[edit] Last updated: Sat, 07 Jan 2012

The MongoDB class

(No version information available, might only be in SVN)

Einführung

Instances of this class are used to interact with a database. To get a database:


<?php

$m = new Mongo(); // connect
$db = $m->selectDB("example");

?>

Database names can use almost any character in the ASCII range. However, they cannot contain " ", "." or be the empty string. The name "system" is also reserved.

A few unusual, but valid, database names: "null", "[x,y]", "3", "\"", "/".

Unlike collection names, database names may contain "$".

Klassenbeschreibung

MongoDB {

/* Konstanten */

const int PROFILING_OFF = 0 ;

const int PROFILING_SLOW = 1 ;

const int PROFILING_ON = 2 ;

/* Fields */

public integer $MongoDB->w = 1 ;

public integer $wtimeout = 10000 ;

/* Methoden */

public array MongoDB::authenticate ( string $username , string $password )

public array MongoDB::command ( array $command [, array $options = array() ] )

MongoDB::__construct ( Mongo $conn , string $name )

public MongoCollection MongoDB::createCollection ( string $name [, bool $capped = FALSE [, int $size = 0 [, int $max = 0 ]]] )

public array MongoDB::createDBRef ( string $collection , mixed $a )

public array MongoDB::drop ( void )

public array MongoDB::dropCollection ( mixed $coll )

public array MongoDB::execute ( mixed $code [, array $args = array() ] )

public bool MongoDB::forceError ( void )

public MongoCollection MongoDB::__get ( string $name )

public array MongoDB::getDBRef ( array $ref )

public MongoGridFS MongoDB::getGridFS ([ string $prefix = "fs" ] )

public int MongoDB::getProfilingLevel ( void )

public bool MongoDB::getSlaveOkay ( void )

public array MongoDB::lastError ( void )

public array MongoDB::listCollections ( void )

public array MongoDB::prevError ( void )

public array MongoDB::repair ([ bool $preserve_cloned_files = FALSE [, bool $backup_original_files = FALSE ]] )

public array MongoDB::resetError ( void )

public MongoCollection MongoDB::selectCollection ( string $name )

public int MongoDB::setProfilingLevel ( int $level )

public bool MongoDB::setSlaveOkay ([ bool $ok = true ] )

public string MongoDB::__toString ( void )

}

Vordefinierte Konstanten

MongoDB Log Levels

MongoDB::PROFILING_OFF
0: Profiling is off.
MongoDB::PROFILING_SLOW
1: Profiling is on for slow operations (>100 ms).
MongoDB::PROFILING_ON
2: Profiling is on for all operations.

Fields

w 1

The number of servers to replicate a change to before returning success. Inherited by instances of MongoCollection derived from this. w functionality is only available in version 1.5.1+ of the MongoDB server and 1.0.8+ of the driver.

w is used whenever you perform a "safe" operation (MongoCollection::insert(), MongoCollection::update(), MongoCollection::remove(), MongoCollection::save(), and MongoCollection::ensureIndex() all support safe options). With the default value (1), a safe operation will return once the database server has the operation. If the server goes down before the operation has been replicated to a slave, it is possible to lose the operation forever. Thus, you can specify w to be higher than one and guarantee that at least one slave has the operation before it is considered successful.

For example, if w is 2, the main server and one slave must have a record of the operation or the driver will throw a MongoCursorException. It is tempting to set w to the total number of slaves + master, but then if one slave is down the op will fail and an exception will be thrown, so usually w=2 is safest (master+1 slave).

wtimeout 10000

The number of milliseconds to wait for MongoDB::$w replications to take place. Inherited by instances of MongoCollection derived from this. w functionality is only available in version 1.5.1+ of the MongoDB server and 1.0.8+ of the driver.

Unless wtimeout is set, the server waits forever for replicating to w servers to finish. The driver defaults to waiting for 10 seconds, you can change this value to alter its behavior.

Siehe auch

MongoDB core docs on » databases.

Inhaltsverzeichnis

MongoDB::authenticate — Log in to this database
MongoDB::command — Execute a database command
MongoDB::__construct — Creates a new database
MongoDB::createCollection — Creates a collection
MongoDB::createDBRef — Creates a database reference
MongoDB::drop — Drops this database
MongoDB::dropCollection — Drops a collection [deprecated]
MongoDB::execute — Runs JavaScript code on the database server.
MongoDB::forceError — Creates a database error
MongoDB::__get — Gets a collection
MongoDB::getDBRef — Fetches the document pointed to by a database reference
MongoDB::getGridFS — Fetches toolkit for dealing with files stored in this database
MongoDB::getProfilingLevel — Gets this database's profiling level
MongoDB::getSlaveOkay — Get slaveOkay setting for this database
MongoDB::lastError — Check if there was an error on the most recent db operation performed
MongoDB::listCollections — Get a list of collections in this database
MongoDB::prevError — Checks for the last error thrown during a database operation
MongoDB::repair — Repairs and compacts this database
MongoDB::resetError — Clears any flagged errors on the database
MongoDB::selectCollection — Gets a collection
MongoDB::setProfilingLevel — Sets this database's profiling level
MongoDB::setSlaveOkay — Change slaveOkay setting for this database
MongoDB::__toString — The name of this database

MongoDB::authenticate

Mongo::__toString

[edit] Last updated: Sat, 07 Jan 2012

add a note User Contributed Notes MongoDB

m dot espositoii at yahoo dot com 27-Aug-2011 03:11


With Mongo it'll automatically create the collection, so just start using it and it'll do the creation itself.



In other words... just use SelectCollection, if it doesn't exist, it will after that so you can drop it.

jeromakay at yahoo dot com 20-Jan-2011 12:19


based on what I've read and then applied, you don't have to specifically create a database or table, you just initialize it. 



Indeed, files are not being written inside /data/db, but they will the first moment you start adding data.



So, I'm taking as an example Twitter, with no db defined, I'm still going to have the db available if I run this code:



<?php



define('TWITTER_API_VERSION', 1);



date_default_timezone_set("Europe/Dublin");



try 

{

    $m = new Mongo(); // connect

    $db = $m->selectDB("example");

}

catch ( MongoConnectionException $e ) 

{

    echo '<p>Couldn\'t connect to mongodb, is the "mongo" process running?</p>';

    exit();

}



$updates = file_get_contents( "http://api.twitter.com/". TWITTER_API_VERSION ."/statuses/public_timeline.json" );

$updates = json_decode( $updates );



if ( $updates && is_array( $updates ) && count( $updates ) )

{

    foreach ( $updates as $update )

    {    

        $db->users->insert( $update );

    }

}



?>



Hope this was helpful!



Good luck!

Vladimir Ghetau

jonwage at gmail dot com 01-May-2010 11:56


Just a note that if you use selectDB() and only select it, the database will not be created. In PHPMongoDBAdmin(http://github.com/jwage/php-mongodb-admin) I wanted a way to create a database through a form so I needed to create a dummy collection and drop it in order for the database to be created. MongoDB has a drop() method but no create() method.



<?php

$mongo->selectDB('db')->createCollection('__tmp_collection_');

$mongo->selectDB('db')->dropCollection('__tmp_collection_');

?>



Any better way to do this?

add a note