# `dbref` – Tools for manipulating DBRefs (references to documents stored in MongoDB)

Tools for manipulating DBRefs (references to MongoDB documents).

class bson.dbref.DBRef(collection, id, database=None, _extra=None, **kwargs)

  Initialize a new `DBRef`.

  Raises `TypeError` if collection or database is not an instance of `str`. database is optional and allows references to documents to work across databases. Any additional keyword arguments will create additional fields in the resultant embedded document.

  Parameters:

    - collection (str) – name of the collection the document is stored in

    - id (Any) – the value of the document’s `"_id"` field

    - database (Optional[str]) – name of the database to reference

    - kwargs (Any) – additional keyword arguments will create additional, custom fields

    - _extra (Optional[Mapping[str, Any]])

  See also

  The MongoDB documentation on dbrefs.

  as_doc()

    Get the SON document representation of this DBRef.

    Generally not needed by application developers

    Return type:

      SON[str, Any]

  property collection: str

    Get the name of this DBRef’s collection.

  property database: str | None

    Get the name of this DBRef’s database.

    Returns None if this DBRef doesn’t specify a database.

  property id: Any

    Get this DBRef’s _id.