Redis Basics

Introduction

Redis is an in-memory data structure store used as database, cache, and message broker.

Basic Operations

import redis

r = redis.Redis(host="localhost", port=6379, db=0)

# String operations
r.set("key", "value")
r.get("key")
r.setex("key", 3600, "value")  # With expiry
r.incr("counter")
r.decr("counter")

# Multiple operations
r.mset({"a": 1, "b": 2})
r.mget(["a", "b"])

Hash Operations

# Hash fields
r.hset("user:1", mapping={"name": "Alice", "email": "alice@email.com"})
r.hget("user:1", "name")
r.hgetall("user:1")
r.hincrby("user:1", "visits", 1)

List Operations

# Lists
r.lpush("queue", "task1")
r.rpush("queue", "task2")
r.lpop("queue")
r.lrange("queue", 0, -1)  # All items
r.llen("queue")

Practice Problems

1. Use Redis as cache
2. Store session data
3. Implement rate limiting
4. Use lists as queues
5. Manage cache expiration