Redis is a very popular, memory-based, lightweight key-value database. Strictly speaking, Redis is a data structure server, according to Matt Stancliff (@mattsta), one of the most important contributors to Redis (https://matt.sh/thinking-in-redis-part-one). The author of Redis, Salvatore Sanfilippo (@Antirez), first called it Redis, which stands for REmote DIctionary Server because Redis natively implements various kinds of data structures in memory, and provides a variety of APIs for manipulating these data structures. More importantly, Redis supports high-performance command processing, high availability/scalability architectures, and also data persistence features as a long running data store service.
With the development of high-concurrency and low-latency systems, the use of Redis is becoming more and more widespread. Redis has been ranked in the top ten of the DB-Engine complete ranking (https://db-engines.com/en/ranking) since 2017. Before that, it was ranked at the top of the key-value stores ranking (https://db-engines.com/en/ranking/key-value+store) for quite a long time.
The goal of this chapter is to guide readers to quickly set up a simple Redis instance and learn about some common operations, such as starting, connecting, and shutting down a Redis Server. Retrieving basic information from a Redis Server is also introduced. Moreover, it's essential to have a better understanding of the event model and communication protocol of Redis before learning Redis. The last two sections of this chapter include a detailed discussion of the event model and protocol of Redis.
