PHP 5.4.33 Released

Tutorial

Introduction

This is the 10gen-supported PHP driver for MongoDB.

Here's a quick code sample that connects, inserts documents, queries for documents, iterates through query results, and disconnects from MongoDB. There are more details on each step in the tutorial below.

<?php

// connect
$m = new Mongo();

// select a database
$db $m->comedy;

// select a collection (analogous to a relational database's table)
$collection $db->cartoons;

// add a record
$obj = array( "title" => "Calvin and Hobbes""author" => "Bill Watterson" );
$collection->insert($obj);

// add another record, with a different "shape"
$obj = array( "title" => "XKCD""online" => true );
$collection->insert($obj);

// find everything in the collection
$cursor $collection->find();

// iterate through the results
foreach ($cursor as $obj) {
    echo 
$obj["title"] . "\n";
}

?>

This would output:

Calvin and Hobbes
XKCD

Making a Connection

To connect to the database server, use one of the following:

<?php

$connection 
= new Mongo(); // connects to localhost:27017
$connection = new Mongo"example.com" ); // connect to a remote host (default port)
$connection = new Mongo"example.com:65432" ); // connect to a remote host at a given port

?>
You do not have to explicitly disconnect from the database. When $connection goes out of scope, the connection will be closed automatically and any database resources it was using will be freed.

See Also

The manual chapter on connecting covers different types of connections.

The API documentation on the Mongo class and Mongo::__construct() give a comprehensive look at all possible options with a number of examples.

Getting a Database

To select a database, use:

<?php

$db 
$connection->dbname;

?>
The database does not need to be created in advance, you can create new databases by selecting them. Be careful of typos! You can inadvertently create a new database, which can cause confusing errors:
<?php

$db 
$connection->mybiglongdbname;
// do some stuff
$db $connection->mybiglongdbnme;
// now connected to a different database!

?>

See Also

The API documentation on the MongoDB class contains more information about database objects.

Getting A Collection

Getting a collection has the same syntax as getting a database:

<?php

$db 
$connection->baz;
$collection $db->foobar;

// or, more succinctly
$collection $connection->baz->foobar;

?>

See Also

The API documentation on the MongoCollection class contains more information about collection objects.

Inserting a Document

Associative arrays are the basic object that can be saved to a collection in the database. A somewhat random "document" might be:

<?php

$doc 
= array( "name" => "MongoDB",
   
"type" => "database",
   
"count" => 1,
   
"info" => (object)array( "x" => 203"y" => 102),
   
"versions" => array("0.9.7""0.9.8""0.9.9")
);

?>
Note that you can have nested arrays and objects.

To insert this document, use MongoCollection::insert():

<?php

$collection
->insert$doc );

?>

See Also

The API documentation on MongoCollection::insert() contains more information about inserting data.

Finding Documents using MongoCollection::findOne()

To show that the document we inserted in the previous step is there, we can do a simple MongoCollection::findOne() operation to get a single document from the collection. This method is useful when there only is one document matching the query or you are only interested in one result.

<?php

$obj 
$collection->findOne();
var_dump$obj );

?>
This should print:
array(5) {
  ["_id"]=>
  object(MongoId)#6 (0) {
  }
  ["name"]
  string(7) "MongoDB"
  ["type"]=>
  string(8) "database"
  ["count"]=>
  int(1)
  ["info"]=>
  array (2) {
    ["x"]=>
    int(203)
    ["y"]=>
    int(102)
  }
  ["versions"]
  array(3) {
    [0]=>
    string(5) "0.9.7"
    [1]=>
    string(5) "0.9.8"
    [2]=>
    string(5) "0.9.9"
  }
}

Note the _id field has been added automatically to your document. _id is the "primary key" field that is automatically populate for almost all documents in MongoDB.

See Also

The API documentation on MongoCollection::findOne() contains more information about finding data.

Adding Multiple Documents

In order to do more interesting things with queries, let's add multiple simple documents to the collection. These documents will just be

<?php

array( "i" => value );

?>
and we can do this fairly efficiently in a loop
<?php

for($i=0$i<100$i++) {
    
$collection->insert( array( "i" => $i ) );
}

?>

Notice that we can insert arrays with different key sets into the same collection. This aspect is what we mean when we say that MongoDB is "schema-free".

Counting Documents in A Collection

Now that we've inserted 101 documents (the 100 we did in the loop, plus the first one), we can check to see if we have them all using the MongoCollection::count() method.

<?php

echo $collection->count();

?>
and it should print 101.

Using a Cursor to Get All of the Documents

In order to get all the documents in the collection, we will use MongoCollection::find(). The find() method returns a MongoCursor object which allows us to iterate over the set of documents that matched our query. So to query all of the documents and print them out:

<?php

$cursor 
$collection->find();
foreach (
$cursor as $id => $value) {
    echo 
"$id: ";
    
var_dump$value );
}

?>
and that should print all 101 documents in the collection. $id is the _id field of a document, and $value is the document itself.

See Also

The API documentation on MongoCollection::find() contains more information about finding data.

Setting Criteria for a Query

We can create a query to pass to the MongoCollection::find() method to get a subset of the documents in our collection. For example, if we wanted to find the document for which the value of the "i" field is 71, we would do the following:

<?php

$query 
= array( "i" => 71 );
$cursor $collection->find$query );

while( 
$cursor->hasNext() ) {
    
var_dump$cursor->getNext() );
}

?>
and it should just print just one document
array(2) {
  ["_id"]=>
  object(MongoId)#6 (0) {
  }
  ["i"]=>
  int(71)
  ["_ns"]=>
  "testCollection"
}

Getting A Set of Documents With a Query

We can use the query to get a set of documents from our collection. For example, if we wanted to get all documents where "i" > 50, we could write:

<?php

$query 
= array( "i" => array( '$gt' => 50 ) ); //note the single quotes around '$gt'
$cursor $coll->find$query );

while( 
$cursor->hasNext() ) {
    
var_dump$cursor->getNext() );
}

?>
which should print the documents where i > 50. We could also get a range, say 20 < i <= 30:
<?php

$query 
= array( "i" => array( "\$gt" => 20"\$lte" => 30 ) );
$cursor $coll->find$query );

while( 
$cursor->hasNext() ) {
    
var_dump$cursor->getNext() );
}

?>
As it is easy to forget to escape the "$", you can also choose your own special character to use instead of '$'. Choose a character that will not occur in your key names, e.g. ":", and add the following line to php.ini:
mongo.cmd = ":"
Then the example above would look like:
<?php

$query 
= array( "i" => array( ":gt" => 20":lte" => 30 ) );

?>
You can also change it in your code using ini_set("mongo.cmd", ":"). Of course, you can also just use single quotes around the $.

Creating An Index

MongoDB supports indexes, and they are very easy to add on a collection. To create an index, you specify the field name and direction: ascending (1) or descending (-1). The following creates an ascending index on the "i" field:

<?php

$coll
->ensureIndex( array( "i" => ) );  // create index on "i"
$coll->ensureIndex( array( "i" => -1"j" => ) );  // index on "i" descending, "j" ascending

?>

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User Contributed Notes 3 notes

up
3
pgl at yoyo dot org
1 year ago
To use a collection with periods in its name, quote it with braces:

<?php
$m
= new MongoClient();

$cursor = $m->test->{'test.test'}->find();

## equivalent to the following:
#$db = $m->test;
#$collection = $db->{'test.test'};
#$cursor = $collection->find();

foreach ($cursor as $doc) {
   
print_r($doc);
?>
up
3
Josh Heidenreich
3 years ago
If you are getting "writing more" shown at random places on the screen, it's a MongoDB connector bug in 1.0.5.

Bug report: http://jira.mongodb.org/browse/PHP-91

Update to the latest connector driver and it should go away.
up
2
php at whoah dot net
4 years ago
Make sure array keys consecutive before inserting. As of 1.0.6 driver, the following will end up as an object of key:value pairs, instead of an array, because it's trying to maintain the 0 and 2 keys:

$array = array('a', 'b', 'c');
unset($array[1]);

$document = array(
'embedded' => $array,
);

// assuming local
$mongo = new Mongo();
$mongo->test->test->insert($document);

mongodb result:
{ "_id" : ObjectId(...), "embedded" : { "0" : "a", "2" : "c" } }

This is bad if you plan on indexing the embedded property as an array because objects and arrays are indexed differently.

Whether the behaviour will change or not, this is logged here: http://jira.mongodb.org/browse/PHP-104

If you know about it, it's not major, just use a sort() before inserting, or use array_* methods to remove elements instead of unset() -- anything that will re-adjust keys.
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