db.collection.unhideIndex()
Definition
db.collection.unhideIndex()
Important
mongosh Method
This page documents a
mongosh
method. This is not the documentation for database commands or language-specific drivers, such as Node.js.For the database command, see the
index.hidden
collection option set using thecollMod
command.For MongoDB API drivers, refer to the language-specific MongoDB driver documentation.
Unhides an existing index from the query planner. Once unhidden, the indexes are immediately available for use.
Compatibility
This method 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, see Unsupported 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
Syntax
db.collection.unhideIndex(<index>)
Parameters
The db.collection.unhideIndex()
method takes the following
parameter:
Parameter | Type | Description |
---|---|---|
| string or document | Specifies the index to unhide from the query planner. You can specify the index either by the index name or by the index specification document. TipYou can use the To unhide a text index, specify the index name. |
The db.collection.unhideIndex()
is a mongosh
shell
wrapper for the collMod
command.
Behavior
Index Modifications Reset Statistics
Unhiding a hidden index resets its $indexStats
.
No-op
Unhiding an already unhidden index has no effect on the index. However, the operation will still generate an empty oplog entry.
Required Access
If the deployment enforces authentication/authorization, you must have
the collMod
privilege in the collection's database.
The built-in role dbAdmin
provides the required privileges.
Example
The following example unhides an existing index.
First, use db.collection.createIndex()
to create a hidden
index:
db.restaurants.createIndex( { borough: 1, ratings: 1 }, { hidden: true } );
To verify, run db.collection.getIndexes()
on the
restaurants
collection:
db.restaurants.getIndexes();
The operation returns the following information:
[ { "v" : 2, "key" : { "_id" : 1 }, "name" : "_id_" }, { "v" : 2, "key" : { "borough" : 1, "ratings" : 1 }, "name" : "borough_1_ratings_1", "hidden" : true } ]
The index option hidden
is only returned if the value is true
.
To unhide the index, you can specify either the index key specification
document or the index name to the db.collection.unhideIndex()
method. The following specifies the index name:
db.restaurants.unhideIndex( "borough_1_ratings_1" );
To verify, run db.collection.getIndexes()
on the
restaurants
collection:
db.restaurants.getIndexes()
The operation returns the following information:
[ { "v" : 2, "key" : { "_id" : 1 }, "name" : "_id_" }, { "v" : 2, "key" : { "borough" : 1, "ratings" : 1 }, "name" : "borough_1_ratings_1" } ]
The index option hidden
no longer appears as part of the
borough_1_ratings_1
index since the field is only returned if the
value is true
.