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- Index Properties
Index Properties¶
In addition to the numerous index types MongoDB supports, indexes can also have various properties. The following documents detail the index properties that you can select when building an index.
- TTL Indexes
- The TTL index is used for TTL collections, which expire data after a period of time.
- Unique Indexes
- A unique index causes MongoDB to reject all documents that contain a duplicate value for the indexed field.
- Sparse Indexes
- A sparse index does not index documents that do not have the indexed field.