database – Database level operations — PyMongo 2.7.2 documentation

# `database` – Database level operations

Database level operations.

`pymongo.auth.` `MECHANISMS` = frozenset(['PLAIN', 'MONGODB-CR', 'GSSAPI', 'MONGODB-X509'])

  The authentication mechanisms supported by PyMongo.

`pymongo.` `OFF` = 0

  No database profiling.

`pymongo.` `SLOW_ONLY` = 1

  Only profile slow operations.

`pymongo.` `ALL` = 2

  Profile all operations.

class `pymongo.database.` `Database`(connection, name)

  Get a database by connection 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: | connection: a client instance name: database name

  See also

  See general MongoDB documentation

  databases

  `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].

  `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. Cannot be used in combination with fsync. Prior to MongoDB 2.6 this option was ignored if the server was running without journaling. Starting with MongoDB 2.6 write operations will fail with an exception if this option is used when the server is running without journaling.
    - fsync: If `True` and the server is running without journaling, blocks until the server has synced all data files to disk. If the server is running with journaling, this acts the same as the j option, blocking until write operations have been committed to the journal. Cannot be used in combination with j.

        >>> 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.

  `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.

  `add_son_manipulator`(manipulator)

    Add a new son manipulator to this database.

    Newly added manipulators will be applied before existing ones.

    Parameters: | manipulator: the manipulator to add

  `add_user`(name, password=None, read_only=None, **kwargs)

    Create user name with password password.

    Add a new user with permissions for this `Database`.

    Note

    Will change the password if user name already exists.

    Parameters: | name: the name of the user to create password (optional): the password of the user to create. Can not be used with the `userSource` argument. read_only (optional): if `True` the user will be read only **kwargs (optional): optional fields for the user document (e.g. `userSource`, `otherDBRoles`, or `roles`). See http://docs.mongodb.org/manual/reference/privilege-documents for more information.

    Note

    The use of optional keyword arguments like `userSource`, `otherDBRoles`, or `roles` requires MongoDB >= 2.4.0

    Changed in version 2.5: Added kwargs support for optional fields introduced in MongoDB 2.4

    Changed in version 2.2: Added support for read only users

    New in version 1.4.

  `authenticate`(name, password=None, source=None, mechanism='MONGODB-CR', **kwargs)

    Authenticate to use this database.

    Authentication lasts for the life of the underlying client instance, or until `logout()` is called.

    Raises `TypeError` if (required) name, (optional) password, or (optional) source is not an instance of `basestring` (`str` in python 3).

    Note

    - This method authenticates the current connection, and will also cause all new `socket` connections in the underlying client instance to be authenticated automatically.
    - Authenticating more than once on the same database with different credentials is not supported. You must call `logout()` before authenticating with new credentials.
    - When sharing a client instance between multiple threads, all threads will share the authentication. If you need different authentication profiles for different purposes you must use distinct client instances.
    - To get authentication to apply immediately to all existing sockets you may need to reset this client instance’s sockets using `disconnect()`.

    Parameters: | name: the name of the user to authenticate. password (optional): the password of the user to authenticate. Not used with GSSAPI or MONGODB-X509 authentication. source (optional): the database to authenticate on. If not specified the current database is used. mechanism (optional): See `MECHANISMS` for options. Defaults to MONGODB-CR (MongoDB Challenge Response protocol) gssapiServiceName (optional): Used with the GSSAPI mechanism to specify the service name portion of the service principal name. Defaults to ‘mongodb’.

    Changed in version 2.5: Added the source and mechanism parameters. `authenticate()` now raises a subclass of `PyMongoError` if authentication fails due to invalid credentials or configuration issues.

    See also

    See general MongoDB documentation

    authenticate

  `collection_names`(include_system_collections=True)

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

    Parameters: | include_system_collections (optional): if `False` list will not include system collections (e.g `system.indexes`)

  `command`(command, value=1, check=True, allowable_errors=[], uuid_subtype=3, compile_re=True, **kwargs)

    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 uuid_subtype (optional): The BSON binary subtype to use for a UUID used in this command. compile_re (optional): if `False`, don’t attempt to compile BSON regular expressions into Python regular expressions. Return instances of `Regex` instead. Can avoid `InvalidBSON` errors when receiving Python-incompatible regular expressions, for example from `currentOp` read_preference: The read preference for this connection. See `ReadPreference` for available options. tag_sets: Read from replica-set members with these tags. 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. secondary_acceptable_latency_ms: 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. **kwargs (optional): additional keyword arguments will be added to the command document before it is sent

    Note

    `command` ignores the `network_timeout` parameter.

    Changed in version 2.7: Added `compile_re` option.

    Changed in version 2.3: Added tag_sets and secondary_acceptable_latency_ms options.

    Changed in version 2.2: Added support for as_class - the class you want to use for the resulting documents

    Changed in version 1.6: Added the value argument for string commands, and keyword arguments for additional command options.

    Changed in version 1.5: command can be a string in addition to a full document.

    New in version 1.4.

    See also

    See general MongoDB documentation

    commands

  `connection`

    The client instance for this `Database`.

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

  `create_collection`(name, **kwargs)

    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.

    Options should be passed as keyword arguments to this method. Any of the following options are valid:

    > - “size”: desired initial size for the collection (in bytes). For capped collections this size is the max size of the collection.
    > - “capped”: if True, this is a capped collection
    > - “max”: maximum number of objects if capped (optional)

    Parameters: | name: the name of the collection to create **kwargs (optional): additional keyword arguments will be passed as options for the create collection command

    Changed in version 2.2: Removed deprecated argument: options

    Changed in version 1.5: deprecating options in favor of kwargs

  `current_op`(include_all=False)

    Get information on operations currently running.

    Parameters: | include_all (optional): if `True` also list currently idle operations in the result

  `dereference`(dbref)

    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

  `drop_collection`(name_or_collection)

    Drop a collection.

    Parameters: | name_or_collection: the name of a collection to drop or the collection object itself

  `error`()

    Get a database error if one occured on the last operation.

    Return None if the last operation was error-free. Otherwise return the error that occurred.

  `eval`(code, *args)

    Evaluate a JavaScript expression in MongoDB.

    Useful if you need to touch a lot of data lightly; in such a scenario the network transfer of the data could be a bottleneck. The code argument must be a JavaScript function. Additional positional arguments will be passed to that function when it is run on the server.

    Raises `TypeError` if code is not an instance of `basestring` (`str` in python 3) or Code. Raises `OperationFailure` if the eval fails. Returns the result of the evaluation.

    Parameters: | code: string representation of JavaScript code to be evaluated args (optional): additional positional arguments are passed to the code being evaluated

  `incoming_copying_manipulators`

    List all incoming SON copying manipulators installed on this instance.

    New in version 2.0.

  `incoming_manipulators`

    List all incoming SON manipulators installed on this instance.

    New in version 2.0.

  `last_status`()

    Get status information from the last operation.

    Returns a SON object with status information.

  `logout`()

    Deauthorize use of this database for this client instance.

    Note

    Other databases may still be authenticated, and other existing `socket` connections may remain authenticated for this database unless you reset all sockets with `disconnect()`.

  `name`

    The name of this `Database`.

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

  `outgoing_copying_manipulators`

    List all outgoing SON copying manipulators installed on this instance.

    New in version 2.0.

  `outgoing_manipulators`

    List all outgoing SON manipulators installed on this instance.

    New in version 2.0.

  `previous_error`()

    Get the most recent error to have occurred on this database.

    Only returns errors that have occurred since the last call to Database.reset_error_history. Returns None if no such errors have occurred.

  `profiling_info`()

    Returns a list containing current profiling information.

    See also

    See general MongoDB documentation

    profiling

  `profiling_level`()

    Get the database’s current profiling level.

    Returns one of (`OFF`, `SLOW_ONLY`, `ALL`).

    See also

    See general MongoDB documentation

    profiling

  `remove_user`(name)

    Remove user name from this `Database`.

    User name will no longer have permissions to access this `Database`.

    Parameters: | name: the name of the user to remove

    New in version 1.4.

  `reset_error_history`()

    Reset the error history of this database.

    Calls to Database.previous_error will only return errors that have occurred since the most recent call to this method.

  `set_profiling_level`(level, slow_ms=None)

    Set the database’s profiling level.

    Parameters: | level: Specifies a profiling level, see list of possible values below. slow_ms: Optionally modify the threshold for the profile to consider a query or operation. Even if the profiler is off queries slower than the slow_ms level will get written to the logs.

    Possible level values:

    Level | Setting
    --- | ---
    `OFF` | Off. No profiling.
    `SLOW_ONLY` | On. Only includes slow operations.
    `ALL` | On. Includes all operations.

    Raises `ValueError` if level is not one of (`OFF`, `SLOW_ONLY`, `ALL`).

    See also

    See general MongoDB documentation

    profiling

  `system_js`

    A `SystemJS` helper for this `Database`.

    See the documentation for `SystemJS` for more details.

    New in version 1.5.

  `validate_collection`(name_or_collection, scandata=False, full=False)

    Validate a collection.

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

    With MongoDB < 1.9 the result dict will include a result key with a string value that represents the validation results. With MongoDB >= 1.9 the result key no longer exists and the results are split into individual fields in the result dict.

    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. Ignored in MongoDB versions before 1.9.

    Changed in version 1.11: validate_collection previously returned a string.

    New in version 1.11: Added scandata and full options.

class `pymongo.database.` `SystemJS`(database)

  Get a system js helper for the database database.

  An instance of `SystemJS` can be created with an instance of `Database` through `Database.system_js`, manual instantiation of this class should not be necessary.

  `SystemJS` instances allow for easy manipulation and access to server-side JavaScript:

      >>> db.system_js.add1 = "function (x) { return x + 1; }"
      >>> db.system.js.find({"_id": "add1"}).count()
      1
      >>> db.system_js.add1(5)
      6.0
      >>> del db.system_js.add1
      >>> db.system.js.find({"_id": "add1"}).count()
      0

  Note

  Requires server version >= 1.1.1

  New in version 1.5.

  `list`()

    Get a list of the names of the functions stored in this database.

    New in version 1.9.