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reIndex¶
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reIndex
¶ The
reIndex
command 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
Use the following syntax:
The command takes the following fields:
Field Description reIndex The name of the collection to reindex. The
mongo
shell provides a wrapperdb.collection.reIndex()
.
Behavior¶
Note
For replica sets, reIndex
will not propagate from the
primary to secondaries. reIndex
will
only affect a single mongod
instance.
Important
Starting in MongoDB 4.0, reIndex
takes a global
exclusive (W) lock
and blocks other operations on the
database and all its collections until it finishes.
See
Index Builds on Populated Collections for more information on the behavior of indexing operations in MongoDB.