db.getSiblingDB()
Definition
ParameterTypeDescriptiondatabase
stringThe name of a MongoDB database.
Returns:A database object.
Used to return another database without modifying thedb
variable in the shell environment.
Example
You can use db.getSiblingDB()
as an alternative to the use<database>
helper. This is particularly useful when writing scriptsusing the mongo
shell where the use
helper is notavailable. Consider the following sequence of operations:
- db = db.getSiblingDB('users')
- db.active.count()
This operation sets the db
object to point to the database namedusers
, and then returns a count of the collection namedactive
. You can create multiple db
objects, that refer todifferent databases, as in the following sequence of operations:
- users = db.getSiblingDB('users')
- records = db.getSiblingDB('records')
- users.active.count()
- users.active.findOne()
- records.requests.count()
- records.requests.findOne()
This operation creates two db
objects referring to differentdatabases (i.e. users
and records
) and then returns acount and anexample document fromone collection in that database (i.e. active
and requests
respectively.)