RDF API for PHP V0.9.3

Test: Manipulate DbModel

This example is part of the RAP - Rdf API for PHP documentation.

1. Connect to rdf database (e.g. Access via ODBC)

Set the system DSN for the particular database file (control pannel -> administrative tools -> data sources (odbc) -> system DSN).

// Include RAP define("RDFAPI_INCLUDE_DIR", "./../api/"); include(RDFAPI_INCLUDE_DIR . "RDFAPI.php"); // Connect to MsAccess database (rdf_db DSN) // using connection settings defined in constants.php : $rdf_database = ModelFactory::getDbStore();

Read more about Setting Database Connection.

2. Load and show a DbModel

// Load the model with modelURI "example1.rdf" $dbModel = $rdf_database->getModel("example1.rdf"); // Output the model as HTML table $dbModel->writeAsHtmlTable();

Note:

getModel() loads into memory only the modelURI and a database internal modelID, it also sets a database connection for the DbModel. This saves main memory and allows to gain advantage of database's indexing capabilities.

Output:

Base URI: http://www.w3.org/Home/Lassila.rdf#

Size: 4

No.

Subject

Predicate

Object

1.

Resource: http://www.w3.org/Home/Lassila

Resource: http://description.org/schema/Creator

Blank Node: b85740

2.

Blank Node: b85740

RDF Node: http://www.w3.org/1999/02/22-rdf-syntax-ns#type

Resource: http://description.org/schema/Person

3.

Blank Node: b85740

Resource: http://example.org/stuff/1.0/Name

Literal: Ora Lassila (rdf:datatype="http://www.w3.org/TR/xmlschema-2#string")

4.

Blank Node: b85740

Resource: http://example.org/stuff/1.0/Email

Literal: lassila@w3.org

3. Add a statement to the DbModel

// Ceate a new statement $statement = new Statement(new Resource("http://www.w3.org/Home/Lassila"), new Resource("http://description.org/schema/Description"), new Literal("Lassilas persönliche Homepage", "de")); // Add the statement to the DbModel $dbModel->add($statement); // Output the string serialization of the DbModel echo $dbModel->toStringIncludingTriples();

Output:

MemModel[baseURI=http://www.w3.org/Home/Lassila.rdf#; size=5] Triple(Resource("http://www.w3.org/Home/Lassila"), Resource("http://description.org/schema/Creator"), bNode("b85740")) Triple(bNode("b85740"), Resource("http://www.w3.org/1999/02/22-rdf-syntax-ns#type"), Resource("http://description.org/schema/Person")) Triple(bNode("b85740"), Resource("http://example.org/stuff/1.0/Name"), Literal("Ora Lassila", datatype="http://www.w3.org/TR/xmlschema-2#string")) Triple(bNode("b85740"), Resource("http://example.org/stuff/1.0/Email"), Literal("lassila@w3.org")) Triple(Resource("http://www.w3.org/Home/Lassila"), Resource("http://description.org/schema/Description"), Literal("Lassilas persönliche Homepage", lang="de"))

4. Search statements

// Search for statements having object $literal $literal = new Literal("Lassilas persönliche Homepage", "de"); $res = $dbModel->find(NULL, NULL, $literal); // Output the result $res->writeAsHtmlTable();

Output:

Base URI: http://www.w3.org/Home/Lassila.rdf#			Size: 1
No.	Subject	Predicate	Object
1.	Resource: http://www.w3.org/Home/Lassila	Resource: http://description.org/schema/Description	Literal: Lassilas persönliche Homepage (xml:lang="de")

5. Replace nodes and serialize the DbModel to XML/RDF

// replace a literal $dbModel->replace(NULL, NULL, new Literal("Lassilas persönliche Homepage", "de"), new Literal ("Lassila's personal Homepage", "en")); // Serialize to RDF $dbModel->writeAsHtml();

Output:

<?xml version='1.0' encoding='UTF-8'?>
<rdf:RDF
   xml:base="http://www.w3.org/Home/Lassila.rdf#"
   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
   xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
   xmlns:ns1="http://description.org/schema/"
   xmlns:ns2="http://example.org/stuff/1.0/">

<ns1:Person rdf:nodeID="b85740">
   <ns2:Email>lassila@w3.org</ns2:Email>
   <ns2:Name rdf:datatype="http://www.w3.org/TR/xmlschema-2#string">Ora Lassila</ns2:Name>
</ns1:Person>

<rdf:Description rdf:about="http://www.w3.org/Home/Lassila">
   <ns1:Creator rdf:nodeID="b85740"/>
   <ns1:Description xml:lang="en">Lassila's personal Homepage</ns1:Description>
</rdf:Description>

</rdf:RDF>

6. Remove a statement

$dbModel->remove(new Statement (new Resource("http://www.w3.org/Home/Lassila"), new Resource("http://description.org/schema/Description"), new Literal("Lassila's personal Homepage", "en"))); // Output the DbModel $dbModel->writeAsHtmlTable();

Output:

Base URI: http://www.w3.org/Home/Lassila.rdf#			Size: 4
No.	Subject	Predicate	Object
1.	Resource: http://www.w3.org/Home/Lassila	Resource: http://description.org/schema/Creator	Blank Node: b85740
2.	Blank Node: b85740	RDF Node: http://www.w3.org/1999/02/22-rdf-syntax-ns#type	Resource: http://description.org/schema/Person
3.	Blank Node: b85740	Resource: http://example.org/stuff/1.0/Name	Literal: Ora Lassila (rdf:datatype="http://www.w3.org/TR/xmlschema-2#string")
4.	Blank Node: b85740	Resource: http://example.org/stuff/1.0/Email	Literal: lassila@w3.org

7. Generate a MemModel and compare both models

// Generate a MemModel $memModel = $dbModel->getMemModel(); // Compare this DbModel withe the generated MemModel $res = $dbModel->equals($memModel); // Output the result if ($res) echo "models are equal"; else echo "models are different";

Output:

models are equal

8. Save DbModel to file

// Save model to file (XML/RDF) $dbModel->saveAs("Output.rdf"); // Save model to file (N3) $dbModel->saveAs("Output.n3"); // close the DbModel $dbModel->close();

Output:

Files: Output.rdf
Output.n3