Welcome back! In this lesson, we will explore a crucial feature of Redis: key expiration. This topic builds on our Redis knowledge and adds another tool to our kit for managing data efficiently in high-performance applications.

You will learn how to set expiration times on your Redis keys. This is useful for many situations, such as caching data, managing session lifetimes, or any scenario where you want data to automatically expire after a certain period. We will learn how to set expiration times on keys and check the remaining time-to-live (TTL) for a key.

Here's a quick preview of what you will be doing:

To set a key with an expiration time, you can use the set method with the EX parameter:

The above code snippet shows how to set a key (session:12345) with a value (data) that expires after 2 seconds.

To check the remaining time-to-live (TTL) for a key, you can use the ttl method with the key name as the parameter.