Mongo.getDBNames()
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Description
Mongo.getDBNames()
Returns a list of available databases.
Mongo.getDBNames()
calls thelistDatabases
command.The
Mongo.getDBNames()
method doesn't take any parameters.
Compatibility
This method is available in deployments hosted in the following environments:
MongoDB Atlas: The fully managed service for MongoDB deployments in the cloud
MongoDB Enterprise: The subscription-based, self-managed version of MongoDB
MongoDB Community: The source-available, free-to-use, and self-managed version of MongoDB
Examples
List Databases
List the available databases for the current MongoDB instance:
db.getMongo().getDBNames()
The db.getMongo()
method creates a connection to the
instance. Mongo.getDBNames()
returns:
[ 'admin', 'config', 'local', 'test' ]
Map Database List to Another Method
Use Mongo.getDBNames()
to get a list of collections:
db.getMongo().getDBNames().map( name => db.getSiblingDB( name ).getCollectionNames() )
Example output:
[ [ 'system.users', 'system.keys', 'system.version' ], [ 'settings', 'tenantMigrationRecipients', 'system.sessions', 'transactions', 'external_validation_keys', 'image_collection', 'tenantMigrationDonors', 'system.indexBuilds' ], [ 'replset.minvalid', 'system.views', 'oplog.rs', 'replset.initialSyncId', 'startup_log', 'system.replset', 'system.rollback.id', 'replset.oplogTruncateAfterPoint', 'replset.election', 'system.tenantMigration.oplogView' ], [ 'feedback', 'inventory', 'engineers', 'clothes' ] ]
Mongo.getDBNames()
returns a list of databases.map
defines a function that iterates over the list of databases. Each iteration ofmap
:assigns a database to the
name
variable,connects to the database currently stored in
name
usingdb.getSiblingDB()
,returns the collections in the current database using
db.getCollectionNames()
.