Activating MongoDB TTL for indexes

mongo_ttl_indexes

- Creating new index with ttl, the key must be date type and can not be a compound index.

> db.teste_ttl_idx.ensureIndex({ttl: 1}, {expireAfterSeconds: 5});

- Insert new documents
> db.teste_ttl_idx.insert({ttl: new Date()});
> db.teste_ttl_idx.insert({ttl: new Date()});
> db.teste_ttl_idx.insert({ttl: new Date()});

- You can do a find all to check if the elements were inserted and if they will be removed in the next 5 seconds after their creation.
> db.teste_ttl_idx.find();

Note:
- TTL indexes expire data by removing documents in a background task that runs every 60 seconds. As a result, the TTL index provides no guarantees that expired documents will not exist in the collection. Consider that:
Documents may remain in a collection after they expire and before the background process runs.
The duration of the removal operations depend on the workload of your mongod instance.