The MongoDB class

Introduction

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 "$".

Class synopsis

MongoDB {

/* Constants */

const int PROFILING_OFF = 0 ;

const int PROFILING_SLOW = 1 ;

const int PROFILING_ON = 2 ;

/* Fields */

public integer $w = 1 ;

public integer $wtimeout = 10000 ;

/* Methods */

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

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

public __construct ( Mongo $conn , string $name )

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

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

public array drop ( void )

public array dropCollection ( mixed $coll )

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

public bool forceError ( void )

public MongoCollection __get ( string $name )

public array getDBRef ( array $ref )

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

public int getProfilingLevel ( void )

public bool getSlaveOkay ( void )

public array lastError ( void )

public array listCollections ( void )

public array prevError ( void )

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

public array resetError ( void )

public MongoCollection selectCollection ( string $name )

public int setProfilingLevel ( int $level )

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

public string __toString ( void )

}

Predefined Constants

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.