(PECL mongo >=0.9.0)
MongoDB::getDBRef — Fetches the document pointed to by a database reference
$ref
   )
ref
     A database reference.
Returns the document pointed to by the reference.
Example #1 MongoDB::getDBRef() example
Example demonstrating how to get a database reference and what the expected input is.
<?php
 $ref = array(
   '$ref' => 'profiles',
   '$id' => new MongoId('47cc67093475061e3d9536d2')
 );
 
 $profile = $db->getDBRef($ref);
 ?>
See MongoDB::createDBRef() for more information about how to programatically create DB references.