reIndex
On this page
Definition
reIndexThe
reIndexcommand drops all indexes on a collection and recreates them. This operation may be expensive for collections that have a large amount of data and/or a large number of indexes.Warning
reIndexmay only be run on standalone instances.For most users, the
reIndexcommand is unnecessary.
Use the following syntax:
{ reIndex: <collection> } The command takes the following fields:
FieldDescriptionreIndexThe name of the collection to reindex.mongoshprovides a wrapperdb.collection.reIndex().
Behavior
For MongoDB 5.0 or later, reIndex may only be run on
standalone instances.
Resource Locking
Changed in version 4.2.2.
For MongoDB 4.2.2 and later, reIndex obtains an exclusive
(W) lock on the collection and blocks other operations on the collection
until it completes.
For MongoDB 4.0.0 through 4.2.1, reIndex obtains a global
exclusive (W) lock and blocks other operations on the
mongod until it completes.
For MongoDB 3.6 and earlier, reIndex
obtains an exclusive (W) lock on the database and blocks other
operations on the database until finished.
For more information on locking in MongoDB, see FAQ: Concurrency.
Tip
See:
Index Builds on Populated Collections for more information on the behavior of indexing operations in MongoDB.