cursor.readConcern.txt

====================
cursor.readConcern()
====================

.. default-domain:: mongodb

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

.. method:: cursor.readConcern(level)


   .. include:: /includes/fact-mongosh-shell-method.rst

   Specify a :term:`read concern` for the :method:`db.collection.find()`
   method.

   The :method:`~cursor.readConcern()` method has the following form:

   .. code-block:: javascript

      db.collection.find().readConcern(<level>)

   The :method:`~cursor.readConcern()` method has the following
   parameter:


   .. list-table::
      :header-rows: 1
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      * - Parameter
   
        - Type
   
        - Description
   
      * - ``level``
   
        - string
   
        - :term:`Read concern <read concern>` level.
          
          .. include:: /includes/fact-readConcern-option-description.rst
          
          
Compatibility
-------------

This method is available in deployments hosted in the following environments: 

.. include:: /includes/fact-environments-atlas-only.rst

.. include:: /includes/fact-environments-atlas-support-all.rst

.. include:: /includes/fact-environments-onprem-only.rst   


Considerations
--------------

Read Your Own Writes
~~~~~~~~~~~~~~~~~~~~~

.. include:: /includes/fact-read-own-writes.rst

Linearizable Read Concern Performance
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. include:: /includes/extracts/maxTimeMS-readConcern-cursor.rst

.. code-block:: javascript

   db.restaurants.find( { _id: 5 } ).readConcern("linearizable").maxTimeMS(10000)


.. seealso::

   :doc:`/reference/read-concern`