Hashes

Redis · Reference cheat sheet

📋 Overview

Hashes map field → value under one key. Ideal for objects (user profiles, config bags) without serializing a whole JSON blob for every field update.

🔧 Core concepts

💡 Examples

User object:

HSET user:42 name Ada email ada@example.com
HGET user:42 email
HGETALL user:42

Increment field:

HINCRBY user:42 login_count 1

Delete field:

HDEL user:42 email

⚠️ Pitfalls

• HGETALL on huge hashes is expensive — prefer HSCAN.
• Nested structures aren't native — store JSON in a field or use separate keys.
• TTL is on the whole hash key, not per field.

🔗 Related

• strings.md
• lists_sets.md
• expiry_ttl.md
• getting_started.md