CREATE INDEX 'nested_set_left' on 'nested_set' ( 'lft' );
CREATE INDEX 'nested_set_right' on 'nested_set' ( 'rgt' );
CREATE TABLE data (
'node_id' varchar(255) NOT NULL,
'melting_temp_k' float,
'boiling_temp_k' float
);
CREATE UNIQUE INDEX 'data_pri' on 'data' ( 'node_id' );
ENDSQL
);
// Create the example Persistent Object definition files and stub classes
$dbSchema = ezcDbSchema::createFromDb($dbh);
$writer1 = new ezcDbSchemaPersistentWriter(true);
$writer2 = new ezcDbSchemaPersistentClassWriter(true);
$writer1->saveToFile('files/po_defs', $dbSchema);
$writer2->saveToFile('files/classes', $dbSchema);
require 'files/classes/data.php';
// Setup the store and tree
$session = new ezcPersistentSession($dbh, new ezcPersistentCodeManager("files/po_defs"));
$store = new ezcTreePersistentObjectDataStore($session, 'data', 'node_id');
$tree = new ezcTreeDbNestedSet($dbh, 'nested_set', $store);
// Insert data
$metal = new data();
$tree->setRootNode($root = $tree->createNode('Metals', $metal));
$iron = new data();
$iron->setState(array('melting_temp_k' => 1811, 'boiling_temp_k' => 3134));
$root->addChild($tree->createNode('Fe', $iron));
// Fetch data
$fe = $tree->fetchNodeById('Fe')->data;
var_dump($fe);