Book Image

Mastering Redis

By : Vidyasagar N V, Jeremy Nelson
Book Image

Mastering Redis

By: Vidyasagar N V, Jeremy Nelson

Overview of this book

Redis is the most popular, open-source, key value data structure server that provides a wide range of capabilities on which multiple platforms can be be built. Its fast and flexible data structures give your existing applications an edge in the development environment. This book is a practical guide which aims to help you deep dive into the world of Redis data structure to exploit its excellent features. We start our journey by understanding the need of Redis in brief, followed by an explanation of Advanced key management. Next, you will learn about design patterns, best practices for using Redis in DevOps environment and Docker containerization paradigm in detail. After this, you will understand the concept of scaling with Redis cluster and Redis Sentinel , followed by a through explanation of incorporating Redis with NoSQL technologies such as Elasticsearch and MongoDB. At the end of this section, you will be able to develop competent applications using these technologies. You will then explore the message queuing and task management features of Redis and will be able to implement them in your applications. Finally, you will learn how Redis can be used to build real-time data analytic dashboards, for different disparate data streams.
Table of Contents (18 chapters)
Mastering Redis
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Sorted sets


In Redis, the sorted-set data type combines the characteristics of both Redis lists and sets. Similarly to those of a Redis list, a sorted set's values are ordered, and like a set, each value is assured to be unique. Of all the various data structures in Redis, the sorted set is the closest to a killer feature. The flexibility of a sorted set allows for multiple types of access patterns depending on the needs of the application. Using a single sorted set for a player's scores in a game both the top and the bottom players are easily fetched for a leaderboard by either the ZRANGE or ZREVRANGE Redis commands.

For sorted sets, the ZADD command adds a member with a score to the sorted set. The time complexity of ZADD is O(log(n)), meaning that as the size of the sorted set increases, the rate of increase in the processing time is a constant. Therefore, the difference between adding a new member to a large sorted set is trivial; the difference between log(10000) ~ 9.21034037 and log...