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db.getSiblingDB()

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Definition

db.getSiblingDB(<database>)
ParameterTypeDescription
databasestringThe name of a MongoDB database.
Returns:A database object.

Used to return another database without modifying the db 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 scripts using mongosh where the use helper is not available.

Consider a MongoDB instance with two databases, users and records. The active collection is a part of the users database. The requests collection is a part of the records database.

Specify a Database

This operation sets the db object to point to the database named users, and then returns a document count for the active collection.

db = db.getSiblingDB('users')
db.active.countDocuments()

Use Multiple Databases

You can create multiple db objects, that refer to different databases, as in the following sequence of operations:

users = db.getSiblingDB('users')
records = db.getSiblingDB('records')


users.active.countDocuments()
users.active.findOne()


records.requests.countDocuments()
records.requests.findOne()

This operation creates two db objects. Each db object refers to a different database, users or records.

For each database, the query returns:

from a collection in that database.