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MongoDB\\Client::selectDatabase()
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.. default-domain:: mongodb

.. contents:: On this page
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Definition
----------

.. phpmethod:: MongoDB\\Client::selectDatabase()

   Selects a database on the server.

   .. code-block:: php

      function selectDatabase($databaseName, array $options = []): MongoDB\Database

   This method has the following parameters:

   .. include:: /includes/apiargs/MongoDBClient-method-selectDatabase-param.rst

   The ``$options`` parameter supports the following options:

   .. include:: /includes/apiargs/MongoDBClient-method-selectDatabase-option.rst

Return Values
-------------

A :phpclass:`MongoDB\\Database` object.

Errors/Exceptions
-----------------

.. include:: /includes/extracts/error-invalidargumentexception.rst

Behavior
--------

The selected database inherits options such as read preference and type mapping
from the :phpclass:`Client <MongoDB\\Client>` object. Options may be overridden
via the ``$options`` parameter.

Example
-------

The following example selects the ``test`` database:

.. code-block:: php

   <?php

   $client = new MongoDB\Client;

   $db = $client->selectDatabase('test');

The following examples selects the ``test`` database with a custom read
preference:

.. code-block:: php

   <?php

   $client = new MongoDB\Client;

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

See Also
--------

- :phpmethod:`MongoDB\\Client::__get()`
- :phpmethod:`MongoDB\\Database::__construct()`
