listDatabases (original) (raw)

listDatabases

The listDatabases command returns an unsorted list of all existing databases and basic statistics about each database. You must run the listDatabases command against the admin database.

This command is available in deployments hosted in the following environments:

MongoDB Atlas: The fully managed service for MongoDB deployments in the cloud

Note

This command is supported in all MongoDB Atlas clusters. For information on Atlas support for all commands, seeUnsupported Commands.

MongoDB Enterprise: The subscription-based, self-managed version of MongoDB
MongoDB Community: The source-available, free-to-use, and self-managed version of MongoDB


db.adminCommand(

   {

     listDatabases: 1

   }

)

The value (e.g. 1) does not affect the output of the command.

The command can take the following optional fields:

Field	Type	Description
filter	document	Optional. A query predicate that determines which databases are listed.You can specify a condition on any of the fields in the output oflistDatabases:namesizeOnDiskemptyshards
nameOnly	boolean	Optional. A flag to indicate whether the command should return just the database names, or return both database names and size information.The default value is false, so listDatabases returns the name and size information of each database.
authorizedDatabases	boolean	Optional. A flag that determines which databases are returned based on the user privileges when access control is enabled.If authorizedDatabases is unspecified, andIf the user has listDatabases action on the cluster resource, listDatabases command returns all databases.If the user does not have listDatabases action on the cluster, listDatabases returns only the databases for which the user has privileges (including databases for which the user has privileges on specific collections).If authorizedDatabases is true, listDatabases returns only the databases for which the user has privileges (including databases for which the user has privileges on specific collections).If authorizedDatabases is false, andIf the user has listDatabases action on the cluster, listDatabases command returns all databasesIf the user does not have listDatabases action on the cluster, listDatabases command errors with insufficient permissions.For more information, see Behavior.
comment	any	Optional. A user-provided comment to attach to this command. Once set, this comment appears alongside records of this command in the following locations:mongod log messages, in theattr.command.cursor.comment field.Database profiler output, in the command.comment field.currentOp output, in the command.comment field.A comment can be any valid BSON type(string, integer, object, array, etc).

When authentication is enabled, the listDatabases command returns different values based on the privileges assigned to the user who executes the command and theauthorizedDatabases command option:

If authorizedDatabases is unspecified, and
- If the user has listDatabases action on the cluster resource, listDatabases command returns all databases.
- If the user does not have listDatabases action on the cluster, listDatabases command returns only the databases for which the user has privileges (including databases for which the user has privileges on specific collections).
If authorizedDatabases is true, listDatabasescommand returns only the databases for which the user has privileges (including databases for which the user has privileges on specific collections).
If authorizedDatabases is false, and
- If the user has listDatabases action on the cluster, listDatabases command returns all databases
- If the user does not have listDatabases action on the cluster, listDatabases command errors with insufficient permissions.

Starting in MongoDB 4.2, if the client that issued listDatabasesdisconnects before the operation completes, MongoDB marks listDatabasesfor termination using killOp.

To run on a replica set member, listDatabases operations require the member to be in PRIMARY or SECONDARY state. If the member is in another state, such as STARTUP2, the operation errors.

Run listDatabases against the admin database:


db.adminCommand( { listDatabases: 1 } )

Example output:


{

   "databases" : [

      {

         "name" : "admin",

         "sizeOnDisk" : 83886080,

         "empty" : false

      },

      {

         "name" : "local",

         "sizeOnDisk" : 83886080,

         "empty" : false

      },

      {

         "name" : "test",

         "sizeOnDisk" : 83886080,

         "empty" : false

      }

   ],

   "totalSize" : 251658240,

   "totalSizeMb" : 251,

   "ok" : 1

}

Run listDatabases against the admin database. Specify the nameOnly: true option:


db.adminCommand( { listDatabases: 1, nameOnly: true} )

Example output:


{

   "databases" : [

      {

         "name" : "admin"

      },

      {

         "name" : "local"

      },

      {

         "name" : "test"

      }

   ],

   "ok" : 1

}

Run listDatabases against the admin database. Specify the filter option to only list databases that match the specified filter criteria.

For example, the following specifies a filter such thatlistDatabases only returns information on databases whose name matches the specified regular expression:


db.adminCommand( { listDatabases: 1, filter: { "name": /^rep/ } } )

When executed against a mongos instance,listDatabases:

adds a shards embedded document to each database's summary document if nameOnly: false, and
excludes the local database.

Each element in the shards embedded document consists of a field whose key gives the name of a collection on that shard, and whose value represents the collection's size in bytes.

The sizeOnDisk field represents the total size of all listed collections and indexes.

For example:


{

  "databases" : [

    {

      "name" : "admin",

      "sizeOnDisk" : 16384,

      "empty" : false,

      "shards" : {

        "config" : 16384

      }

    },

    {

      "name" : "config",

      "sizeOnDisk" : 176128,

      "empty" : false,

      "shards" : {

        "clients" : 28672,

        "patients" : 8192,

        "config" : 139264

      }

    },

    {

      "name" : "test",

      "sizeOnDisk" : 12288,

      "empty" : false,

      "shards" : {

        "clients" : 12288

      }

    }

  ],

  "totalSize" : 204800,

  "totalSizeMb" : 0,

  "ok" : 1

}