`database` – Database level operations¶

Database level operations.

pymongo.auth.MECHANISMS = frozenset({'DEFAULT', 'GSSAPI', 'MONGODB-AWS', 'MONGODB-CR', 'MONGODB-X509', 'PLAIN', 'SCRAM-SHA-1', 'SCRAM-SHA-256'})¶: The authentication mechanisms supported by PyMongo.

class pymongo.database.Database(client: MongoClient[_DocumentType], name: str, codec_options: Optional[bson.codec_options.CodecOptions] = None, read_preference: Optional[pymongo.read_preferences._ServerMode] = None, write_concern: Optional[WriteConcern] = None, read_concern: Optional[ReadConcern] = None)¶

Get a database by client and name.

Raises TypeError if name is not an instance of basestring (str in python 3). Raises InvalidName if name is not a valid database name.

Parameters

client: A MongoClient instance.
name: The database name.
codec_options (optional): An instance of CodecOptions. If None (the default) client.codec_options is used.
read_preference (optional): The read preference to use. If None (the default) client.read_preference is used.
write_concern (optional): An instance of WriteConcern. If None (the default) client.write_concern is used.
read_concern (optional): An instance of ReadConcern. If None (the default) client.read_concern is used.

See also

The MongoDB documentation on databases.

Changed in version 4.0: Removed the eval, system_js, error, last_status, previous_error, reset_error_history, authenticate, logout, collection_names, current_op, add_user, remove_user, profiling_level, set_profiling_level, and profiling_info methods. See the PyMongo 4 Migration Guide.

Changed in version 3.2: Added the read_concern option.

Changed in version 3.0: Added the codec_options, read_preference, and write_concern options. Database no longer returns an instance of Collection for attribute names with leading underscores. You must use dict-style lookups instead::

db[‘__my_collection__’]

Not:

db.__my_collection__

db[collection_name] || db.collection_name

Get the collection_name Collection of Database db.

Raises InvalidName if an invalid collection name is used.

Note

Use dictionary style access if collection_name is an attribute of the Database class eg: db[collection_name].

codec_options¶: Read only access to the CodecOptions of this instance.

read_preference¶: Read only access to the read preference of this instance.

Changed in version 3.0: The read_preference attribute is now read only.

write_concern¶: Read only access to the WriteConcern of this instance.

Changed in version 3.0: The write_concern attribute is now read only.

read_concern¶: Read only access to the ReadConcern of this instance.

New in version 3.2.

aggregate(pipeline: Sequence[Mapping[str, Any]], session: Optional[ClientSession] = None, **kwargs: Any) → pymongo.command_cursor.CommandCursor[pymongo.typings._DocumentType]¶

Perform a database-level aggregation.

See the aggregation pipeline documentation for a list of stages that are supported.

# Lists all operations currently running on the server.
with client.admin.aggregate([{"$currentOp": {}}]) as cursor:
    for operation in cursor:
        print(operation)

The aggregate() method obeys the read_preference of this Database, except when $out or $merge are used, in which case PRIMARY is used.

Note

This method does not support the ‘explain’ option. Please use command() instead.

Note

The write_concern of this collection is automatically applied to this operation.

Parameters

pipeline: a list of aggregation pipeline stages
session (optional): a ClientSession.
**kwargs (optional): extra aggregate command parameters.

All optional aggregate command parameters should be passed as keyword arguments to this method. Valid options include, but are not limited to:

allowDiskUse (bool): Enables writing to temporary files. When set to True, aggregation stages can write data to the _tmp subdirectory of the –dbpath directory. The default is False.

maxTimeMS (int): The maximum amount of time to allow the operation to run in milliseconds.

batchSize (int): The maximum number of documents to return per batch. Ignored if the connected mongod or mongos does not support returning aggregate results using a cursor.

collation (optional): An instance of Collation.

let (dict): A dict of parameter names and values. Values must be constant or closed expressions that do not reference document fields. Parameters can then be accessed as variables in an aggregate expression context (e.g. "$$var"). This option is only supported on MongoDB >= 5.0.

Returns: A CommandCursor over the result set.

New in version 3.9.

property client: MongoClient[_DocumentType]¶: The client instance for this Database.

command(command: Union[str, MutableMapping[str, Any]], value: Any = 1, check: bool = True, allowable_errors: Optional[Sequence[Union[str, int]]] = None, read_preference: Optional[pymongo.read_preferences._ServerMode] = None, codec_options: Optional[bson.codec_options.CodecOptions[_CodecDocumentType]] = None, session: Optional[ClientSession] = None, comment: Optional[Any] = None, **kwargs: Any) → pymongo.database._CodecDocumentType¶

Issue a MongoDB command.

Send command command to the database and return the response. If command is an instance of basestring (str in python 3) then the command {command: value} will be sent. Otherwise, command must be an instance of dict and will be sent as is.

Any additional keyword arguments will be added to the final command document before it is sent.

For example, a command like {buildinfo: 1} can be sent using:

>>> db.command("buildinfo")

For a command where the value matters, like {collstats: collection_name} we can do:

>>> db.command("collstats", collection_name)

For commands that take additional arguments we can use kwargs. So {filemd5: object_id, root: file_root} becomes:

>>> db.command("filemd5", object_id, root=file_root)

Parameters

command: document representing the command to be issued, or the name of the command (for simple commands only).

Note

the order of keys in the command document is significant (the “verb” must come first), so commands which require multiple keys (e.g. findandmodify) should use an instance of SON or a string and kwargs instead of a Python dict.
value (optional): value to use for the command verb when command is passed as a string
check (optional): check the response for errors, raising OperationFailure if there are any
allowable_errors: if check is True, error messages in this list will be ignored by error-checking
read_preference (optional): The read preference for this operation. See read_preferences for options. If the provided session is in a transaction, defaults to the read preference configured for the transaction. Otherwise, defaults to PRIMARY.
codec_options: A CodecOptions instance.
session (optional): A ClientSession.
comment (optional): A user-provided comment to attach to this command.
**kwargs (optional): additional keyword arguments will be added to the command document before it is sent

Note

command() does not obey this Database’s read_preference or codec_options. You must use the read_preference and codec_options parameters instead.

Note

command() does not apply any custom TypeDecoders when decoding the command response.

Note

If this client has been configured to use MongoDB Stable API (see MongoDB Stable API), then command() will automatically add API versioning options to the given command. Explicitly adding API versioning options in the command and declaring an API version on the client is not supported.

Changed in version 3.6: Added session parameter.

Changed in version 3.0: Removed the as_class, fields, uuid_subtype, tag_sets, and secondary_acceptable_latency_ms option. Removed compile_re option: PyMongo now always represents BSON regular expressions as Regex objects. Use try_compile() to attempt to convert from a BSON regular expression to a Python regular expression object. Added the codec_options parameter.

See also

The MongoDB documentation on commands.

create_collection(name: str, codec_options: Optional[bson.codec_options.CodecOptions] = None, read_preference: Optional[pymongo.read_preferences._ServerMode] = None, write_concern: Optional[WriteConcern] = None, read_concern: Optional[ReadConcern] = None, session: Optional[ClientSession] = None, check_exists: Optional[bool] = True, **kwargs: Any) → pymongo.collection.Collection[pymongo.typings._DocumentType]¶

Create a new Collection in this database.

Normally collection creation is automatic. This method should only be used to specify options on creation. CollectionInvalid will be raised if the collection already exists.

Parameters

name: the name of the collection to create
codec_options (optional): An instance of CodecOptions. If None (the default) the codec_options of this Database is used.
read_preference (optional): The read preference to use. If None (the default) the read_preference of this Database is used.
write_concern (optional): An instance of WriteConcern. If None (the default) the write_concern of this Database is used.
read_concern (optional): An instance of ReadConcern. If None (the default) the read_concern of this Database is used.
collation (optional): An instance of Collation.
session (optional): a ClientSession.
check_exists (optional): if True (the default), send a listCollections command to check if the collection already exists before creation.
**kwargs (optional): additional keyword arguments will be passed as options for the create collection command

All optional create collection command parameters should be passed as keyword arguments to this method. Valid options include, but are not limited to:

size (int): desired initial size for the collection (in bytes). For capped collections this size is the max size of the collection.

capped (bool): if True, this is a capped collection

max (int): maximum number of objects if capped (optional)

timeseries (dict): a document specifying configuration options for timeseries collections

expireAfterSeconds (int): the number of seconds after which a document in a timeseries collection expires

validator (dict): a document specifying validation rules or expressions for the collection

validationLevel (str): how strictly to apply the validation rules to existing documents during an update. The default level is “strict”

validationAction (str): whether to “error” on invalid documents (the default) or just “warn” about the violations but allow invalid documents to be inserted

indexOptionDefaults (dict): a document specifying a default configuration for indexes when creating a collection

viewOn (str): the name of the source collection or view from which to create the view

pipeline (list): a list of aggregation pipeline stages

comment (str): a user-provided comment to attach to this command. This option is only supported on MongoDB >= 4.4.
encryptedFields (dict): (BETA) Document that describes the encrypted fields for Queryable Encryption. For example:
{
  "escCollection": "enxcol_.encryptedCollection.esc",
  "eccCollection": "enxcol_.encryptedCollection.ecc",
  "ecocCollection": "enxcol_.encryptedCollection.ecoc",
  "fields": [
      {
          "path": "firstName",
          "keyId": Binary.from_uuid(UUID('00000000-0000-0000-0000-000000000000')),
          "bsonType": "string",
          "queries": {"queryType": "equality"}
      },
      {
          "path": "ssn",
          "keyId": Binary.from_uuid(UUID('04104104-1041-0410-4104-104104104104')),
          "bsonType": "string"
      }
    ]
}
clusteredIndex (dict): Document that specifies the clustered index configuration. It must have the following form:
{
    // key pattern must be {_id: 1}
    key: <key pattern>, // required
    unique: <bool>, // required, must be ‘true’
    name: <string>, // optional, otherwise automatically generated
    v: <int>, // optional, must be ‘2’ if provided
}
changeStreamPreAndPostImages (dict): a document with a boolean field enabled for enabling pre- and post-images.

Changed in version 4.2: Added the check_exists, clusteredIndex, and encryptedFields parameters.

Changed in version 3.11: This method is now supported inside multi-document transactions with MongoDB 4.4+.

Changed in version 3.6: Added session parameter.

Changed in version 3.4: Added the collation option.

Changed in version 3.0: Added the codec_options, read_preference, and write_concern options.

dereference(dbref: bson.dbref.DBRef, session: Optional[ClientSession] = None, comment: Optional[Any] = None, **kwargs: Any) → Optional[pymongo.typings._DocumentType]¶

Dereference a DBRef, getting the document it points to.

Raises TypeError if dbref is not an instance of DBRef. Returns a document, or None if the reference does not point to a valid document. Raises ValueError if dbref has a database specified that is different from the current database.

Parameters

dbref: the reference
session (optional): a ClientSession.
comment (optional): A user-provided comment to attach to this command.
**kwargs (optional): any additional keyword arguments are the same as the arguments to find().

Changed in version 4.1: Added comment parameter.

Changed in version 3.6: Added session parameter.

drop_collection(name_or_collection: Union[str, pymongo.collection.Collection], session: Optional[ClientSession] = None, comment: Optional[Any] = None, encrypted_fields: Optional[Mapping[str, Any]] = None) → Dict[str, Any]¶

Drop a collection.

Parameters

name_or_collection: the name of a collection to drop or the collection object itself
session (optional): a ClientSession.
comment (optional): A user-provided comment to attach to this command.

encrypted_fields: (BETA) Document that describes the encrypted fields for Queryable Encryption. For example:

{
  "escCollection": "enxcol_.encryptedCollection.esc",
  "eccCollection": "enxcol_.encryptedCollection.ecc",
  "ecocCollection": "enxcol_.encryptedCollection.ecoc",
  "fields": [
      {
          "path": "firstName",
          "keyId": Binary.from_uuid(UUID('00000000-0000-0000-0000-000000000000')),
          "bsonType": "string",
          "queries": {"queryType": "equality"}
      },
      {
          "path": "ssn",
          "keyId": Binary.from_uuid(UUID('04104104-1041-0410-4104-104104104104')),
          "bsonType": "string"
      }
  ]

}

Note

The write_concern of this database is automatically applied to this operation.

Changed in version 4.2: Added encrypted_fields parameter.

Changed in version 4.1: Added comment parameter.

Changed in version 3.6: Added session parameter.

Changed in version 3.4: Apply this database’s write concern automatically to this operation when connected to MongoDB >= 3.4.

get_collection(name: str, codec_options: Optional[bson.codec_options.CodecOptions] = None, read_preference: Optional[pymongo.read_preferences._ServerMode] = None, write_concern: Optional[WriteConcern] = None, read_concern: Optional[ReadConcern] = None) → pymongo.collection.Collection[pymongo.typings._DocumentType]¶

Get a Collection with the given name and options.

Useful for creating a Collection with different codec options, read preference, and/or write concern from this Database.

>>> db.read_preference
Primary()
>>> coll1 = db.test
>>> coll1.read_preference
Primary()
>>> from pymongo import ReadPreference
>>> coll2 = db.get_collection(
...     'test', read_preference=ReadPreference.SECONDARY)
>>> coll2.read_preference
Secondary(tag_sets=None)

Parameters

name: The name of the collection - a string.
codec_options (optional): An instance of CodecOptions. If None (the default) the codec_options of this Database is used.
read_preference (optional): The read preference to use. If None (the default) the read_preference of this Database is used. See read_preferences for options.
write_concern (optional): An instance of WriteConcern. If None (the default) the write_concern of this Database is used.
read_concern (optional): An instance of ReadConcern. If None (the default) the read_concern of this Database is used.

list_collection_names(session: Optional[ClientSession] = None, filter: Optional[Mapping[str, Any]] = None, comment: Optional[Any] = None, **kwargs: Any) → List[str]¶

Get a list of all the collection names in this database.

For example, to list all non-system collections:

filter = {"name": {"$regex": r"^(?!system\.)"}}
db.list_collection_names(filter=filter)

Parameters

session (optional): a ClientSession.
filter (optional): A query document to filter the list of collections returned from the listCollections command.
comment (optional): A user-provided comment to attach to this command.
**kwargs (optional): Optional parameters of the listCollections command can be passed as keyword arguments to this method. The supported options differ by server version.

Changed in version 3.8: Added the filter and **kwargs parameters.

New in version 3.6.

list_collections(session: Optional[ClientSession] = None, filter: Optional[Mapping[str, Any]] = None, comment: Optional[Any] = None, **kwargs: Any) → pymongo.command_cursor.CommandCursor[Dict[str, Any]]¶

Get a cursor over the collections of this database.

Parameters

session (optional): a ClientSession.
filter (optional): A query document to filter the list of collections returned from the listCollections command.
comment (optional): A user-provided comment to attach to this command.
**kwargs (optional): Optional parameters of the listCollections command can be passed as keyword arguments to this method. The supported options differ by server version.

Returns

An instance of CommandCursor.

New in version 3.6.

property name: str¶: The name of this Database.

validate_collection(name_or_collection: Union[str, pymongo.collection.Collection], scandata: bool = False, full: bool = False, session: Optional[ClientSession] = None, background: Optional[bool] = None, comment: Optional[Any] = None) → Dict[str, Any]¶

Validate a collection.

Returns a dict of validation info. Raises CollectionInvalid if validation fails.

See also the MongoDB documentation on the validate command.

Parameters

name_or_collection: A Collection object or the name of a collection to validate.
scandata: Do extra checks beyond checking the overall structure of the collection.
full: Have the server do a more thorough scan of the collection. Use with scandata for a thorough scan of the structure of the collection and the individual documents.
session (optional): a ClientSession.
background (optional): A boolean flag that determines whether the command runs in the background. Requires MongoDB 4.4+.
comment (optional): A user-provided comment to attach to this command.

Changed in version 4.1: Added comment parameter.

Changed in version 3.11: Added background parameter.

Changed in version 3.6: Added session parameter.

watch(pipeline: Optional[Sequence[Mapping[str, Any]]] = None, full_document: Optional[str] = None, resume_after: Optional[Mapping[str, Any]] = None, max_await_time_ms: Optional[int] = None, batch_size: Optional[int] = None, collation: Optional[Union[Mapping[str, Any], Collation]] = None, start_at_operation_time: Optional[bson.timestamp.Timestamp] = None, session: Optional[ClientSession] = None, start_after: Optional[Mapping[str, Any]] = None, comment: Optional[Any] = None, full_document_before_change: Optional[str] = None) → pymongo.change_stream.DatabaseChangeStream[pymongo.typings._DocumentType]¶

Watch changes on this database.

Performs an aggregation with an implicit initial $changeStream stage and returns a DatabaseChangeStream cursor which iterates over changes on all collections in this database.

Introduced in MongoDB 4.0.

with db.watch() as stream:
    for change in stream:
        print(change)

The DatabaseChangeStream iterable blocks until the next change document is returned or an error is raised. If the next() method encounters a network error when retrieving a batch from the server, it will automatically attempt to recreate the cursor such that no change events are missed. Any error encountered during the resume attempt indicates there may be an outage and will be raised.

try:
    with db.watch(
            [{'$match': {'operationType': 'insert'}}]) as stream:
        for insert_change in stream:
            print(insert_change)
except pymongo.errors.PyMongoError:
    # The ChangeStream encountered an unrecoverable error or the
    # resume attempt failed to recreate the cursor.
    logging.error('...')

For a precise description of the resume process see the change streams specification.

Parameters

pipeline (optional): A list of aggregation pipeline stages to append to an initial $changeStream stage. Not all pipeline stages are valid after a $changeStream stage, see the MongoDB documentation on change streams for the supported stages.
full_document (optional): The fullDocument to pass as an option to the $changeStream stage. Allowed values: ‘updateLookup’, ‘whenAvailable’, ‘required’. When set to ‘updateLookup’, the change notification for partial updates will include both a delta describing the changes to the document, as well as a copy of the entire document that was changed from some time after the change occurred.
full_document_before_change: Allowed values: ‘whenAvailable’ and ‘required’. Change events may now result in a ‘fullDocumentBeforeChange’ response field.
resume_after (optional): A resume token. If provided, the change stream will start returning changes that occur directly after the operation specified in the resume token. A resume token is the _id value of a change document.
max_await_time_ms (optional): The maximum time in milliseconds for the server to wait for changes before responding to a getMore operation.
batch_size (optional): The maximum number of documents to return per batch.
collation (optional): The Collation to use for the aggregation.
start_at_operation_time (optional): If provided, the resulting change stream will only return changes that occurred at or after the specified Timestamp. Requires MongoDB >= 4.0.
session (optional): a ClientSession.
start_after (optional): The same as resume_after except that start_after can resume notifications after an invalidate event. This option and resume_after are mutually exclusive.
comment (optional): A user-provided comment to attach to this command.

Returns

A DatabaseChangeStream cursor.

Changed in version 4.2: Added full_document_before_change parameter.

Changed in version 4.1: Added comment parameter.

Changed in version 3.9: Added the start_after parameter.

New in version 3.7.

`database` – Database level operations¶

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`database` – Database level operations¶