Redis: The Ultimate In-Memory Data Store

Redis, the ultimate in-memory data store, has been a game-changer for developers looking to build powerful applications and services. In this beginner-friendly guide, we’ll cover how to setup Redis locally or with Docker, work with core data structures (strings, hashes, lists, sets, sorted sets), and leverage its various features for real-time apps, queues, leaderboards, and more.

1. Start Redis Locally or with Docker

To start Redis locally or with Docker, follow these steps:

• Install Redis on your local machine or docker host:
• Set up the Redis server using the `redis-server` command:
• Run the Redis Docker container:
• Connect to the Redis container using the Redis CLI:
• Test the connection using the `PING` command:
• Install the Redis Docker image:
• Start the Redis container using the `docker run` command:
• Open the Redis Docker CLI:

Redis is more than just a cache—it’s a powerful in-memory data store that supports real-time apps, queues, leaderboards, and more.

In this beginner-friendly guide, we’ll cover how to:
✅ Set up Redis locally or with Docker
✅ Use Redis CLI for quick testing
✅ Work with core data structures (Strings, Hashes, Lists, Sets, Sorted Sets)

🚀 Setup & Basics
Start Redis

Start Redis (local)


redis-server

Run with Docker
docker run --name redis -p 6379:6379 -d redis

Open Redis CLI
redis-cli

Test Connection

PING
# PONG

📦 Core Data Structures
🔹 Strings

SET name "Asad"
GET name
INCR counter

Use cases: counters, sessions, caching simple values.

Diagram:

key    →   value
----------------
name   →   "Asad"
counter →   1

🔹 Hashes

HSET user:1 name "Asad" age "25"
HGETALL user:1

Use cases: store JSON-like objects (e.g., user profiles).

Diagram:

user:1
 ├── name → "Asad"
 └── age  → "25"

🔹 Lists

LPUSH tasks "task1"
RPUSH tasks "task2"
LPOP tasks

Use cases: queues (FIFO), stacks (LIFO).

Diagram (FIFO Queue):

[ task1 ] → [ task2 ] → [ task3 ]

🔹 Sets
SADD tags “redis” “database” “cache”
SMEMBERS tags

Use cases: unique collections (tags, categories, followers).

Diagram:

tags = { “redis”, “database”, “cache” }

🔹 Sorted Sets
ZADD scores 100 “Asad” 200 “Plabon”
ZRANGE scores 0 -1 WITHSCORES

Use cases: leaderboards, rankings, priority queues.

Diagram:

+——+———+
|User | Score |
+——+———+
|Asad | 100 |
|Plabon| 200 |

✅ Wrap-Up

That’s the foundation of Redis. With just a few commands, you can build counters, queues, and ranking systems.

👉 In the next article, we’ll go deeper into advanced Redis concepts like Pub/Sub, Streams, persistence, clustering, and real-world AI use cases.