db.collection.createIndexes.txt

=============================
db.collection.createIndexes()
=============================

.. default-domain:: mongodb

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

Definition
----------

.. method:: db.collection.createIndexes( [ keyPatterns ], options, commitQuorum )


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


   Creates one or more indexes on a collection.

   :method:`db.collection.createIndexes()` takes the following
   parameters:

   .. list-table::
      :header-rows: 1
      :widths: 20 20 80
   
      * - Parameter
   
        - Type
   
        - Description
   
      * - ``keyPatterns``
   
        - document
   
        - .. _key_patterns:
        
          An array containing index specification documents. Each document
          contains field and value pairs where the field is
          the index key and the value describes the type of index for that
          field. For an ascending index on a field, specify a value of ``1``; for
          descending index, specify a value of ``-1``.
          
          
          
          MongoDB supports several different index types including
          :ref:`text <index-feature-text>`, :ref:`geospatial
          <index-feature-geospatial>`, and :ref:`hashed
          <index-type-hashed>` indexes. See :ref:`index types <index-types>`
          for more information.
          
          .. versionchanged:: 4.2
          
             MongoDB 4.2 :ref:`wildcard indexes <wildcard-index-core>`
             support workloads where users query against custom fields or a
             large variety of fields in a collection:
          
             - To create a wildcard index on all fields and subfields in a 
               document, specify ``{ "$**" : 1 }`` as the index key. You
               cannot specify a descending index key when creating a wildcard
               index.
          
               You can also either include *or* exclude specific fields and
               their subfields from the index using the optional
               ``wildcardProjection`` parameter.
          
               .. include:: /includes/extracts/wildcard-index-id.rst
          
             - You can create a wildcard index on a specific field
               and its subpaths by specifying the full path to that field as the
               index key and append ``"$**"`` to the path:
          
               ``{ "path.to.field.$**" : 1 }`` 
          
               You cannot specify a descending index key when creating a
               wildcard index.
          
               The path-specific wildcard index syntax is incompatible with the
               ``wildcardProjection`` option. You cannot specify additional
               inclusions or exclusions on the specified path.
          
             The wildcard index key **must** use one of the syntaxes listed
             above. For example, you cannot specify a
             :doc:`compound index key </core/index-compound>`.  For more 
             complete documentation on wildcard indexes, including restrictions 
             on their creation, see :ref:`wildcard-index-restrictions`.
          
             .. include:: /includes/extracts/wildcard-index-fcv.rst
          
          
          
          For more information on creating wildcard indexes, see
          :ref:`createIndexes-method-wildcard-behavior`.
          
          
          
   
      * - ``options``
   
        - document
   
        - Optional. A document that contains a set of options that controls the creation
          of the indexes. See :ref:`createIndexes-method-options` for details.
          
      * - :ref:`commitQuorum <createIndexes-method-commitQuorum>`

        - integer or string

        - .. _createIndexes-method-commitQuorum:
        
          Optional. The minimum number of data-bearing voting replica
          set members (i.e. commit quorum), including the primary, that
          must report a successful :ref:`index build
          <index-operations-replicated-build>` before the primary
          marks the ``indexes`` as ready. A "voting" member is any
          replica set member where :rsconf:`members[n].votes` is greater
          than ``0``.
          
          Supports the following values:

          - ``"votingMembers"`` - all data-bearing voting replica set
            members (*Default*).

          - ``"majority"`` - a simple majority of data-bearing voting
            replica set members.

          - ``<int>`` - a specific number of data-bearing voting 
            replica set members.

          - ``0`` - Disables quorum-voting behavior. Members 
            start the index build simultaneously but do *not* 
            vote or wait for quorum before completing the 
            index build. If you start an index build with 
            a commit quorum of ``0``, you cannot later modify the 
            commit quorum using :dbcommand:`setIndexCommitQuorum`.

          - A replica set :doc:`tag name
            </tutorial/configure-replica-set-tag-sets>`.

          .. versionadded:: 4.4


   The :method:`db.collection.createIndexes()` is a wrapper around the
   :dbcommand:`createIndexes` command.

   To minimize the impact of building an index on replica sets and sharded
   clusters, use a rolling index build procedure
   as described on :doc:`/tutorial/build-indexes-on-replica-sets`.

.. _createIndexes-method-options:

Options
-------

The ``options`` document contains a set of options that control the
creation of the indexes. Different index types can have additional
options specific for that type.

Multiple index options can be specified in the same document. However,
if you specify mutiple option documents the :method:`db.collection.createIndexes()`
operation will fail.

Consider the following :method:`db.collection.createIndexes()` operation:

.. code-block:: javascript

   db.collection.createIndexes(
      [
        {
          "a": 1
        },
        {
          "b": 1
        }
      ],
      {
        unique: true,
        sparse: true,
        expireAfterSeconds: 3600
      }
    )

If the options specification had been split into multiple documents
like this:
``{ unique: true }, { sparse: true, expireAfterSeconds: 3600 }``
the index creation operation would have failed.

.. important::

   When you specify options to
   :method:`db.collection.createIndexes()`, the options apply to
   *all* of the specified indexes. For example, if you specify a
   collation option, all of the created indexes will include that
   collation.
   
   :method:`db.collection.createIndexes()` will return an error if you
   attempt to create indexes with incompatible options or too many
   arguments. Refer to the option descriptions for more information.

Options for All Index Types
~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following options are available for all index types unless
otherwise specified:

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

   * - Parameter

     - Type

     - Description

   * - ``background``

     - boolean

     - Optional. *Deprecated in MongoDB 4.2.*
       
       .. include:: /includes/extracts/4.2-index-background.rst
       
       

   * - ``unique``

     - boolean

     - Optional. Specifies that each index specified in the ``keyPatterns`` array
       is a :doc:`unique index </core/index-unique>`. Unique indexes will not
       accept insertion or update of documents where the index key value matches an
       existing value in the index.
       
       
       Specify ``true`` to create a unique index. The
       default value is ``false``.
       
       The option is *unavailable* for :doc:`hashed </core/index-hashed>`
       indexes.
       
       
       

   * - ``name``

     - string

     - Optional. The name of the index. If unspecified, MongoDB generates an index name
       by concatenating the names of the indexed fields and the sort order.
       
       .. note:: Changed in MongoDB 4.2

       
          .. include:: /includes/extracts/4.2-changes-index-names.rst
       
       
       Options specified to :method:`db.collection.createIndexes` apply to **all** of the index
       specifications included in the key pattern array. Since index names
       must be unique, you may
       only specify name if you are creating a single index using
       :method:`db.collection.createIndexes`.
       
       

   * - ``partialFilterExpression``

     - document

     - .. _partialFilterExpression:
   
       Optional. If specified, the indexes only reference documents that match the
       filter expression. See :doc:`/core/index-partial` for more
       information.
       
       
       A filter expression can include:
       
       .. include:: /includes/fact-partial-filter-expression-operators.rst
       
       You can specify a ``partialFilterExpression`` option for all MongoDB
       :ref:`index types <index-types>`.
       
       .. versionadded:: 3.2
       
       
       

   * - ``sparse``

     - boolean

     - Optional. If ``true``, the indexes only reference documents with the specified
       fields. These indexes use less space but behave differently in some
       situations (particularly sorts). The default value is ``false``.
       See :doc:`/core/index-sparse` for more information.

       The following index types are sparse by default and ignore
       this option:

       - :doc:`2dsphere </core/2dsphere>`
       - :doc:`2d </core/2d>`
       - :doc:`geoHaystack </core/geohaystack>`
       - :doc:`text </core/index-text>`

       For a compound index that includes ``2dsphere`` index key(s)
       along with keys of other types, only the ``2dsphere`` index
       fields determine whether the index references a document.

       .. versionchanged:: 3.2 
       
          Starting in MongoDB 3.2, MongoDB provides the option to create
          :ref:`partial indexes <index-type-partial>`. Partial indexes
          offer a superset of the functionality of sparse indexes. If you
          are using MongoDB 3.2 or later, :ref:`partial indexes
          <index-type-partial>` should be preferred over sparse indexes.

   * - ``expireAfterSeconds``

     - integer

     - Optional. Specifies a value, in seconds, as a :term:`TTL` to control how long
       MongoDB retains documents in this collection. See
       :doc:`/tutorial/expire-data` for more information on this
       functionality. This applies only to :term:`TTL` indexes.
       
       
   * - :ref:`hidden <method-createIndexes-hidden>`

     - boolean

     - .. _method-createIndexes-hidden:

       Optional. A flag that determines whether the index is
       :doc:`hidden </core/index-hidden>` from the query planner. A
       hidden index is not evaluated as part of the query plan
       selection.

       Default is ``false``.

       To use the ``hidden`` option, you must have
       :ref:`featureCompatibilityVersion <view-fcv>` set to ``4.4`` or
       greater. However, once hidden, the index remains hidden even
       with :ref:`featureCompatibilityVersion <view-fcv>` set to
       ``4.2`` on MongoDB 4.4 binaries.

       .. versionadded:: 4.4

   * - ``storageEngine``

     - document

     - Optional. Allows users to configure the storage engine for the created
       indexes.
       
       
       The ``storageEngine`` option should take the following form:
       
       .. code-block:: javascript
       
          storageEngine: { <storage-engine-name>: <options> }
       
       Storage engine configuration options specified when creating indexes are
       validated and logged to the :term:`oplog` during replication to
       support replica sets with members that use different storage
       engines.


.. _create-indexes-collation:

Option for Collation
~~~~~~~~~~~~~~~~~~~~


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

   * - Parameter

     - Type

     - Description

   * - ``collation``

     - document

     - Optional. Specifies the :ref:`collation <collation>` for the index.
       
       .. include:: /includes/extracts/collation-description.rst
       
       .. include:: /includes/extracts/collation-index-collection.rst
       
       .. include:: /includes/extracts/collation-option-specification.rst
       
       .. versionadded:: 3.4
       
       



.. include:: /includes/extracts/collation-index-type-restrictions.rst

.. include:: /includes/extracts/collation-index-type-restrictions-addendum.rst

Collation and Index Use
```````````````````````

.. include:: /includes/extracts/collation-index.rst

Options for ``text`` Indexes
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following options are available for :doc:`text </core/index-text>`
indexes only:


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

   * - Parameter

     - Type

     - Description

   * - ``weights``

     - document

     - Optional. For :doc:`text </core/index-text>` indexes, a document that contains
       field and weight pairs. The weight is an integer ranging from 1 to
       99,999 and denotes the significance of the field relative to the
       other indexed fields in terms of the score. You can specify weights
       for some or all the indexed fields. See
       :doc:`/tutorial/control-results-of-text-search` to adjust the scores.
       The default value is ``1``.

       Starting in MongoDB 5.0, the :ref:`weights <specify-weights>` 
       option is only allowed for text indexes.

   * - ``default_language``

     - string

     - Optional. For :doc:`text </core/index-text>` indexes, the language that
       determines the list of stop words and the rules for the stemmer and
       tokenizer. See :ref:`text-search-languages` for the available
       languages and :doc:`/tutorial/specify-language-for-text-index` for
       more information and examples. The default value is ``english``.
       
       

   * - ``language_override``

     - string

     - Optional. For :doc:`text </core/index-text>` indexes, the name of the field, in
       the collection's documents, that contains the override language for
       the document. The default value is ``language``. See
       :ref:`specify-language-field-text-index-example` for an example.
       
       

   * - ``textIndexVersion``

     - integer

     - Optional. The ``text`` index version number. Users can use this option to
       override the default version number.
       
       For available versions, see :ref:`text-versions`.


Options for ``2dsphere`` Indexes
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following option is available for :doc:`2dsphere </core/2dsphere>`
indexes only:


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

   * - Parameter

     - Type

     - Description

   * - ``2dsphereIndexVersion``

     - integer

     - Optional. The ``2dsphere`` index version number. Users can use this option to
       override the default version number.
       
       For the available versions, see :ref:`2dsphere-v2`.


Options for ``2d`` Indexes
~~~~~~~~~~~~~~~~~~~~~~~~~~

The following options are available for :doc:`2d </core/2d>` indexes
only:


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

   * - Parameter

     - Type

     - Description

   * - ``bits``

     - integer

     - Optional. For :doc:`2d </core/2d>` indexes, the number of precision of the
       stored :term:`geohash` value of the location data.
       
       The ``bits`` value ranges from 1 to 32 inclusive. The default value
       is ``26``.
       
       

   * - ``min``

     - number

     - Optional. For :doc:`2d </core/2d>` indexes, the lower inclusive boundary for
       the longitude and latitude values. The default value is ``-180.0``.
       
       

   * - ``max``

     - number

     - Optional. For :doc:`2d </core/2d>` indexes, the upper inclusive boundary for
       the longitude and latitude values. The default value is ``180.0``.
       
       



Options for ``geoHaystack`` Indexes
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following option is available for :doc:`geoHaystack </core/geohaystack>`
indexes only:


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

   * - Parameter

     - Type

     - Description

   * - ``bucketSize``

     - number

     - For :doc:`geoHaystack </core/geohaystack>` indexes, specify the
       number of units within which to group the location values; i.e. group
       in the same bucket those location values that are within the
       specified number of units to each other.
       
       The value must be greater than 0.

.. note:: Removed in MongoDB 5.0

   .. include:: /includes/fact-5.0-geohaystack-removed.rst

.. _createIndexes-method-wildcard-option:

Options for ``wildcard`` indexes
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following option is available for
:ref:`wildcard <wildcard-index-core>` indexes only:

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

   * - Parameter

     - Type

     - Description

   * - ``wildcardProjection``

     - document

     - Optional. Allows users to include or exclude specific field paths from
       the  :ref:`wildcard index <wildcard-index-core>`. This option is only 
       valid if creating a :ref:`wildcard index <wildcard-index-core>`.
       
       
       
       The ``wildcardProjection`` option takes the following form:
       
       .. code-block:: javascript
       
          wildcardProjection: {
            "path.to.field.a" : <value>,
            "path.to.field.b" : <value>
          }
       
       The ``<value>`` can be either of the following:
       
       - ``1`` or ``true`` to include the field in the wildcard index.
       
       - ``0`` or ``false`` to exclude the field from the wildcard index. 
       
       .. include:: /includes/extracts/wildcard-index-id.rst
       
       Options specified to :method:`db.collection.createIndexes` apply to **all** of the index
       specifications included in the key pattern array. Specify 
       ``wildcardProjection`` only if you are creating a single wildcard index using 
       :method:`db.collection.createIndexes`.
       
       



Behaviors
---------

Concurrency
~~~~~~~~~~~

.. versionchanged:: 4.2

.. include:: /includes/extracts/createIndexes-method-resource-lock.rst

Recreating an Existing Index
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If you call :method:`db.collection.createIndexes()` for an index or
indexes that already exist, MongoDB does not recreate the existing
index or indexes.

Index Options
~~~~~~~~~~~~~

Non-Collation and Non-Hidden Options
````````````````````````````````````

With the exception of the :ref:`collation option
<method-createIndexes-collation-option>`, if you create an index with one
set of index options and then try to recreate the same index but with
different index options, MongoDB will not change the options nor
recreate the index.

The :ref:`hidden <createIndexes-hidden-option>` option can be changed
without dropping and recreating the index. See
:ref:`method-createIndexes-hidden-option`.

To change the other index options, drop the existing index with
:method:`db.collection.dropIndex()` before running
:method:`db.collection.createIndexes()` with the new options.

.. _method-createIndexes-collation-option:

Collation Option
````````````````

.. include:: /includes/extracts/collation-index-options.rst

.. _method-createIndexes-hidden-option:

Hidden Option
``````````````

.. versionadded:: 4.4

.. note::

   To hide an index, you must have :ref:`featureCompatibilityVersion
   <view-fcv>` set to ``4.4`` or greater. However, once hidden, the
   index remains hidden even with :ref:`featureCompatibilityVersion
   <view-fcv>` set to ``4.2`` on MongoDB 4.4 binaries.

To hide or unhide existing indexes, you can use the following
:binary:`~bin.mongosh` methods:

- :method:`db.collection.hideIndex()`

- :method:`db.collection.unhideIndex()`

For example,

- To change the ``hidden`` option for an index to ``true``, use the
  :method:`db.collection.hideIndex()` method:

  .. code-block:: javascript

     db.restaurants.hideIndex( { borough: 1, ratings: 1 } );

- To change the ``hidden`` option for an index to ``false``, use the
  :method:`db.collection.unhideIndex()` method:

  .. code-block:: javascript

     db.restaurants.unhideIndex( { borough: 1, city: 1 } );

.. seealso::

   :doc:`/core/index-hidden`

Index Key Length Limit
~~~~~~~~~~~~~~~~~~~~~~

For MongoDB 2.6 through MongoDB versions with
:ref:`featureCompatibilityVersion <view-fcv>` (fCV) set to ``"4.0"`` or
earlier, MongoDB will **not** create an index on a collection if the
index entry for an existing document exceeds the |limit|.

.. |limit| replace:: :limit:`Maximum Index Key Length <Index Key Limit>`

.. _createIndexes-method-wildcard-behavior:

Wildcard Indexes
~~~~~~~~~~~~~~~~

.. versionadded:: 4.2

- .. include:: /includes/extracts/wildcard-index-id.rst

- .. include:: /includes/extracts/wildcard-index-fcv.rst

- .. include:: /includes/extracts/wildcard-index-restrictions.rst

  For complete documentation on wildcard index restrictions, see 
  :ref:`wildcard-index-restrictions`.

For examples of wildcard index creation, see
:ref:`createIndexes-method-wildcard-examples`. For complete 
documentation on Wildcard Indexes, see :ref:`wildcard-index-core`.

Transactions
~~~~~~~~~~~~

.. versionchanged:: 4.4

.. include:: /includes/extracts/transactions-explicit-ddl.rst

.. |operation| replace:: :method:`db.collection.createIndexes()`


Example
-------

.. seealso::

   :method:`db.collection.createIndex()` for examples of various index
   specifications.

Create Indexes Without Options
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Consider a ``restaurants`` collection containing documents that
resemble the following:

.. code-block:: javascript

   {
      location: {
         type: "Point",
         coordinates: [-73.856077, 40.848447]
      },
      name: "Morris Park Bake Shop",
      cuisine: "Cafe",
      borough: "Bronx",
   }

The following example creates two indexes on the ``restaurants``
collection: an ascending index on the ``borough`` field and a
:doc:`2dsphere </core/2dsphere>` index on the ``location`` field.

.. code-block:: bash

   db.restaurants.createIndexes([{"borough": 1}, {"location": "2dsphere"}])

Create Indexes with Collation Specified
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following example creates two indexes on the ``products``
collection: an ascending index on the ``manufacturer`` field and an
ascending index on the ``category`` field. Both indexes use a :ref:`collation
<create-index-collation>` that specifies the locale ``fr`` and
comparison strength ``2``:

.. code-block:: javascript

   db.products.createIndexes( [ { "manufacturer": 1}, { "category": 1 } ],
      { collation: { locale: "fr", strength: 2 } })

For queries or sort operations on the indexed keys that uses the same collation
rules, MongoDB can use the index. For details, see :ref:`createIndex-collation-index-use`.

.. _createIndexes-method-wildcard-examples:

Create a Wildcard Index
~~~~~~~~~~~~~~~~~~~~~~~

.. versionadded:: 4.2

   .. include:: /includes/extracts/wildcard-index-fcv.rst

   For complete documentation on Wildcard Indexes, see
   :ref:`wildcard-index-core`.

The following lists examples of wildcard index creation:

- :ref:`createIndexes-method-onepath`
- :ref:`createIndexes-method-allpaths`
- :ref:`createIndexes-method-inclusion`
- :ref:`createIndexes-method-exclusion`

.. _createIndexes-method-onepath:

Create a Wildcard Index on a Single Field Path
``````````````````````````````````````````````

.. include:: /includes/extracts/wildcard-index-example-pre.rst

The following operation creates a wildcard index on the 
``product_attributes`` field:

.. code-block:: bash

   use inventory
   db.products_catalog.createIndexes( 
     [ { "product_attributes.$**" : 1 } ] 
   )

With this wildcard index, MongoDB indexes all scalar values of
``product_attributes``. If the field is a nested document or array, the
wildcard index recurses into the document/array and indexes all scalar
fields in the document/array.

The wildcard index can support arbitrary single-field queries on 
``product_attributes`` or one of its nested fields:

.. code-block:: bash

   db.products_catalog.find( { "product_attributes.superFlight" : true } )
   db.products_catalog.find( { "product_attributes.maxSpeed" : { $gt : 20 } } )
   db.products_catalog.find( { "product_attributes.elements" : { $eq: "water" } } )

.. |projection-ref| replace:: :ref:`parameter documentation <createIndexes-method-wildcard-option>`

.. note::

   The path-specific wildcard index syntax is incompatible with the
   ``wildcardProjection`` option. See the |projection-ref| for more
   information.


.. _createIndexes-method-allpaths:

Create a Wildcard Index on All Field Paths
``````````````````````````````````````````

.. include:: /includes/extracts/wildcard-index-example-pre.rst

The following operation creates a wildcard index on all scalar fields
(excluding the ``_id`` field):

.. code-block:: bash

   use inventory
   db.products_catalog.createIndexes(
     [ { "$**" : 1 } ]
   )

With this wildcard index, MongoDB indexes all scalar fields for each
document in the collection. If a given field is a nested document or
array, the wildcard index recurses into the document/array and indexes
all scalar fields in the document/array.

The created index can support queries on any arbitrary field 
within documents in the collection:

.. code-block:: bash

   db.products_catalog.find( { "product_price" : { $lt : 25 } } )
   db.products_catalog.find( { "product_attributes.elements" : { $eq: "water" } } )

.. note::

   Wildcard indexes omit the ``_id`` field by default. To include the
   ``_id`` field in the wildcard index, you must explicitly include it
   in the ``wildcardProjection`` document. See |projection-ref| for
   more information.

.. _createIndexes-method-inclusion:

Create a Wildcard Index on Multiple Specific Field Paths
````````````````````````````````````````````````````````

.. include:: /includes/extracts/wildcard-index-example-pre.rst

The following operation creates a wildcard index and uses
the ``wildcardProjection`` option to include only scalar values of the
``product_attributes.elements`` and ``product_attributes.resistance``
fields in the index. 

.. code-block:: bash

   use inventory
   db.products_catalog.createIndexes(
     [ { "$**" : 1 } ],
     {
       "wildcardProjection" : {
         "product_attributes.elements" : 1,
         "product_attributes.resistance" : 1
       }
     }
   )

While the key pattern ``"$**"`` covers all fields in the document, the
``wildcardProjection`` field limits the index to only the included
fields. For complete documentation on ``wildcardProjection``, see 
:ref:`createIndexes-method-wildcard-option`.

If a field is a nested document or array, the wildcard
index recurses into the document/array and indexes all scalar fields in 
the document/array.

The created index can support queries on any scalar field
included in the ``wildcardProjection``:

.. code-block:: bash

   db.products_catalog.find( { "product_attributes.elements" : { $eq: "Water" } } )
   db.products_catalog.find( { "product_attributes.resistance" : "Bludgeoning" } )

.. note::

   .. include:: /includes/extracts/wildcard-index-inclusion-exclusion.rst

.. _createIndexes-method-exclusion:

Create a Wildcard Index that Excludes Multiple Specific Field Paths
```````````````````````````````````````````````````````````````````

.. include:: /includes/extracts/wildcard-index-example-pre.rst

The following operation creates a wildcard index and uses
the ``wildcardProjection`` document to index all scalar fields
for each document in the collection, *excluding* the 
``product_attributes.elements`` and ``product_attributes.resistance``
fields:

.. code-block:: bash

   use inventory
   db.products_catalog.createIndexes(
     [ { "$**" : 1 } ],
     {
       "wildcardProjection" : {
         "product_attributes.elements" : 0,
         "product_attributes.resistance" : 0
       }
     }
   )

While the key pattern ``"$**"`` covers all fields in the document, the
``wildcardProjection`` field excludes the specified fields from the
index. For complete documentation on ``wildcardProjection``, see 
:ref:`createIndexes-method-wildcard-option`.

If a field is a nested document or array, the wildcard
index recurses into the document/array and indexes all scalar fields in 
the document/array.

The created index can support queries on any scalar field **except**
those excluded by ``wildcardProjection``:

.. code-block:: bash

   db.products_catalog.find( { "product_attributes.maxSpeed" : { $gt: 25 } } )
   db.products_catalog.find( { "product_attributes.superStrength" : true } )

.. note::

   .. include:: /includes/extracts/wildcard-index-inclusion-exclusion.rst

Create Indexes With Commit Quorum
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. include:: /includes/extracts/4.4-changes-index-builds-simultaneous-fcv.rst

.. include:: /includes/extracts/4.4-changes-index-builds-simultaneous.rst

Specify the :ref:`commitQuorum <createIndexes-method-commitQuorum>`
parameter to the :method:`~db.collection.createIndexes` operation to set
the minimum number of data-bearing voting members (i.e commit
quorum), including the primary, which must complete the index build
before the primary marks the indexes as ready. The default commit quorum
is ``votingMembers``, or all data-bearing voting replica set members.

The following operation creates an index with a :ref:`commit quorum
<createIndexes-method-commitQuorum>` of ``"majority"``:

.. code-block:: javascript

   db.getSiblingDB("examples").invoices.createIndexes(
     { "invoices" : 1 },
     { },
     "majority"
   )

The :term:`primary` marks index build as ready only after a simple
majority of data-bearing voting members "vote" to commit the index
build. For more information on index builds and the voting process, see
:ref:`index-operations-replicated-build`.

Additional Information
----------------------

For additional information about indexes, refer to:

- The :doc:`/indexes` section of this manual for full
  documentation of indexes and indexing in MongoDB.

- :method:`db.collection.getIndexes()` to view the specifications of
  existing indexes for a collection.

- :doc:`/core/index-text` for details on creating ``text``
  indexes.

- :ref:`index-feature-geospatial` for geospatial queries.

- :ref:`index-feature-ttl` for expiration of data.