Find a document with ObjectID in mongoDB

php mongodb mongodb-php
jwchang picture jwchang · Aug 16, 2011 · Viewed 37.5k times · Source

When I inserted some documents into a collection (without an ObjectID) mongoDB adds its own ObjectIDs.

I want to query a document by its unique ObjectID.

$db->collection_name->find(array('_id'=>'4e49fd8269fd873c0a000000')));

It does not work either with prefix of MongoID or ObjectID in front of '4e49fd8269fd873c0a000000'.

What is the proper way to query by ObjectID with mongoDB in PHP?

Answer

Phil picture Phil · Aug 16, 2011

Pretty sure you have to use a MongoId object, eg

$item = $collection->findOne(array(
    '_id' => new MongoId('4e49fd8269fd873c0a000000')));

The notes on the Querying page are a little obtuse but it does mention...

Unless the user has specified otherwise, the _id field is a MongoId. The most common mistake is attepting to use a string to match a MongoId. Keep in mind that these are two different datatypes, and will not match each other in the same way that the string "array()" is not the same as an empty array

Related questions

MongoDB and CodeIgniter

Can anyone assist in pointing me to a tutorial, library, etc. that will allow me to work with MongoDB from CodeIgniter?

Read More
Mongodb php get id of new document?

Creating a document: $db->collection->insert($content); // $newDocID = ??? I'm trying to get the new document's id. How? Thanks.

Read More
How to query mongo in php?

So I've got this simple login function that is trying to match email address with a password in the database and compare it with the user entered data via form. function login($email, $password){ $m = new Mongo("localhost"); $m->…

Read More