(PECL mongo >=0.9.0)
MongoDB::createDBRef — Creates a database reference
This method is a flexible interface for creating database refrences (see MongoDBRef).
collection
The collection to which the database reference will point.
a
Object or _id to which to create a reference. If an object or associative array is given, this will create a reference using the _id field.
Returns a database reference array.
Example #1 MongoDB::createDBRef() example
Example demonstrating how to programatically create a DB reference array from a document.
<?php
$articles = $db->articles;
$article = array(
'title' => 'Test article',
'description' => 'Test article description'
);
$articles->insert($article);
$ref = $db->createDBRef('articles', $article);
print_r($article);
print_r($ref);
?>
以上例程的输出类似于:
Array ( [title] => Test article [description] => Test article description [_id] => MongoId Object ( ) ) Array ( [$ref] => articles [$id] => MongoId Object ( ) )
Now the $ref can be stored on another document and retrieved later with MongoDB::getDBRef() or MongoCollection::getDBRef().
Example #2 MongoDB::createDBRef() example
Example demonstrating how to programatically create a DB reference from just an id.
<?php
$id = new MongoId('47cc67093475061e3d9536d2');
$ref = $db->createDBRef('articles', $id);
?>