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MongoDB\Client::selectCollection()

Definition

MongoDB\Client::selectCollection

Selects a collection on the server.

function selectCollection(string $databaseName, string $collectionName, array $options = []): MongoDB\Collection

This method has the following parameters:

Parameter Type Description
$databaseName string The name of the database containing the collection to select.
$collectionName string The name of the collection to select.
$options array Optional. An array specifying the desired options.

The $options parameter supports the following options:

Option Type Description
readConcern MongoDB\Driver\ReadConcern Optional. The default read concern to use for collection operations. Defaults to the client’s read concern.
readPreference MongoDB\Driver\ReadPreference Optional. The default read preference to use for collection operations. Defaults to the client’s read preference.
typeMap array Optional. The type map to apply to cursors, which determines how BSON documents are converted to PHP values. Defaults to the client’s type map.
writeConcern MongoDB\Driver\WriteConcern Optional. The default write concern to use for collection operations. Defaults to the client’s write concern.

Return Values

A MongoDB\Collection object.

Errors/Exceptions

MongoDB\Exception\InvalidArgumentException for errors related to the parsing of parameters or options.

Behavior

The selected collection inherits options such as read preference and type mapping from the Client object. Options may be overridden via the $options parameter.

Example

The following example selects the users collection in the test database:

<?php

$client = new MongoDB\Client;

$collection = $client->selectCollection('test', 'users');

The following example selects the users collection in the test database with a custom read preference:

<?php

$client = new MongoDB\Client;

$collection = $client->selectCollection(
    'test',
    'users',
    [
        'readPreference' => new MongoDB\Driver\ReadPreference(MongoDB\Driver\ReadPreference::RP_SECONDARY),
    ]
);