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This document uses PHP Chinese website manual Release
(PECL mongo >=0.9.0)
MongoCollection::createDBRef — 创建一个数据库引用
$document_or_id
)
document_or_id
If an array or object is given, its _id field will be used as the reference ID. If a MongoId or scalar is given, it will be used as the reference ID.
返回一个数据库的引用数组。
如果提供了不包含 _id 字段的数组当做 document_or_id 参数,将会返回 NULL
。
Example #1 MongoCollection::createDBRef() 例子
<?php
$songs = $db -> songs ;
$playlists = $db -> playlists ;
// 为 song 创建引用
$manamana = $songs -> findOne (array( 'title' => 'Ma na ma na' ));
$refToSong = $songs -> createDBRef ( $manamana );
// 添加引用到我的播放列表
$playlists -> update (array( 'username' => 'me' ), array( '$push' => array( 'songlist' => $refToSong )));
?>