Welcome back! We're moving on to the next essential part of our Redis-based backend system project — handling transactions with pipelines. This will help us execute multiple Redis commands as a single atomic operation. Remember, you've already gotten comfortable with managing user data and leaderboards. This unit will take it a step further by optimizing these operations using pipelines.

Before we dive in, let's recap what you’ll be focusing on in this unit. The key tasks include:

1. Adding user data with expiration using pipelines: We will group multiple commands into one pipeline to add user data more efficiently.
2. Adding scores to a leaderboard using pipelines: Using pipelines to add scores will ensure these operations are atomically executed.
3. Executing the pipeline: We'll ensure the grouped commands in the pipeline are executed together.

These tasks will help us understand how pipelines can enhance performance and consistency in our Redis operations.

Here's a snippet to remind you of how pipelines work:

This way, all commands in the pipeline are sent to the Redis server in one batch when pipeline.exec() is called. This ensures that the commands are executed atomically.