The MongoDB class

(PECL mongo >=0.9.0)

Introduction

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

Example #1 Selecting a database


<?php

$m = new MongoClient(); // 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 authenticate ( string $username , string $password ) : array

public command ( array $command [, array $options = array() [, string &$hash ]] ) : array

public __construct ( MongoClient $conn , string $name )

public createCollection ( string $name [, array $options ] ) : MongoCollection

public createDBRef ( string $collection , mixed $document_or_id ) : array

public drop ( void ) : array

public dropCollection ( mixed $coll ) : array

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

public forceError ( void ) : bool

public __get ( string $name ) : MongoCollection

public getCollectionInfo ([ array $options = array() ] ) : array

public getCollectionNames ([ array $options = array() ] ) : array

public getDBRef ( array $ref ) : array

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

public getProfilingLevel ( void ) : int

public getReadPreference ( void ) : array

public getSlaveOkay ( void ) : bool

public getWriteConcern ( void ) : array

public lastError ( void ) : array

public listCollections ([ array $options = array() ] ) : array

public prevError ( void ) : array

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

public resetError ( void ) : array

public selectCollection ( string $name ) : MongoCollection

public setProfilingLevel ( int $level ) : int

public setReadPreference ( string $read_preference [, array $tags ] ) : bool

public setSlaveOkay ([ bool $ok = TRUE ] ) : bool

public setWriteConcern ( mixed $w [, int $wtimeout ] ) : bool

public __toString ( void ) : string

}

Predefined Constants

MongoDB Log Levels

MongoDB::PROFILING_OFF: Profiling is off.
MongoDB::PROFILING_SLOW: Profiling is on for slow operations (>100 ms).
MongoDB::PROFILING_ON: 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 need to adjust the acknowledgement level (MongoCollection::insert(), MongoCollection::update(), MongoCollection::remove(), MongoCollection::save(), and MongoCollection::ensureIndex() all support this option). With the default value (1), an acknowledged operation will return once the database server has the operation. If the server goes down before the operation has been replicated to a secondary, it is possible to lose the operation forever. Thus, you can specify w to be higher than one and guarantee that at least one secondary has the operation before it is considered successful.

For example, if w is 2, the primary and one secondary 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 secondaries + primary, but then if one secondary is down the operation will fail and an exception will be thrown, so usually w=2 is safest (primary and one secondary).

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.

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 [deprecated]
MongoDB::forceError — Creates a database error
MongoDB::__get — Gets a collection
MongoDB::getCollectionInfo — Returns information about collections in this database
MongoDB::getCollectionNames — Gets an array of names for all collections in this database
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::getReadPreference — Get the read preference for this database
MongoDB::getSlaveOkay — Get slaveOkay setting for this database
MongoDB::getWriteConcern — Get the write concern for this database
MongoDB::lastError — Check if there was an error on the most recent db operation performed
MongoDB::listCollections — Gets an array of MongoCollection objects for all 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::setReadPreference — Set the read preference for this database
MongoDB::setSlaveOkay — Change slaveOkay setting for this database
MongoDB::setWriteConcern — Set the write concern for this database
MongoDB::__toString — The name of this database

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User Contributed Notes 3 notes

down

jeromakay at yahoo dot com ¶

13 years ago


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

down

-1

careddumattia at gmail dot com ¶

8 years ago


mongo extension is deprecated.

pecl install mongodb

down

-44

m dot espositoii at yahoo dot com ¶

12 years ago


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.

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The MongoDB class

Introduction

Class synopsis

Predefined Constants

MongoDB Log Levels

Fields

See Also

Table of Contents

User Contributed Notes 3 notes