One of the interesting features in Mongo is automatically expiring data in the collection after a predetermined amount of time. This is a very useful tool when we want to purge some data older than a particular timeframe. For a relational database, it is not common for folks to set up a batch job that runs every night to perform this operation.
With the TTL feature of Mongo, you need not worry about this as the database takes care of it out of the box. Let's see how we can achieve this.
Let's create data in Mongo that we want to play with using the TTL indexes. We will create a collection called ttlTest
for this purpose. We will require a server to be up and running. Refer to the Installing single node MongoDB recipe from Chapter 1, Installing and Starting the Server for instructions on how to start the server. Start the shell with the TTLData.js
script loaded. This script is available on the Packt website for download...