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• Definition
• Additional Information

Definition

db.collection. ensureIndex ( keys, options )

Deprecated since version 3.0.0: db.collection.ensureIndex() is now an alias for db.collection.createIndex().

Creates an index on the specified field if the index does not already exist.

Additional Information

• Use db.collection.createIndex() rather than db.collection.ensureIndex() to create new indexes.
• The Indexes section of this manual for full documentation of indexes and indexing in MongoDB.
• db.collection.getIndexes() to view the specifications of existing indexes for a collection.