collection – Collection level operations — PyMongo 2.5 documentation

### Navigation

- index
- modules |
- next |
- previous |
- PyMongo 2.5 documentation »
- API Documentation »
- `pymongo` – Python driver for MongoDB »

# `collection` – Collection level operations

Collection level utilities for Mongo.

`pymongo.``ASCENDING` = 1

  Ascending sort order.

`pymongo.``DESCENDING` = -1

  Descending sort order.

`pymongo.``GEO2D` = '2d'

  Index specifier for a 2-dimensional geospatial index.

  New in version 1.5.1.

  Note

  Geo-spatial indexing requires server version >= 1.3.3.

`pymongo.``GEOHAYSTACK` = 'geoHaystack'

  Index specifier for a 2-dimensional haystack index.

  New in version 2.1.

  Note

  Geo-spatial indexing requires server version >= 1.5.6.

`pymongo.``GEOSPHERE` = '2dsphere'

  Index specifier for a spherical geospatial index.

  New in version 2.5.

  Note

  2dsphere indexing requires server version >= 2.4.0.

`pymongo.``HASHED` = 'hashed'

  Index specifier for a hashed index.

  New in version 2.5.

  Note

  hashed indexing requires server version >= 2.4.0.

class `pymongo.collection.``Collection`(database, name[, create=False[, **kwargs]]])

  Get / create a Mongo collection.

  Raises `TypeError` if name is not an instance of `basestring` (`str` in python 3). Raises `InvalidName` if name is not a valid collection name. Any additional keyword arguments will be used as options passed to the create command. See `create_collection()` for valid options.

  If create is `True` or additional keyword arguments are present a create command will be sent. Otherwise, a create command will not be sent and the collection will be created implicitly on first use.

  Parameters : | database: the database to get a collection from name: the name of the collection to get create (optional): if `True`, force collection creation even without options being set **kwargs (optional): additional keyword arguments will be passed as options for the create collection command

  Changed in version 2.2: Removed deprecated argument: options

  New in version 2.1: uuid_subtype attribute

  Changed in version 1.5: deprecating options in favor of kwargs

  New in version 1.5: the create parameter

  See general MongoDB documentation

  collections

  `c[name] || c.name`

    Get the name sub-collection of `Collection` c.

    Raises `InvalidName` if an invalid collection name is used.

  `full_name`

    The full name of this `Collection`.

    The full name is of the form database_name.collection_name.

    Changed in version 1.3: `full_name` is now a property rather than a method.

  `name`

    The name of this `Collection`.

    Changed in version 1.3: `name` is now a property rather than a method.

  `database`

    The `Database` that this `Collection` is a part of.

    Changed in version 1.3: `database` is now a property rather than a method.

  `read_preference`

    The read preference mode for this instance.

    See `ReadPreference` for available options.

    New in version 2.1.

  `tag_sets`

    Set `tag_sets` to a list of dictionaries like [{‘dc’: ‘ny’}] to read only from members whose `dc` tag has the value `"ny"`. To specify a priority-order for tag sets, provide a list of tag sets: `[{'dc': 'ny'}, {'dc': 'la'}, {}]`. A final, empty tag set, `{}`, means “read from any member that matches the mode, ignoring tags.” ReplicaSetConnection tries each set of tags in turn until it finds a set of tags with at least one matching member.

    > See also

    > Data-Center Awareness

    New in version 2.3.

  `secondary_acceptable_latency_ms`

    Any replica-set member whose ping time is within secondary_acceptable_latency_ms of the nearest member may accept reads. Defaults to 15 milliseconds.

    See `ReadPreference`.

    New in version 2.3.

    Note

    `secondary_acceptable_latency_ms` is ignored when talking to a replica set through a mongos. The equivalent is the localThreshold command line option.

  `write_concern`

    The default write concern for this instance.

    Supports dict style access for getting/setting write concern options. Valid options include:

    - w: (integer or string) If this is a replica set, write operations will block until they have been replicated to the specified number or tagged set of servers. w=<int> always includes the replica set primary (e.g. w=3 means write to the primary and wait until replicated to two secondaries). Setting w=0 disables write acknowledgement and all other write concern options.
    - wtimeout: (integer) Used in conjunction with w. Specify a value in milliseconds to control how long to wait for write propagation to complete. If replication does not complete in the given timeframe, a timeout exception is raised.
    - j: If `True` block until write operations have been committed to the journal. Ignored if the server is running without journaling.
    - fsync: If `True` force the database to fsync all files before returning. When used with j the server awaits the next group commit before returning.

        >>> m = pymongo.MongoClient()
        >>> m.write_concern
        {}
        >>> m.write_concern = {'w': 2, 'wtimeout': 1000}
        >>> m.write_concern
        {'wtimeout': 1000, 'w': 2}
        >>> m.write_concern['j'] = True
        >>> m.write_concern
        {'wtimeout': 1000, 'j': True, 'w': 2}
        >>> m.write_concern = {'j': True}
        >>> m.write_concern
        {'j': True}
        >>> # Disable write acknowledgement and write concern
        ...
        >>> m.write_concern['w'] = 0

    Note

    Accessing `write_concern` returns its value (a subclass of `dict`), not a copy.

    Warning

    If you are using `Connection` or `ReplicaSetConnection` make sure you explicitly set `w` to 1 (or a greater value) or `safe` to `True`. Unlike calling `set_lasterror_options()`, setting an option in `write_concern` does not implicitly set `safe` to `True`.

  `uuid_subtype`

    This attribute specifies which BSON Binary subtype is used when storing UUIDs. Historically UUIDs have been stored as BSON Binary subtype 3. This attribute is used to switch to the newer BSON binary subtype 4. It can also be used to force legacy byte order and subtype compatibility with the Java and C# drivers. See the `bson.binary` module for all options.

  `insert`(doc_or_docs[, manipulate=True[, safe=None[, check_keys=True[, continue_on_error=False[, **kwargs]]]]])

    Insert a document(s) into this collection.

    If manipulate is `True`, the document(s) are manipulated using any `SONManipulator` instances that have been added to this `Database`. In this case an `"_id"` will be added if the document(s) does not already contain one and the `"id"` (or list of `"_id"` values for more than one document) will be returned. If manipulate is `False` and the document(s) does not include an `"_id"` one will be added by the server. The server does not return the `"_id"` it created so `None` is returned.

    Write concern options can be passed as keyword arguments, overriding any global defaults. Valid options include w=<int/string>, wtimeout=<int>, j=<bool>, or fsync=<bool>. See the parameter list below for a detailed explanation of these options.

    By default an acknowledgment is requested from the server that the insert was successful, raising `OperationFailure` if an error occurred. Passing ``w=0`` disables write acknowledgement and all other write concern options.

    Parameters : | doc_or_docs: a document or list of documents to be inserted manipulate (optional): If `True` manipulate the documents before inserting. safe (optional): DEPRECATED - Use w instead. check_keys (optional): If `True` check if keys start with ‘$’ or contain ‘.’, raising `InvalidName` in either case. continue_on_error (optional): If `True`, the database will not stop processing a bulk insert if one fails (e.g. due to duplicate IDs). This makes bulk insert behave similarly to a series of single inserts, except lastError will be set if any insert fails, not just the last one. If multiple errors occur, only the most recent will be reported by `error()`. w (optional): (integer or string) If this is a replica set, write operations will block until they have been replicated to the specified number or tagged set of servers. w=<int> always includes the replica set primary (e.g. w=3 means write to the primary and wait until replicated to two secondaries). Passing w=0 disables write acknowledgement and all other write concern options. wtimeout (optional): (integer) Used in conjunction with w. Specify a value in milliseconds to control how long to wait for write propagation to complete. If replication does not complete in the given timeframe, a timeout exception is raised. j (optional): If `True` block until write operations have been committed to the journal. Ignored if the server is running without journaling. fsync (optional): If `True` force the database to fsync all files before returning. When used with j the server awaits the next group commit before returning.
    Returns : | The `'_id'` value (or list of ‘_id’ values) of doc_or_docs or `[None]` if manipulate is `False` and the documents passed as doc_or_docs do not include an ‘_id’ field.

    Note

    continue_on_error requires server version >= 1.9.1

    New in version 2.1: Support for continue_on_error.

    New in version 1.8: Support for passing getLastError options as keyword arguments.

    Changed in version 1.1: Bulk insert works with any iterable

    See general MongoDB documentation

    insert

  `save`(to_save[, manipulate=True[, safe=None[, check_keys=True[, **kwargs]]]])

    Save a document in this collection.

    If to_save already has an `"_id"` then an `update()` (upsert) operation is performed and any existing document with that `"_id"` is overwritten. Otherwise an `insert()` operation is performed. In this case if manipulate is `True` an `"_id"` will be added to to_save and this method returns the `"_id"` of the saved document. If manipulate is `False` the `"_id"` will be added by the server but this method will return `None`.

    Raises `TypeError` if to_save is not an instance of `dict`.

    Write concern options can be passed as keyword arguments, overriding any global defaults. Valid options include w=<int/string>, wtimeout=<int>, j=<bool>, or fsync=<bool>. See the parameter list below for a detailed explanation of these options.

    By default an acknowledgment is requested from the server that the save was successful, raising `OperationFailure` if an error occurred. Passing ``w=0`` disables write acknowledgement and all other write concern options.

    Parameters : | to_save: the document to be saved manipulate (optional): manipulate the document before saving it? safe (optional): DEPRECATED - Use w instead. check_keys (optional): check if keys start with ‘$’ or contain ‘.’, raising `InvalidName` in either case. w (optional): (integer or string) If this is a replica set, write operations will block until they have been replicated to the specified number or tagged set of servers. w=<int> always includes the replica set primary (e.g. w=3 means write to the primary and wait until replicated to two secondaries). Passing w=0 disables write acknowledgement and all other write concern options. wtimeout (optional): (integer) Used in conjunction with w. Specify a value in milliseconds to control how long to wait for write propagation to complete. If replication does not complete in the given timeframe, a timeout exception is raised. j (optional): If `True` block until write operations have been committed to the journal. Ignored if the server is running without journaling. fsync (optional): If `True` force the database to fsync all files before returning. When used with j the server awaits the next group commit before returning.
    Returns : | The `'_id'` value of to_save or `[None]` if manipulate is `False` and to_save has no ‘_id’ field.

    New in version 1.8: Support for passing getLastError options as keyword arguments.

    See general MongoDB documentation

    insert

  `update`(spec, document[, upsert=False[, manipulate=False[, safe=None[, multi=False[, check_keys=True[, **kwargs]]]]]])

    Update a document(s) in this collection.

    Raises `TypeError` if either spec or document is not an instance of `dict` or upsert is not an instance of `bool`.

    Write concern options can be passed as keyword arguments, overriding any global defaults. Valid options include w=<int/string>, wtimeout=<int>, j=<bool>, or fsync=<bool>. See the parameter list below for a detailed explanation of these options.

    By default an acknowledgment is requested from the server that the update was successful, raising `OperationFailure` if an error occurred. Passing ``w=0`` disables write acknowledgement and all other write concern options.

    There are many useful update modifiers which can be used when performing updates. For example, here we use the `"$set"` modifier to modify some fields in a matching document:

        >>> db.test.insert({"x": "y", "a": "b"})
        ObjectId('...')
        >>> list(db.test.find())
        [{u'a': u'b', u'x': u'y', u'_id': ObjectId('...')}]
        >>> db.test.update({"x": "y"}, {"$set": {"a": "c"}})
        {...}
        >>> list(db.test.find())
        [{u'a': u'c', u'x': u'y', u'_id': ObjectId('...')}]

    Parameters : | spec: a `dict` or `SON` instance specifying elements which must be present for a document to be updated document: a `dict` or `SON` instance specifying the document to be used for the update or (in the case of an upsert) insert - see docs on MongoDB update modifiers upsert (optional): perform an upsert if `True` manipulate (optional): manipulate the document before updating? If `True` all instances of `SONManipulator` added to this `Database` will be applied to the document before performing the update. check_keys (optional): check if keys in document start with ‘$’ or contain ‘.’, raising `InvalidName`. Only applies to document replacement, not modification through $ operators. safe (optional): DEPRECATED - Use w instead. multi (optional): update all documents that match spec, rather than just the first matching document. The default value for multi is currently `False`, but this might eventually change to `True`. It is recommended that you specify this argument explicitly for all update operations in order to prepare your code for that change. w (optional): (integer or string) If this is a replica set, write operations will block until they have been replicated to the specified number or tagged set of servers. w=<int> always includes the replica set primary (e.g. w=3 means write to the primary and wait until replicated to two secondaries). Passing w=0 disables write acknowledgement and all other write concern options. wtimeout (optional): (integer) Used in conjunction with w. Specify a value in milliseconds to control how long to wait for write propagation to complete. If replication does not complete in the given timeframe, a timeout exception is raised. j (optional): If `True` block until write operations have been committed to the journal. Ignored if the server is running without journaling. fsync (optional): If `True` force the database to fsync all files before returning. When used with j the server awaits the next group commit before returning.
    Returns : | A document (dict) describing the effect of the update or `None` if write acknowledgement is disabled.

    New in version 1.8: Support for passing getLastError options as keyword arguments.

    Changed in version 1.4: Return the response to lastError if safe is `True`.

    New in version 1.1.1: The multi parameter.

    See general MongoDB documentation

    update

  `remove`([spec_or_id=None[, safe=None[, **kwargs]]])

    Remove a document(s) from this collection.

    Warning

    Calls to `remove()` should be performed with care, as removed data cannot be restored.

    If spec_or_id is `None`, all documents in this collection will be removed. This is not equivalent to calling `drop_collection()`, however, as indexes will not be removed.

    Write concern options can be passed as keyword arguments, overriding any global defaults. Valid options include w=<int/string>, wtimeout=<int>, j=<bool>, or fsync=<bool>. See the parameter list below for a detailed explanation of these options.

    By default an acknowledgment is requested from the server that the remove was successful, raising `OperationFailure` if an error occurred. Passing ``w=0`` disables write acknowledgement and all other write concern options.

    Parameters : | spec_or_id (optional): a dictionary specifying the documents to be removed OR any other type specifying the value of `"_id"` for the document to be removed safe (optional): DEPRECATED - Use w instead. w (optional): (integer or string) If this is a replica set, write operations will block until they have been replicated to the specified number or tagged set of servers. w=<int> always includes the replica set primary (e.g. w=3 means write to the primary and wait until replicated to two secondaries). Passing w=0 disables write acknowledgement and all other write concern options. wtimeout (optional): (integer) Used in conjunction with w. Specify a value in milliseconds to control how long to wait for write propagation to complete. If replication does not complete in the given timeframe, a timeout exception is raised. j (optional): If `True` block until write operations have been committed to the journal. Ignored if the server is running without journaling. fsync (optional): If `True` force the database to fsync all files before returning. When used with j the server awaits the next group commit before returning.
    Returns : | A document (dict) describing the effect of the remove or `None` if write acknowledgement is disabled.

    New in version 1.8: Support for passing getLastError options as keyword arguments.

    Changed in version 1.7: Accept any type other than a `dict` instance for removal by `"_id"`, not just `ObjectId` instances.

    Changed in version 1.4: Return the response to lastError if safe is `True`.

    Changed in version 1.2: The spec_or_id parameter is now optional. If it is not specified all documents in the collection will be removed.

    New in version 1.1: The safe parameter.

    See general MongoDB documentation

    remove

  `drop`()

    Alias for `drop_collection()`.

    The following two calls are equivalent:

        >>> db.foo.drop()
        >>> db.drop_collection("foo")

    New in version 1.8.

  `find`([spec=None[, fields=None[, skip=0[, limit=0[, timeout=True[, snapshot=False[, tailable=False[, sort=None[, max_scan=None[, as_class=None[, slave_okay=False[, await_data=False[, partial=False[, manipulate=True[, read_preference=ReadPreference.PRIMARY[, **kwargs]]]]]]]]]]]]]]]])

    Query the database.

    The spec argument is a prototype document that all results must match. For example:

        >>> db.test.find({"hello": "world"})

    only matches documents that have a key “hello” with value “world”. Matches can have other keys in addition to “hello”. The fields argument is used to specify a subset of fields that should be included in the result documents. By limiting results to a certain subset of fields you can cut down on network traffic and decoding time.

    Raises `TypeError` if any of the arguments are of improper type. Returns an instance of `Cursor` corresponding to this query.

    Parameters : | spec (optional): a SON object specifying elements which must be present for a document to be included in the result set fields (optional): a list of field names that should be returned in the result set or a dict specifying the fields to include or exclude. If fields is a list “_id” will always be returned. Use a dict to exclude fields from the result (e.g. fields={‘_id’: False}). skip (optional): the number of documents to omit (from the start of the result set) when returning the results limit (optional): the maximum number of results to return timeout (optional): if True, any returned cursor will be subject to the normal timeout behavior of the mongod process. Otherwise, the returned cursor will never timeout at the server. Care should be taken to ensure that cursors with timeout turned off are properly closed. snapshot (optional): if True, snapshot mode will be used for this query. Snapshot mode assures no duplicates are returned, or objects missed, which were present at both the start and end of the query’s execution. For details, see the snapshot documentation. tailable (optional): the result of this find call will be a tailable cursor - tailable cursors aren’t closed when the last data is retrieved but are kept open and the cursors location marks the final document’s position. if more data is received iteration of the cursor will continue from the last document received. For details, see the tailable cursor documentation. sort (optional): a list of (key, direction) pairs specifying the sort order for this query. See `sort()` for details. max_scan (optional): limit the number of documents examined when performing the query as_class (optional): class to use for documents in the query result (default is `document_class`) slave_okay (optional): if True, allows this query to be run against a replica secondary. await_data (optional): if True, the server will block for some extra time before returning, waiting for more data to return. Ignored if tailable is False. partial (optional): if True, mongos will return partial results if some shards are down instead of returning an error. manipulate: (optional): If True (the default), apply any outgoing SON manipulators before returning. network_timeout (optional): specify a timeout to use for this query, which will override the `MongoClient`-level default read_preference (optional): The read preference for this query. tag_sets (optional): The tag sets for this query. secondary_acceptable_latency_ms (optional): Any replica-set member whose ping time is within secondary_acceptable_latency_ms of the nearest member may accept reads. Default 15 milliseconds. Ignored by mongos and must be configured on the command line. See the localThreshold option for more information.

    Note

    The manipulate parameter may default to False in a future release.

    Note

    The max_scan parameter requires server version >= 1.5.1

    New in version 2.3: The tag_sets and secondary_acceptable_latency_ms parameters.

    New in version 1.11+: The await_data, partial, and manipulate parameters.

    New in version 1.8: The network_timeout parameter.

    New in version 1.7: The sort, max_scan and as_class parameters.

    Changed in version 1.7: The fields parameter can now be a dict or any iterable in addition to a list.

    New in version 1.1: The tailable parameter.

    See general MongoDB documentation

    find

  `find_one`([spec_or_id=None[, *args[, **kwargs]]])

    Get a single document from the database.

    All arguments to `find()` are also valid arguments for `find_one()`, although any limit argument will be ignored. Returns a single document, or `None` if no matching document is found.

    Parameters : | spec_or_id (optional): a dictionary specifying the query to be performed OR any other type to be used as the value for a query for `"_id"`. *args (optional): any additional positional arguments are the same as the arguments to `find()`. **kwargs (optional): any additional keyword arguments are the same as the arguments to `find()`.

    Changed in version 1.7: Allow passing any of the arguments that are valid for `find()`.

    Changed in version 1.7: Accept any type other than a `dict` instance as an `"_id"` query, not just `ObjectId` instances.

  `count`()

    Get the number of documents in this collection.

    To get the number of documents matching a specific query use `pymongo.cursor.Cursor.count()`.

  `create_index`(key_or_list, cache_for=300, **kwargs)

    Creates an index on this collection.

    Takes either a single key or a list of (key, direction) pairs. The key(s) must be an instance of `basestring` (`str` in python 3), and the directions must be one of (`ASCENDING`, `DESCENDING`, `GEO2D`). Returns the name of the created index.

    To create a single key index on the key `'mike'` we just use a string argument:

        >>> my_collection.create_index("mike")

    For a compound index on `'mike'` descending and `'eliot'` ascending we need to use a list of tuples:

        >>> my_collection.create_index([("mike", pymongo.DESCENDING),
        ...                             ("eliot", pymongo.ASCENDING)])

    All optional index creation paramaters should be passed as keyword arguments to this method. Valid options include:

    > - name: custom name to use for this index - if none is given, a name will be generated
    > - unique: should this index guarantee uniqueness?
    > - dropDups or drop_dups: should we drop duplicates
    > - background: if this index should be created in the background
    > - bucketSize or bucket_size: for use with geoHaystack indexes. Number of documents to group together within a certain proximity to a given longitude and latitude.
    > - min: minimum value for keys in a `GEO2D` index
    > - max: maximum value for keys in a `GEO2D` index
    > - expireAfterSeconds: <int> Used to create an expiring (TTL) collection. MongoDB will automatically delete documents from this collection after <int> seconds. The indexed field must be a UTC datetime or the data will not expire.

    Note

    expireAfterSeconds requires server version >= 2.1.2

    Parameters : | key_or_list: a single key or a list of (key, direction) pairs specifying the index to create cache_for (optional): time window (in seconds) during which this index will be recognized by subsequent calls to `ensure_index()` - see documentation for `ensure_index()` for details **kwargs (optional): any additional index creation options (see the above list) should be passed as keyword arguments ttl (deprecated): Use cache_for instead.

    Changed in version 2.3: The ttl parameter has been deprecated to avoid confusion with TTL collections. Use cache_for instead.

    Changed in version 2.2: Removed deprecated argument: deprecated_unique

    Changed in version 1.5.1: Accept kwargs to support all index creation options.

    New in version 1.5: The name parameter.

    See also

    `ensure_index()`

    See general MongoDB documentation

    indexes

  `ensure_index`(key_or_list, cache_for=300, **kwargs)

    Ensures that an index exists on this collection.

    Takes either a single key or a list of (key, direction) pairs. The key(s) must be an instance of `basestring` (`str` in python 3), and the direction(s) must be one of (`ASCENDING`, `DESCENDING`, `GEO2D`). See `create_index()` for a detailed example.

    Unlike `create_index()`, which attempts to create an index unconditionally, `ensure_index()` takes advantage of some caching within the driver such that it only attempts to create indexes that might not already exist. When an index is created (or ensured) by PyMongo it is “remembered” for cache_for seconds. Repeated calls to `ensure_index()` within that time limit will be lightweight - they will not attempt to actually create the index.

    Care must be taken when the database is being accessed through multiple clients at once. If an index is created using this client and deleted using another, any call to `ensure_index()` within the cache window will fail to re-create the missing index.

    Returns the name of the created index if an index is actually created. Returns `None` if the index already exists.

    All optional index creation paramaters should be passed as keyword arguments to this method. Valid options include:

    > - name: custom name to use for this index - if none is given, a name will be generated
    > - unique: should this index guarantee uniqueness?
    > - dropDups or drop_dups: should we drop duplicates during index creation when creating a unique index?
    > - background: if this index should be created in the background
    > - bucketSize or bucket_size: for use with geoHaystack indexes. Number of documents to group together within a certain proximity to a given longitude and latitude.
    > - min: minimum value for keys in a `GEO2D` index
    > - max: maximum value for keys in a `GEO2D` index
    > - expireAfterSeconds: <int> Used to create an expiring (TTL) collection. MongoDB will automatically delete documents from this collection after <int> seconds. The indexed field must be a UTC datetime or the data will not expire.

    Note

    expireAfterSeconds requires server version >= 2.1.2

    Parameters : | key_or_list: a single key or a list of (key, direction) pairs specifying the index to create cache_for (optional): time window (in seconds) during which this index will be recognized by subsequent calls to `ensure_index()` **kwargs (optional): any additional index creation options (see the above list) should be passed as keyword arguments ttl (deprecated): Use cache_for instead.

    Changed in version 2.3: The ttl parameter has been deprecated to avoid confusion with TTL collections. Use cache_for instead.

    Changed in version 2.2: Removed deprecated argument: deprecated_unique

    Changed in version 1.5.1: Accept kwargs to support all index creation options.

    New in version 1.5: The name parameter.

    See also

    `create_index()`

  `drop_index`(index_or_name)

    Drops the specified index on this collection.

    Can be used on non-existant collections or collections with no indexes. Raises OperationFailure on an error. index_or_name can be either an index name (as returned by create_index), or an index specifier (as passed to create_index). An index specifier should be a list of (key, direction) pairs. Raises TypeError if index is not an instance of (str, unicode, list).

    Warning

    if a custom name was used on index creation (by passing the name parameter to `create_index()` or `ensure_index()`) the index must be dropped by name.

    Parameters : | index_or_name: index (or name of index) to drop

  `drop_indexes`()

    Drops all indexes on this collection.

    Can be used on non-existant collections or collections with no indexes. Raises OperationFailure on an error.

  `reindex`()

    Rebuilds all indexes on this collection.

    Warning

    reindex blocks all other operations (indexes are built in the foreground) and will be slow for large collections.

    New in version 1.11+.

  `index_information`()

    Get information on this collection’s indexes.

    Returns a dictionary where the keys are index names (as returned by create_index()) and the values are dictionaries containing information about each index. The dictionary is guaranteed to contain at least a single key, `"key"` which is a list of (key, direction) pairs specifying the index (as passed to create_index()). It will also contain any other information in system.indexes, except for the `"ns"` and `"name"` keys, which are cleaned. Example output might look like this:

        >>> db.test.ensure_index("x", unique=True)
        u'x_1'
        >>> db.test.index_information()
        {u'_id_': {u'key': [(u'_id', 1)]},
         u'x_1': {u'unique': True, u'key': [(u'x', 1)]}}

    Changed in version 1.7: The values in the resultant dictionary are now dictionaries themselves, whose `"key"` item contains the list that was the value in previous versions of PyMongo.

  `options`()

    Get the options set on this collection.

    Returns a dictionary of options and their values - see `create_collection()` for more information on the possible options. Returns an empty dictionary if the collection has not been created yet.

  `aggregate`(pipeline)

    Perform an aggregation using the aggregation framework on this collection.

    With `MongoReplicaSetClient` or `MasterSlaveConnection`, if the read_preference attribute of this instance is not set to `pymongo.read_preferences.ReadPreference.PRIMARY` or the (deprecated) slave_okay attribute of this instance is set to True the aggregate command will be sent to a secondary or slave.

    Parameters : | pipeline: a single command or list of aggregation commands

    Note

    Requires server version >= 2.1.0

    New in version 2.3.

  `group`(key, condition, initial, reduce, finalize=None)

    Perform a query similar to an SQL group by operation.

    Returns an array of grouped items.

    The key parameter can be:

    > - `None` to use the entire document as a key.
    > - A `list` of keys (each a `basestring` (`str` in python 3)) to group by.
    > - A `basestring` (`str` in python 3), or `Code` instance containing a JavaScript function to be applied to each document, returning the key to group by.

    With `MongoReplicaSetClient` or `MasterSlaveConnection`, if the read_preference attribute of this instance is not set to `pymongo.read_preferences.ReadPreference.PRIMARY` or `pymongo.read_preferences.ReadPreference.PRIMARY_PREFERRED`, or the (deprecated) slave_okay attribute of this instance is set to True, the group command will be sent to a secondary or slave.

    Parameters : | key: fields to group by (see above description) condition: specification of rows to be considered (as a `find()` query specification) initial: initial value of the aggregation counter object reduce: aggregation function as a JavaScript string finalize: function to be called on each object in output list.

    Changed in version 2.2: Removed deprecated argument: command

    Changed in version 1.4: The key argument can now be `None` or a JavaScript function, in addition to a `list` of keys.

    Changed in version 1.3: The command argument now defaults to `True` and is deprecated.

  `rename`(new_name, **kwargs)

    Rename this collection.

    If operating in auth mode, client must be authorized as an admin to perform this operation. Raises `TypeError` if new_name is not an instance of `basestring` (`str` in python 3). Raises `InvalidName` if new_name is not a valid collection name.

    Parameters : | new_name: new name for this collection **kwargs (optional): any additional rename options should be passed as keyword arguments (i.e. `dropTarget=True`)

    New in version 1.7: support for accepting keyword arguments for rename options

  `distinct`(key)

    Get a list of distinct values for key among all documents in this collection.

    Raises `TypeError` if key is not an instance of `basestring` (`str` in python 3).

    To get the distinct values for a key in the result set of a query use `distinct()`.

    Parameters : | key: name of key for which we want to get the distinct values

    Note

    Requires server version >= 1.1.0

    New in version 1.1.1.

  `map_reduce`(map, reduce, out, full_response=False, **kwargs)

    Perform a map/reduce operation on this collection.

    If full_response is `False` (default) returns a `Collection` instance containing the results of the operation. Otherwise, returns the full response from the server to the map reduce command.

    - Parameters : | map: map function (as a JavaScript string) reduce: reduce function (as a JavaScript string) out: output collection name or out object (dict). See the map reduce command documentation for available options. Note: out options are order sensitive. `SON` can be used to specify multiple options. e.g. SON([(‘replace’, <collection name>), (‘db’, <database name>)]) full_response (optional): if `True`, return full response to this command - otherwise just return the result collection **kwargs (optional): additional arguments to the map reduce command may be passed as keyword arguments to this helper method, e.g.:
          >>> db.test.map_reduce(map, reduce, "myresults", limit=2)

    Note

    Requires server version >= 1.1.1

    See also

    Aggregation Examples

    Changed in version 2.2: Removed deprecated arguments: merge_output and reduce_output

    Changed in version 1.11+: DEPRECATED The merge_output and reduce_output parameters.

    New in version 1.2.

    See general MongoDB documentation

    mapreduce

  `inline_map_reduce`(map, reduce, full_response=False, **kwargs)

    Perform an inline map/reduce operation on this collection.

    Perform the map/reduce operation on the server in RAM. A result collection is not created. The result set is returned as a list of documents.

    If full_response is `False` (default) returns the result documents in a list. Otherwise, returns the full response from the server to the map reduce command.

    With `MongoReplicaSetClient` or `MasterSlaveConnection`, if the read_preference attribute of this instance is not set to `pymongo.read_preferences.ReadPreference.PRIMARY` or `pymongo.read_preferences.ReadPreference.PRIMARY_PREFERRED`, or the (deprecated) slave_okay attribute of this instance is set to True, the inline map reduce will be run on a secondary or slave.

    - Parameters : | map: map function (as a JavaScript string) reduce: reduce function (as a JavaScript string) full_response (optional): if `True`, return full response to this command - otherwise just return the result collection **kwargs (optional): additional arguments to the map reduce command may be passed as keyword arguments to this helper method, e.g.:
          >>> db.test.inline_map_reduce(map, reduce, limit=2)

    Note

    Requires server version >= 1.7.4

    New in version 1.10.

  `find_and_modify`(query={}, update=None, upsert=False, sort=None, full_response=False, **kwargs)

    Update and return an object.

    This is a thin wrapper around the findAndModify command. The positional arguments are designed to match the first three arguments to `update()` however most options should be passed as named parameters. Either update or remove arguments are required, all others are optional.

    Returns either the object before or after modification based on new parameter. If no objects match the query and upsert is false, returns `None`. If upserting and new is false, returns `{}`.

    If the full_response parameter is `True`, the return value will be the entire response object from the server, including the ‘ok’ and ‘lastErrorObject’ fields, rather than just the modified object. This is useful mainly because the ‘lastErrorObject’ document holds information about the command’s execution.

    Parameters : | query: filter for the update (default `{}`) update: see second argument to `update()` (no default) upsert: insert if object doesn’t exist (default `False`) sort: a list of (key, direction) pairs specifying the sort order for this query. See `sort()` for details. full_response: return the entire response object from the server (default `False`) remove: remove rather than updating (default `False`) new: return updated rather than original object (default `False`) fields: see second argument to `find()` (default all) **kwargs: any other options the findAndModify command supports can be passed here.

    See general MongoDB documentation

    findAndModify

    Note

    Requires server version >= 1.3.0

    Changed in version 2.5: Added the optional full_response parameter

    Changed in version 2.4: Deprecated the use of mapping types for the sort parameter

    New in version 1.10.

  `slave_okay`

    DEPRECATED. Use `read_preference` instead.

    Changed in version 2.1: Deprecated slave_okay.

    New in version 2.0.

  `safe`

    DEPRECATED: Use the ‘w’ `write_concern` option instead.

    Use getlasterror with every write operation?

    New in version 2.0.

  `get_lasterror_options`()

    DEPRECATED: Use `write_concern` instead.

    Returns a dict of the getlasterror options set on this instance.

    Changed in version 2.4: Deprecated get_lasterror_options.

    New in version 2.0.

  `set_lasterror_options`(**kwargs)

    DEPRECATED: Use `write_concern` instead.

    Set getlasterror options for this instance.

    Valid options include j=<bool>, w=<int/string>, wtimeout=<int>, and fsync=<bool>. Implies safe=True.

    Parameters : | **kwargs: Options should be passed as keyword arguments (e.g. w=2, fsync=True)

    Changed in version 2.4: Deprecated set_lasterror_options.

    New in version 2.0.

  `unset_lasterror_options`(*options)

    DEPRECATED: Use `write_concern` instead.

    Unset getlasterror options for this instance.

    If no options are passed unsets all getlasterror options. This does not set safe to False.

    Parameters : | *options: The list of options to unset.

    Changed in version 2.4: Deprecated unset_lasterror_options.

    New in version 2.0.

### Navigation

- index
- modules |
- next |
- previous |
- PyMongo 2.5 documentation »
- API Documentation »
- `pymongo` – Python driver for MongoDB »