Redis Cookbook

Chapter 3. Leveraging Redis

In this chapter, we’ll look into how we can leverage Redis’s data structures, speed, and flexibility to create complex systems and functionality, typically in a fraction of the time we’d spend doing the same with a RDBMS. We’ll start by looking at ways to store simple data sets, and work up from there in terms of complexity and interest.

Using Redis as a Key/Value Store

Problem

Most applications need to store temporary data about usage, configuration, or other relevant information that might not be a great fit for the fixed structure of relational databases. Traditionally, developers have resorted to hacking a table structure to accommodate this data and using MySQL or another RDBMS to store it. In this recipe, we’ll look at how we can use Redis and its built-in data types to store application data in a lighter, faster, and looser manner.

Solution

Redis positions itself not simply as a key/value store but as a server for data structures as well. This means that on top of typical key/value store functionality, it gives you several ways to store and manipulate application data. We’ll use these structures and commands to store application sample data: as examples, we’ll store usage counters in regular keys, user objects in Redis hashes, and a circle-of-friend implementation (like Google+) using sets.

Discussion

Storing application usage counters

Let’s begin by storing something quite basic: counters. Imagine we run a business social network and want to track profile/page ...