK.java file, which demonstrates how to perform a SPARQL ASK query.

Example 8-10 SPARQL Ask Query

import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.OracleSailRepositoryConnection;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.vocabulary.RDFS;
import org.eclipse.rdf4j.query.BooleanQuery;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;

public class SparqlASK {
  public static void main(String[] args) throws ConnectionSetupException, SQLException {
    PrintStream psOut = System.out;
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;


    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;

    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);
      conn = sr.getConnection();
      OracleSailConnection osc = 
        (OracleSailConnection)((OracleSailRepositoryConnection) conn).getSailConnection();

      ValueFactory vf = sr.getValueFactory();
      IRI p = vf.createIRI("http://p");
      IRI cls = vf.createIRI("http://cls");

      conn.clear();
      conn.add(p, RDFS.DOMAIN, cls);
      conn.commit();

      osc.analyze();                 // analyze the semantic model
      osc.analyzeApplicationTable(); // and then the application table
      BooleanQuery tq = null;
      tq = conn.prepareBooleanQuery(QueryLanguage.SPARQL, "ASK { ?x ?p <http://cls> }");
      boolean b = tq.evaluate();
      psOut.println("\nAnswer is " + Boolean.toString(b));
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      sr.shutDown();
      store.shutDown();
      op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP SparqlASK.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP SparqlASK jdbc:oracle:thin:@localhost:1521:ORCL scott <password> TestModel scott net1

The expected output of the java command might appear as follows: 

Answer is true

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.7 Example 7: SPARQL CONSTRUCT Query

Example 8-11 shows the SparqlConstruct.java file, which demonstrates how to perform a SPARQL CONSTRUCT query.

Example 8-11 SPARQL CONSTRUCT Query


import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.OracleSailRepositoryConnection;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Statement;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.vocabulary.RDFS;
import org.eclipse.rdf4j.query.GraphQuery;
import org.eclipse.rdf4j.query.GraphQueryResult;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;

public class SparqlConstruct {
  public static void main(String[] args) throws ConnectionSetupException, SQLException {
    PrintStream psOut = System.out;
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;


    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;

    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);
      conn = sr.getConnection();

      ValueFactory vf = sr.getValueFactory();
      IRI p = vf.createIRI("http://p");
      IRI cls = vf.createIRI("http://cls");

      conn.clear();
      conn.add(p, RDFS.DOMAIN, cls);
      conn.commit();
      OracleSailConnection osc = 
        (OracleSailConnection)((OracleSailRepositoryConnection) conn).getSailConnection();
      osc.analyze();                 // analyze the RDF graph
      osc.analyzeApplicationTable(); // and then the application table
                                     
      GraphQuery tq = null;          // Construct Query
      tq = conn.prepareGraphQuery(QueryLanguage.SPARQL, 
        "CONSTRUCT {?x <http://new_eq_p> ?o } WHERE { ?x ?p ?o }");
      psOut.println("Start construct query");

      try (GraphQueryResult result = tq.evaluate()) {
        while (result.hasNext()) {
          Statement stmt = (Statement) result.next();
          psOut.println(stmt.toString());
        }
      }
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      sr.shutDown();
      store.shutDown();
      op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP SparqlConstruct.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP SparqlConstruct jdbc:oracle:thin:@localhost:1521:ORCL scott <password> TestModel scott net1

The expected output of the java command might appear as follows: 

Start construct query
(http://p, http://new_eq_p, http://cls)

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.8 Example 8: Named Graph Query

Example 8-12 shows the NamedGraph.java file, which demonstrates how to perform a Named Graph query.

Example 8-12 Named Graph Query


import java.io.File;
import java.io.IOException;
import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.OracleSailRepositoryConnection;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;
import org.eclipse.rdf4j.rio.RDFFormat;

public class NamedGraph {
  public static void main(String[] args) throws ConnectionSetupException, SQLException, IOException {
    PrintStream psOut = System.out;
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String trigFile = args[4]; // TRIG-format data file
    String networkOwner = (args.length > 6) ? args[5] : null;
    String networkName = (args.length > 6) ? args[6] : null;

    
    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;
    
    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);
      conn = sr.getConnection();

      conn.begin();
      conn.clear();

      // load the data incrementally since it is very small file
      conn.add(new File(trigFile), "http://my.com/", RDFFormat.TRIG);
      conn.commit();

      OracleSailConnection osc = (OracleSailConnection)((OracleSailRepositoryConnection) conn).getSailConnection();

      osc.analyze(); // analyze the RDF graph
      osc.analyzeApplicationTable(); // and then the application table
      TupleQuery tq = null;
      tq = conn.prepareTupleQuery(QueryLanguage.SPARQL,
             "PREFIX : <http://purl.org/dc/elements/1.1/>\n" +
             "SELECT ?g ?s ?p ?o\n" +
             "WHERE {?g :publisher ?o1 . GRAPH ?g {?s ?p ?o}}\n" +
             "ORDER BY ?g ?s ?p ?o");
      try (TupleQueryResult result = tq.evaluate()) {
        int idx = 0;
        while (result.hasNext()) {
          idx++;
          BindingSet bindingSet = result.next();
          psOut.print("\nsolution " + bindingSet.toString());
        }
        psOut.println("\ntotal # of solution " + Integer.toString(idx));
      }
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null,  networkOwner, networkName);
      sr.shutDown();
      store.shutDown();
      op.close();
    }
  }
}

For running this example, assume that the test.trig file in TRIG format has been created as follows: 


@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>.
@prefix xsd: <http://www.w3.org/2001/XMLSchema#>.
@prefix swp: <http://www.w3.org/2004/03/trix/swp-1/>.
@prefix dc: <http://purl.org/dc/elements/1.1/>.
@prefix foaf: <http://xmlns.com/foaf/0.1/>.
@prefix : <http://example.org/>.
# default graph
{
  :bobGraph    dc:publisher  "Bob Hacker" .
  :aliceGraph  dc:publisher  "Alice Hacker" .
}
 
:bobGraph {
  :bob foaf:mbox <mailto:bob@oldcorp.example.org> .
}
 
:aliceGraph {
  :alice foaf:name "Alice" .
  :alice foaf:mbox <mailto:alice@work.example.org> .
}
 
:jackGraph {
  :jack foaf:name "Jack" .
  :jack foaf:mbox <mailto:jack@oracle.example.org> .
}

To compile this example, execute the following command:

javac -classpath $CP NamedGraph.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP NamedGraph jdbc:oracle:thin:@localhost:1521:ORCL scott <password> TestModel ./test.trig scott net1

The expected output of the java command might appear as follows: 


solution 
[p=http://xmlns.com/foaf/0.1/mbox;s=http://example.org/alice;g=http://example.org/aliceGraph;o=mailto:alice@work.example.org]
solution 
[p=http://xmlns.com/foaf/0.1/name;s=http://example.org/alice;g=http://example.org/aliceGraph;o="Alice"]
solution 
[p=http://xmlns.com/foaf/0.1/mbox;s=http://example.org/bob;g=http://example.org/bobGraph;o=mailto:bob@oldcorp.example.org]
total # of solution 3

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.9 Example 9: Get COUNT of Matches

Example 8-13 shows the CountQuery.java file, which demonstrates how to perform a query that returns the total number (COUNT) of matches.

Example 8-13 Get COUNT of Matches

import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.OracleSailRepositoryConnection;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Literal;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.vocabulary.RDF;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;

public class CountQuery {
  public static void main(String[] args) throws
    ConnectionSetupException, SQLException 
  {
    PrintStream psOut = System.out;
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;


    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;
    
    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);
      conn = sr.getConnection();

      ValueFactory f = conn.getValueFactory();

      // create some resources and literals to make statements out of
      IRI alice = f.createIRI("http://example.org/people/alice");
      IRI name = f.createIRI("http://example.org/ontology/name");
      IRI person = f.createIRI("http://example.org/ontology/Person");
      Literal alicesName = f.createLiteral("Alice");

      conn.begin();
      // clear model to start fresh
      conn.clear();
      conn.add(alice, RDF.TYPE, person);
      conn.add(alice, name, alicesName);
      conn.commit();

      OracleSailConnection osc = 
        (OracleSailConnection)((OracleSailRepositoryConnection) conn).getSailConnection();
      osc.analyze();
      osc.analyzeApplicationTable();

      // Run a query and only return the number of matches (the count ! )
      String queryString = " SELECT (COUNT(*) AS ?totalCount) WHERE {?s ?p ?y} ";

      TupleQuery tupleQuery = conn.prepareTupleQuery(
      QueryLanguage.SPARQL, queryString);

      try (TupleQueryResult result = tupleQuery.evaluate()) {
        if (result.hasNext()) {
          BindingSet bindingSet = result.next();
          String totalCount = bindingSet.getValue("totalCount").stringValue();
          psOut.println("number of matches: " + totalCount);
        }
      }
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      sr.shutDown();
      store.shutDown();
      op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP CountQuery.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP CountQuery jdbc:oracle:thin:@localhost:1521:ORCL scott <password> TestModel scott net1

The expected output of the java command might appear as follows: 


number of matches: 2

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.10 Example 10: Specify Bind Variable for Constant in Query Pattern

Example 8-13 shows the BindVar.java file, which demonstrates how to perform a query that specifies a bind variable for a constant in the SPARQL query pattern.

Example 8-14 Specify Bind Variable for Constant in Query Pattern


import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Literal;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.vocabulary.RDF;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;

public class BindVar {
  public static void main(String[] args) throws ConnectionSetupException, SQLException {
    PrintStream psOut = System.out;
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;


    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;
    
    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);
      conn = sr.getConnection();
      ValueFactory f = conn.getValueFactory();

      conn.begin();
      conn.clear();

      // create some resources and literals to make statements out of
      
      // Alice
      IRI alice = f.createIRI("http://example.org/people/alice");
      IRI name = f.createIRI("http://example.org/ontology/name");
      IRI person = f.createIRI("http://example.org/ontology/Person");
      Literal alicesName = f.createLiteral("Alice");
      conn.add(alice, RDF.TYPE, person);
      conn.add(alice, name, alicesName);

      //Bob
      IRI bob = f.createIRI("http://example.org/people/bob");
      Literal bobsName = f.createLiteral("Bob");
      conn.add(bob, RDF.TYPE, person);
      conn.add(bob, name, bobsName);

      conn.commit();

      String queryString = 
        " PREFIX ex: <http://example.org/ontology/> " + 
        " Select ?name \n" + " WHERE \n" + " { SELECT * WHERE { ?person ex:name ?name} }\n" + 
        " ORDER BY ?name";

      TupleQuery tupleQuery = conn.prepareTupleQuery(
      QueryLanguage.SPARQL, queryString);

      // set binding for ?person = Alice
      tupleQuery.setBinding("person", alice);
      try (TupleQueryResult result = tupleQuery.evaluate()) {
        if (result.hasNext()) {
          BindingSet bindingSet = result.next();
          psOut.println("solution " + bindingSet.toString());
        }
      }

      // re-run with ?person = Bob
      tupleQuery.setBinding("person", bob);
      try (TupleQueryResult result = tupleQuery.evaluate()) {
        if (result.hasNext()) {
          BindingSet bindingSet = result.next();
          psOut.println("solution " + bindingSet.toString());
        }
      }
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      sr.shutDown();
      store.shutDown();
      op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP BindVar.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP BindVar jdbc:oracle:thin:@localhost:1521:ORCL scott  <password> TestModel scott net1

The expected output of the java command might appear as follows: 


solution [name="Alice";person=http://example.org/people/alice]
solution [name="Bob";person=http://example.org/people/bob]

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.11 Example 11: SPARQL Update

Example 8-15 shows the SparqlUpdate.java file, which demonstrates how to perform SPARQL Update statements.

Example 8-15 SPARQL Update

import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.query.Update;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;

public class SparqlUpdate {
  private static final String DATA_1 =
    "[p=http://example.org/ontology/name;g=urn:g1;x=http://example.org/people/Sue;y=\"Sue\"]" +
    "[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]";

  private static final String DATA_2 =
    "[p=http://example.org/ontology/name;g=urn:g1;x=http://example.org/people/Sue;y=\"Susan\"]" +
    "[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]";

  private static final String DATA_3 =
    "[p=http://example.org/ontology/name;g=urn:g1;x=http://example.org/people/Sue;y=\"Susan\"]" +
    "[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]" +
    "[p=http://example.org/ontology/name;g=urn:g2;x=http://example.org/people/Sue;y=\"Susan\"]" +
    "[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g2;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]";

  private static final String DATA_4 = 
    "[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]" +
    "[p=http://example.org/ontology/name;g=urn:g2;x=http://example.org/people/Sue;y=\"Susan\"]" +
    "[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g2;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]";

  private static final String DATA_5 =
    "[p=http://example.org/ontology/name;g=urn:g1;x=http://example.org/people/Sue;y=\"Susan\"]" +
    "[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]" +
    "[p=http://example.org/ontology/name;g=urn:g2;x=http://example.org/people/Sue;y=\"Susan\"]" +
    "[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g2;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]";
  
  private static String getRepositoryData(RepositoryConnection conn, PrintStream out) 
  {
    String dataStr = "";
    String queryString = "SELECT * WHERE { GRAPH ?g { ?x ?p ?y } } ORDER BY ?g ?x ?p ?y";
    TupleQuery tupleQuery = conn.prepareTupleQuery(QueryLanguage.SPARQL, queryString);
    try (TupleQueryResult result = tupleQuery.evaluate()) {
      while (result.hasNext()) {
        BindingSet bindingSet = result.next();
        out.println(bindingSet.toString());
        dataStr += bindingSet.toString();
      }
    }
    return dataStr;
  }
  public static void main(String[] args) throws
    ConnectionSetupException, SQLException 
  {
    PrintStream out = new PrintStream(System.out);
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;


    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;
    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);
      conn = sr.getConnection();

      conn.clear(); // to start from scratch
      
      // Insert some initial data
      String updString = "PREFIX people: <http://example.org/people/>\n" +
                         "PREFIX    ont: <http://example.org/ontology/>\n" +
                         "INSERT DATA { GRAPH <urn:g1> { \n" + 
                         "              people:Sue a ont:Person; \n" + 
                         "                ont:name \"Sue\" . } }";
      Update upd = conn.prepareUpdate(QueryLanguage.SPARQL, updString);
      upd.execute();
      conn.commit();
      String repositoryData = getRepositoryData(conn, out);
      if (! (DATA_1.equals(repositoryData)) ) out.println("DATA_1 mismatch");
      // Change Sue's name to Susan
      updString = "PREFIX people: <http://example.org/people/>\n" +
                  "PREFIX    ont: <http://example.org/ontology/>\n" +
                  "DELETE { GRAPH ?g { ?s ont:name ?n } }\n" +
                  "INSERT { GRAPH ?g { ?s ont:name \"Susan\" } }\n" +
                  "WHERE  { GRAPH ?g { ?s ont:name ?n FILTER (?n = \"Sue\") }}";
      upd = conn.prepareUpdate(QueryLanguage.SPARQL, updString);
      upd.execute();
      conn.commit();
      repositoryData = getRepositoryData(conn, out);
      if (! (DATA_2.equals(repositoryData)) ) out.println("DATA_2 mismatch");

      // Copy to contents of g1 to a new graph g2
      updString = "PREFIX people: <http://example.org/people/>\n" +
                  "PREFIX ont: <http://example.org/ontology/>\n" +
                  "COPY <urn:g1> TO <urn:g2>";
      upd = conn.prepareUpdate(QueryLanguage.SPARQL, updString);
      upd.execute();
      conn.commit();

      repositoryData = getRepositoryData(conn, out);
      if (! (DATA_3.equals(repositoryData)) ) out.println("DATA_3 mismatch");

      // Delete ont:name triple from graph g1
      updString = "PREFIX people: <http://example.org/people/>\n" + 
                  "PREFIX  ont: <http://example.org/ontology/>\n" +
                  "DELETE DATA { GRAPH <urn:g1> { people:Sue ont:name \"Susan\" } }";
      upd = conn.prepareUpdate(QueryLanguage.SPARQL, updString);
      upd.execute();
      conn.commit();
      repositoryData = getRepositoryData(conn, out);
      if (! (DATA_4.equals(repositoryData)) ) out.println("DATA_4 mismatch");

      // Add contents of g2 to g1
      updString = "PREFIX people: <http://example.org/people/>\n" +
                  "PREFIX    ont: <http://example.org/ontology/>\n" +
                  "ADD <urn:g2> TO <urn:g1>";
      upd = conn.prepareUpdate(QueryLanguage.SPARQL, updString);
      upd.execute();
      conn.commit();
      repositoryData = getRepositoryData(conn, out);
      if (! (DATA_5.equals(repositoryData)) ) out.println("DATA_5 mismatch");
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      sr.shutDown();
      store.shutDown();
      op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP SparqlUpdate.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP SparqlUpdate jdbc:oracle:thin:@localhost:1521:ORCL scott <password> TestModel scott net1

The expected output of the java command might appear as follows: 

[p=http://example.org/ontology/name;g=urn:g1;x=http://example.org/people/Sue;y="Sue"]
[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]
[p=http://example.org/ontology/name;g=urn:g1;x=http://example.org/people/Sue;y="Susan"]
[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]
[p=http://example.org/ontology/name;g=urn:g1;x=http://example.org/people/Sue;y="Susan"]
[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]
[p=http://example.org/ontology/name;g=urn:g2;x=http://example.org/people/Sue;y="Susan"]
[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g2;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]
[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]
[p=http://example.org/ontology/name;g=urn:g2;x=http://example.org/people/Sue;y="Susan"]
[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g2;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]
[p=http://example.org/ontology/name;g=urn:g1;x=http://example.org/people/Sue;y="Susan"]
[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g1;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]
[p=http://example.org/ontology/name;g=urn:g2;x=http://example.org/people/Sue;y="Susan"]
[p=http://www.w3.org/1999/02/22-rdf-syntax-ns#type;g=urn:g2;x=http://example.org/people/Sue;y=http://example.org/ontology/Person]

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.12 Example 12: Oracle Hint

Example 8-16 shows the OracleHint.java file, which demonstrates how to use Oracle hint in a SPARQL query or a SPARQL update.

Example 8-16 Oracle Hint

import java.sql.SQLException;
import oracle.rdf4j.adapter.OracleDB;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.query.Update;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;

public class OracleHint {
  public static void main(String[] args) throws ConnectionSetupException, SQLException {
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;


    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;
    
    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);
      conn = sr.getConnection();

      conn.clear(); // to start from scratch
      
      // Insert some initial data
      String updString = 
        "PREFIX ex: <http://example.org/>\n" +
        "INSERT DATA {  " +
        "  ex:a ex:p1 ex:b . " +
        "  ex:b ex:p1 ex:c . " + 
        "  ex:c ex:p1 ex:d . " +
        "  ex:d ex:p1 ex:e . " +
        "  ex:e ex:p1 ex:f . " + 
        "  ex:f ex:p1 ex:g . " + 
        "  ex:g ex:p1 ex:h . " + 
        "  ex:h ex:p1 ex:i . " + 
        "  ex:i ex:p1 ex:j . " + 
        "  ex:j ex:p1 ex:k . " + 
        "}";
      Update upd = conn.prepareUpdate(QueryLanguage.SPARQL, updString);
      upd.execute();
      conn.commit();
      
      // default behavior for property path is 10 hop max, so we get 11 results
      String sparql = 
        "PREFIX ex: <http://example.org/>\n" + 
        "SELECT (COUNT(*) AS ?cnt)\n" + 
        "WHERE { ex:a ex:p1* ?y }";
      
      TupleQuery tupleQuery = conn.prepareTupleQuery(QueryLanguage.SPARQL, sparql);

      try (TupleQueryResult result = tupleQuery.evaluate()) {
        while (result.hasNext()) {
          BindingSet bindingSet = result.next();
          if (11 != Integer.parseInt(bindingSet.getValue("cnt").stringValue())) System.out.println("cnt mismatch: expecting 11");
        }
      }

      // ORACLE_SEM_FS_NS prefix hint to use parallel(2) and dynamic_sampling(6)
      // ORACLE_SEM_SM_NS prefix hint to use a 5 hop max and to use CONNECT BY instead of simple join
      sparql = 
        "PREFIX ORACLE_SEM_FS_NS: <http://oracle.com/semtech#dop=2,ods=6>\n" +
        "PREFIX ORACLE_SEM_SM_NS: <http://oracle.com/semtech#all_max_pp_depth(5),all_disable_pp_sj>\n" +
        "PREFIX ex: <http://example.org/>\n" + 
        "SELECT (COUNT(*) AS ?cnt)\n" + 
        "WHERE { ex:a ex:p1* ?y }";
      
      tupleQuery = conn.prepareTupleQuery(QueryLanguage.SPARQL, sparql, "http://example.org/");

      try (TupleQueryResult result = tupleQuery.evaluate()) {
        while (result.hasNext()) {
          BindingSet bindingSet = result.next();
          if (6 != Integer.parseInt(bindingSet.getValue("cnt").stringValue())) System.out.println("cnt mismatch: expecting 6");
        }
      }

      // query options for SPARQL Update      
      sparql = 
        "PREFIX ORACLE_SEM_UM_NS: <http://oracle.com/semtech#parallel(2)>\n" +
        "PREFIX ORACLE_SEM_SM_NS: <http://oracle.com/semtech#all_max_pp_depth(5),all_disable_pp_sj>\n" +
        "PREFIX ex: <http://example.org/>\n" + 
        "INSERT { GRAPH ex:g1 { ex:a ex:reachable ?y } }\n" + 
        "WHERE { ex:a ex:p1* ?y }";

      Update u = conn.prepareUpdate(sparql);
      u.execute();

      // graph ex:g1 should have 6 results because of all_max_pp_depth(5)
      sparql = 
        "PREFIX ex: <http://example.org/>\n" + 
        "SELECT (COUNT(*) AS ?cnt)\n" + 
        "WHERE { GRAPH ex:g1 { ?s ?p ?o } }";
      
      tupleQuery = conn.prepareTupleQuery(QueryLanguage.SPARQL, sparql, "http://example.org/");

      try (TupleQueryResult result = tupleQuery.evaluate()) {
        while (result.hasNext()) {
          BindingSet bindingSet = result.next();
          if (6 != Integer.parseInt(bindingSet.getValue("cnt").stringValue())) System.out.println("cnt mismatch: expecting 6");
        }
      }
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      sr.shutDown();
      store.shutDown();
      op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP OracleHint.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP OracleHint jdbc:oracle:thin:@localhost:1521:ORCL scott <password> TestModel scott net1

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.13 Example 13: Using JDBC Bind Values

Example 8-17 shows the JDBCBindVar.java file, which demonstrates how to use JDBC bind values.

Example 8-17 Using JDBC Bind Values

import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OracleDB;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Literal;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.vocabulary.RDF;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;

public class JDBCBindVar {

  public static void main(String[] args) throws ConnectionSetupException, SQLException {
    PrintStream psOut = System.out;
    
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;
    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null; 

    try {
      op = new OraclePool(jdbcUrl, user, password);
      store = (networkName == null) ? new OracleSailStore(op, model) : new OracleSailStore(op, model, networkOwner, networkName);   
      sr = new OracleRepository(store);
      conn = sr.getConnection();

      ValueFactory f = conn.getValueFactory();
      
      conn.begin();
      conn.clear();
  
      // create some resources and literals to make statements out of
      // Alice
      IRI alice = f.createIRI("http://example.org/people/alice");
      IRI name = f.createIRI("http://example.org/ontology/name");
      IRI person = f.createIRI("http://example.org/ontology/Person");
      Literal alicesName = f.createLiteral("Alice");   
      conn.add(alice, RDF.TYPE, person);
      conn.add(alice, name, alicesName);
      
      //Bob
      IRI bob = f.createIRI("http://example.org/people/bob");
      Literal bobsName = f.createLiteral("Bob");   
      conn.add(bob, RDF.TYPE, person);
      conn.add(bob, name, bobsName);
      
      conn.commit();
      
      // Query using USE_BIND_VAR=JDBC option for JDBC bind values
      // Simple BIND clause for ?person marks ?person as a bind variable
      String queryString =
        " PREFIX ORACLE_SEM_SM_NS: <http://oracle.com/semtech#USE_BIND_VAR=JDBC>\n" +
        " PREFIX ex: <http://example.org/ontology/>\n" +
        " Select ?name \n" +
        " WHERE \n" +
        " { SELECT * WHERE { \n" +
        "     BIND (\"\" AS ?person) \n" +
        "     ?person ex:name ?name } \n" +
        " }\n" +
        " ORDER BY ?name";      
      TupleQuery tupleQuery = conn.prepareTupleQuery(
          QueryLanguage.SPARQL, queryString);
      
      // set binding for ?person = Alice
      tupleQuery.setBinding("person", alice);
      try (TupleQueryResult result = tupleQuery.evaluate()) {
        if (result.hasNext()) {
          BindingSet bindingSet = result.next();
          psOut.println("solution " + bindingSet.toString());
        }
      }
      
      // re-run with ?person = Bob
      tupleQuery.setBinding("person", bob);
      try (TupleQueryResult result = tupleQuery.evaluate()) {
        if (result.hasNext()) {
          BindingSet bindingSet = result.next();
          psOut.println("solution " + bindingSet.toString());        
        }
      }
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      if (op != null) {
        OracleDB oracleDB = op.getOracleDB();
        if (networkName == null)
          OracleUtils.dropSemanticModelAndTables(oracleDB, model);
        else
          OracleUtils.dropSemanticModelAndTables(oracleDB, model, null, null, networkOwner, networkName);
        op.returnOracleDBtoPool(oracleDB);
      }
      sr.shutDown();
      store.shutDown();
      op.close();    
      }
  }
}

To compile this example, execute the following command:

javac -classpath $CP JDBCBindVar.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP JDBCBindVar jdbc:oracle:thin:@localhost:1521:ORCL scott <password-for-scott> TestModel scott net1

The expected output of the Java command might appear as follows:

solution [name="Alice";person=http://example.org/people/alice]
solution [name="Bob";person=http://example.org/people/bob]

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.14 Example 14: Simple Inference

Example 8-18 shows the SimpleInference.java file, which shows inference for a single RDF graph using the OWL2RL rule base.

Example 8-18 Simple Inference

import java.io.IOException;
import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Literal;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.vocabulary.RDF;
import org.eclipse.rdf4j.model.vocabulary.RDFS;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;
import oracle.rdf4j.adapter.Attachment;
import oracle.rdf4j.adapter.OracleSailConnection;
import oracle.rdf4j.adapter.OracleSailRepositoryConnection;

public class SimpleInference {
  public static void main(String[] args) throws ConnectionSetupException, SQLException, IOException {
    PrintStream psOut = System.out;
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String networkOwner = (args.length > 5) ? args[4] : null;
    String networkName = (args.length > 5) ? args[5] : null;

    OraclePool op = null;
    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;

    try {
      op = new OraclePool(jdbcUrl, user, password);

      // create a single-model, single-rulebase OracleSailStore object
      Attachment attachment = Attachment.createInstance(Attachment.NO_ADDITIONAL_MODELS, new String[] {"OWL2RL"});
      store = new OracleSailStore(op, model, attachment, networkOwner, networkName);
      sr = new OracleRepository(store);

      ValueFactory f = sr.getValueFactory();
      conn = sr.getConnection();

      // create some resources and literals to make statements out of
      IRI alice = f.createIRI("http://example.org/people/alice");
      IRI bob = f.createIRI("http://example.org/people/bob");
      IRI friendOf = f.createIRI("http://example.org/ontology/friendOf");
      IRI Person = f.createIRI("http://example.org/ontology/Person");
      IRI Woman = f.createIRI("http://example.org/ontology/Woman");
      IRI Man = f.createIRI("http://example.org/ontology/Man");

      conn.clear(); // to start from scratch

      // add some statements to the RDF graph
      conn.add(alice, RDF.TYPE, Woman);
      conn.add(bob, RDF.TYPE, Man);
      conn.add(alice, friendOf, bob);
      conn.commit();

      OracleSailConnection osc = (OracleSailConnection)((OracleSailRepositoryConnection)conn).getSailConnection();

      // perform inference (this will not generate any inferred triples)
      osc.performInference();   

      // prepare a query to run against the repository
      String queryString = 
        "PREFIX ex: <http://example.org/ontology/>\n" + 
        "SELECT * WHERE {?x ex:friendOf ?y . ?x a ex:Person . ?y a ex:Person}\n" ;
      TupleQuery tupleQuery = conn.prepareTupleQuery(QueryLanguage.SPARQL, queryString);

      // run the query: no results will be returned because nobody is a Person
      try (TupleQueryResult result = tupleQuery.evaluate()) {
        int resultCount = 0;
        while (result.hasNext()) {
          resultCount++;
          BindingSet bindingSet = result.next();
          psOut.println("value of x: " + bindingSet.getValue("x"));
          psOut.println("value of y: " + bindingSet.getValue("y"));
        }
        psOut.println("number of results: " + resultCount);
      }

      // add class hierarchy
      conn.add(Man, RDFS.SUBCLASSOF, Person);
      conn.add(Woman, RDFS.SUBCLASSOF, Person);
      conn.commit();

      // perform inference again
      osc.performInference();   

      // run the same query again: returns some results because alice and bob now belong to superclass Person
      try (TupleQueryResult result = tupleQuery.evaluate()) {
        while (result.hasNext()) {
          BindingSet bindingSet = result.next();
          psOut.println("value of x: " + bindingSet.getValue("x"));
          psOut.println("value of y: " + bindingSet.getValue("y"));
        }
      }
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      sr.shutDown();
      store.shutDown();
      op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP SimpleInference.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP SimpleInference jdbc:oracle:thin:@localhost:1521:ORCL scott <password-for-scott> TestModel scott net1

The expected output of the Java command might appear as follows:

number of results: 0
value of x: http://example.org/people/alice
value of y: http://example.org/people/bob

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J

8.11.15 Example 15: Simple Graph Collection

Example 8-19 shows the SimpleVirtualModel.java file, which shows the creation and use of an RDF graph collection consisting of two RDF graphs.

Example 8-19 Simple Graph Collection

import java.io.IOException;
import java.io.PrintStream;
import java.sql.SQLException;
import oracle.rdf4j.adapter.OraclePool;
import oracle.rdf4j.adapter.OracleRepository;
import oracle.rdf4j.adapter.OracleSailStore;
import oracle.rdf4j.adapter.exception.ConnectionSetupException;
import oracle.rdf4j.adapter.utils.OracleUtils;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.vocabulary.RDF;
import org.eclipse.rdf4j.model.vocabulary.RDFS;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.QueryLanguage;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;
import oracle.rdf4j.adapter.Attachment;

public class SimpleVirtualModel {
  public static void main(String[] args) throws ConnectionSetupException, SQLException, IOException {
    PrintStream psOut = System.out;
    String jdbcUrl = args[0];
    String user = args[1];
    String password = args[2];
    String model = args[3];
    String model2 = args[4];
    String virtualModelName = args[5];
    String networkOwner = (args.length > 7) ? args[6] : null;
    String networkName = (args.length > 7) ? args[7] : null;

    OraclePool op = null;

    OracleSailStore store = null;
    Repository sr = null;
    RepositoryConnection conn = null;

    OracleSailStore store2 = null;
    Repository sr2 = null;
    RepositoryConnection conn2 = null;

    OracleSailStore vmStore = null;
    Repository vmSr = null;
    RepositoryConnection vmConn = null;

    try {
      op = new OraclePool(jdbcUrl, user, password);

      // create two RDF graphs and then an RDF graph collection that uses those two graphs

      // create the first RDF grapj
      store = new OracleSailStore(op, model, networkOwner, networkName);
      sr = new OracleRepository(store);
      ValueFactory f = sr.getValueFactory();
      conn = sr.getConnection();
	  
      // create the second RDF graph (this one will be used as an additional graph in the attachment object)
      store2 = new OracleSailStore(op, model2, networkOwner, networkName);
      sr2 = new OracleRepository(store2);
      conn2 = sr2.getConnection();

      // create a two-graph RDF graph collection OracleSailStore object
      Attachment attachment = Attachment.createInstance(model2);
      vmStore = new OracleSailStore(op, model, /*ignored*/true, /*useVirtualModel*/true, virtualModelName, attachment, networkOwner, networkName);
      vmSr = new OracleRepository(vmStore);
      vmConn = vmSr.getConnection();

      // create some resources and literals to make statements out of
      IRI alice = f.createIRI("http://example.org/people/alice");
      IRI bob = f.createIRI("http://example.org/people/bob");
      IRI friendOf = f.createIRI("http://example.org/ontology/friendOf");
      IRI Person = f.createIRI("http://example.org/ontology/Person");
      IRI Woman = f.createIRI("http://example.org/ontology/Woman");
      IRI Man = f.createIRI("http://example.org/ontology/Man");

      // clear any data (in case any of the two non-virtual models were already present)
      conn.clear();
      conn2.clear();

      // add some statements to the first RDF model
      conn.add(alice, RDF.TYPE, Woman);
      conn.add(bob, RDF.TYPE, Man);
      conn.add(alice, friendOf, bob);
      conn.commit();

      // prepare a query to run against the virtual model repository
      String queryString = 
        "PREFIX ex: <http://example.org/ontology/>\n" + 
        "SELECT * WHERE {" + 
        "?x ex:friendOf ?y . ?x rdf:type/rdfs:subClassOf* ?xC . ?y rdf:type/rdfs:subClassOf* ?yC" + 
        "} ORDER BY ?x ?xC ?y ?yC\n" ;
        ;
      TupleQuery tupleQuery = vmConn.prepareTupleQuery(QueryLanguage.SPARQL, queryString);

      // run the query: no results will be returned because nobody is a Person
      try (TupleQueryResult result = tupleQuery.evaluate()) {
        int resultCount = 0;
        while (result.hasNext()) {
          resultCount++;
          BindingSet bindingSet = result.next();
          psOut.println("values of x | xC | y | yC: " + 
        		  bindingSet.getValue("x") + " | " + bindingSet.getValue("xC") + " | " + 
        		  bindingSet.getValue("y") + " | " + bindingSet.getValue("yC"));
        }
        psOut.println("number of results: " + resultCount);
      }

      // add class hierarchy info to the second model
      conn2.add(Man, RDFS.SUBCLASSOF, Person);
      conn2.add(Woman, RDFS.SUBCLASSOF, Person);
      conn2.commit();

      // run the same query again: returns some additional info in the results
      try (TupleQueryResult result = tupleQuery.evaluate()) {
    	int resultCount = 0;
        while (result.hasNext()) {
          resultCount++;
          BindingSet bindingSet = result.next();
          psOut.println("values of x | xC | y | yC: " + 
        		  bindingSet.getValue("x") + " | " + bindingSet.getValue("xC") + " | " + 
        		  bindingSet.getValue("y") + " | " + bindingSet.getValue("yC"));
        }
        psOut.println("number of results: " + resultCount);
      }
    }
    finally {
      if (conn != null && conn.isOpen()) {
        conn.clear();
        conn.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model, null, null, networkOwner, networkName);
      sr.shutDown();
      store.shutDown();

      if (conn2 != null && conn2.isOpen()) {
          conn2.clear();
          conn2.close();
      }
      OracleUtils.dropSemanticModelAndTables(op.getOracleDB(), model2, null, null, networkOwner, networkName);
      sr2.shutDown();
      store2.shutDown();
      
      vmSr.shutDown();
      vmStore.shutDown();

      op.close();
    }
  }
}

To compile this example, execute the following command:

javac -classpath $CP SimpleVirtualModel.java

To run this example for an existing schema-private network whose owner is SCOTT and name is NET1, execute the following command:

java -classpath $CP SimpleVirtualModel jdbc:oracle:thin:@localhost:1521:ORCL scott <password-for-scott> TestModel TestOntology TestVM scott net1

The expected output of the Java command might appear as follows:

values of x | xC | y | yC: http://example.org/people/alice | http://example.org/ontology/Woman | http://example.org/people/bob | http://example.org/ontology/Man
number of results: 1
values of x | xC | y | yC: http://example.org/people/alice | http://example.org/ontology/Person | http://example.org/people/bob | http://example.org/ontology/Man
values of x | xC | y | yC: http://example.org/people/alice | http://example.org/ontology/Person | http://example.org/people/bob | http://example.org/ontology/Person
values of x | xC | y | yC: http://example.org/people/alice | http://example.org/ontology/Woman | http://example.org/people/bob | http://example.org/ontology/Man
values of x | xC | y | yC: http://example.org/people/alice | http://example.org/ontology/Woman | http://example.org/people/bob | http://example.org/ontology/Person
number of results: 4

Parent topic: Example Queries Using Oracle RDF Graph Adapter for Eclipse RDF4J