db.collection.deleteMany.txt

==========================
db.collection.deleteMany()
==========================

.. default-domain:: mongodb

.. contents:: On this page
   :local:
   :backlinks: none
   :depth: 1
   :class: singlecol

Definition
----------

.. method:: db.collection.deleteMany()

   Removes all documents that match the ``filter`` from a collection.

   .. code-block:: javascript

      db.collection.deleteMany(
         <filter>,
         {
            writeConcern: <document>
         }
      )


   .. list-table::
      :header-rows: 1
      :widths: 20 20 80
   
      * - Parameter
   
        - Type
   
        - Description
   
      * - ``filter``
   
        - document
   
        - Specifies deletion criteria using :doc:`query operators
          </reference/operator>`. 
          
          To delete all documents in a collection, pass in an empty document (``{ }``).
          
          
   
      * - ``writeConcern``
   
        - document
   
        - Optional. A document expressing the :doc:`write concern
          </reference/write-concern>`. Omit to use the default write concern.
          
          
   


   :returns:
      
     A document containing:
      
      - A boolean ``acknowledged`` as ``true`` if the operation ran with 
        :term:`write concern` or ``false`` if write concern was disabled
		
     - ``deletedCount`` containing the number of deleted documents

Behavior
--------

.. _deleteMany-capped-collection:

Capped Collections
~~~~~~~~~~~~~~~~~~

:method:`~db.collection.deleteMany()` throws a ``WriteError`` exception 
if used on a :term:`capped collection`. To remove all documents from a capped 
collection, use :method:`db.collection.drop()` instead.

.. _deleteMany-delete-multiple-documents:

Delete a Single Document
~~~~~~~~~~~~~~~~~~~~~~~~

To delete a single document, use :method:`db.collection.deleteOne()` instead. 

Alternatively, use a field that is a part of a :term:`unique index` such as 
``_id``. 

Examples
--------

.. _deleteMany-example-delete-multiple-document:

Delete Multiple Documents
~~~~~~~~~~~~~~~~~~~~~~~~~

The ``orders`` collection has documents with the following structure:

.. code-block:: javascript

   {
      _id: ObjectId("563237a41a4d68582c2509da"),
      stock: "Brent Crude Futures",
      qty: 250,
      type: "buy-limit",
      limit: 48.90,
      creationts: ISODate("2015-11-01T12:30:15Z"),
      expiryts: ISODate("2015-11-01T12:35:15Z"),
      client: "Crude Traders Inc."
   }
   
The following operation deletes all documents where ``client : "Crude Traders 
Inc."``:

.. code-block:: javascript

   try {
      db.orders.deleteMany( { "client" : "Crude Traders Inc." } );
   } catch (e) {
      print (e);
   }
   
The operation returns:

.. code-block:: javascript

   { "acknowledged" : true, "deletedCount" : 10 }
   
The following operation deletes all documents where ``stock : "Brent Crude 
Futures"`` and ``limit`` is greater than ``48.88``:

.. code-block:: javascript

   try {
      db.orders.deleteMany( { "stock" : "Brent Crude Futures", "limit" : { $gt : 48.88 } } );
   } catch (e) {
      print (e);
   }

The operation returns:

.. code-block:: javascript

   { "acknowledged" : true, "deletedCount" : 8 }

.. _deleteMany-example-update-with-write-concern:

deleteMany() with Write Concern
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Given a three member replica set, the following operation specifies a 
``w`` of ``majority`` and ``wtimeout`` of ``100``:

.. code-block:: javascript

   try {
      db.orders.deleteMany(
          { "client" : "Crude Traders Inc." },
          { w : "majority", wtimeout : 100 }
      );
   } catch (e) {
      print (e);
   }

If the acknowledgement takes longer than the ``wtimeout`` limit, the following 
exception is thrown:

.. code-block:: javascript

   WriteConcernError({
      "code" : 64,
      "errInfo" : {
         "wtimeout" : true
      },
      "errmsg" : "waiting for replication timed out"
   })