Welcome to the first step in building our Redis-based backend system. In this unit, we will focus on how to manage user data with expiration using Redis in PHP. This is a fundamental part of our project that will set the stage for more advanced features in later units.

In this unit, we will implement two primary operations for managing user data using PHP:

1. Adding user data with an expiration time: This ensures that user data is stored only for a specified duration before being automatically deleted.
2. Retrieving user data: This allows us to fetch the stored user data.

Here is a PHP code example to help illustrate these operations:

In this example, set is used to store user data, and expire is used to set the expiration time, which is specified as 24 * 60 * 60 to represent a duration of one day in seconds. The get method is used to retrieve the stored data.

The expire method is called separately from set because, by default, does not automatically associate an expiration time with the key. If you want to set a key with an expiration in one step, you can use , which both stores the value and sets an expiration time: