MongoDBDatabase__construct.txt

================================
MongoDB\\Database::__construct()
================================


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Definition
----------

.. phpmethod:: MongoDB\Database::__construct()

   Constructs a new :phpclass:`Database <MongoDB\Database>` instance.

   .. code-block:: php

      function __construct(
          MongoDB\Driver\Manager $manager,
          string $databaseName,
          array $options = []
      )

Parameters
----------

``$manager`` : :php:`MongoDB\Driver\Manager <class.mongodb-driver-manager>`
  The :php:`Manager <mongodb-driver-manager>` instance from the extension. The
  manager maintains connections between the driver and MongoDB.

``$databaseName`` : string
  The name of the database.

``$options`` : array
  An array specifying the desired options.

  .. list-table::
     :header-rows: 1
     :widths: 20 20 80

     * - Name
       - Type
       - Description

     * - builderEncoder
       - MongoDB\\Codec\\Encoder
       - Encoder to use for query and aggregation builders. If not set, this option
         defaults to a new instance of the ``MongoDB\Builder\BuilderEncoder`` class.

         .. versionadded:: 1.21

     * - readConcern
       - :php:`MongoDB\Driver\ReadConcern <class.mongodb-driver-readconcern>`
       - The default read concern to use for database operations. Defaults to
         the manager's read concern.

     * - readPreference
       - :php:`MongoDB\Driver\ReadPreference <class.mongodb-driver-readpreference>`
       - The default read preference to use for database operations. Defaults to
         the manager's read preference.

     * - typeMap
       - array
       - Default :php:`type map
         <manual/en/mongodb.persistence.deserialization.php#mongodb.persistence.typemaps>`
         to apply to cursors, which determines how BSON documents are converted
         to PHP values. The library uses the following type map by default:

         .. code-block:: php

            [
                'array' => 'MongoDB\Model\BSONArray',
                'document' => 'MongoDB\Model\BSONDocument',
                'root' => 'MongoDB\Model\BSONDocument',
            ]

     * - writeConcern
       - :php:`MongoDB\Driver\WriteConcern <class.mongodb-driver-writeconcern>`
       - The default write concern to use for database operations. Defaults to
         the manager's write concern.

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

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

Behavior
--------

If you construct a Database explicitly, the Database inherits any options from
the :php:`MongoDB\Driver\Manager <class.mongodb-driver-manager>` object. If
you select the Database from a :phpclass:`Client <MongoDB\Client>` object, the
Database inherits its options from that object.

See Also
--------

- :phpmethod:`MongoDB\Database::withOptions()`
- :phpmethod:`MongoDB\Client::getDatabase()`
- :phpmethod:`MongoDB\Client::__get()`