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- System Collections
System Collections¶
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Synopsis¶
MongoDB stores system information in collections that use the
<database>.system.*
namespace, which MongoDB reserves for
internal use. Do not create collections that begin with system
.
MongoDB also stores some additional instance-local metadata in the local database, specifically for replication purposes.
Collections¶
System collections include these collections stored directly in the database:
-
<database>.system.
namespaces
¶ The
<database>.system.namespaces
collection contains information about all of the database’s collections. Additional namespace metadata exists in thedatabase.ns
files and is opaque to database users.
-
<database>.system.
indexes
¶ The
<database>.system.indexes
collection lists all the indexes in the database. Add and remove data from this collection via theensureIndex()
anddropIndex()
-
<database>.system.
profile
¶ The
<database>.system.profile
collection stores database profiling information. For information on profiling, see Database Profiling.
-
<database>.system.
users
¶ The
<database>.system.users
collection stores credentials for users who have access to the database. For more information on this collection, see Authentication.
-
<database>.system.
js
¶ The
<database>.system.js
collection holds special JavaScript code for use in server side JavaScript. See Storing Functions Server-side for more information.