"MongoDB Learning Note 27" MongoDB TTL index

The TTL index (time-to-live index) allows you to set a time-out for each document, which is deleted when the document exceeds that time.

You can create a TTL index by specifying the EXPIREAFTERSECS option in Ensureindex:

>db.foo.ensureindex ({"lastupdated": 1},{"Expireaftersecs": 60*60*24})

The above command creates a TTL index on the lastupdated field for the set Foo, and if the document's LastUpdated field is a date type, the document is deleted when the server is 24 hours behind the time in the LastUpdated field of the document.

When the TTL is established, you can use the Collmod command to modify the TTL index time-out:

>db.runcommand ({"Collmod": "IndexName", "lastupdated": 3600)

This article is from the "Margin with Wish" blog, please be sure to keep this source http://281816327.blog.51cto.com/907015/1601637

"MongoDB Learning Note 27" MongoDB TTL index