OBJECT ENCODING for internal encoding in Redis

Introduction

Redis uses internal object encoding to store data efficiently and quickly.

When you want Redis to save memory by storing data in a compact way.

When Redis needs to speed up data access by choosing the best format.

When you want to understand how Redis stores your keys internally.

When debugging Redis performance or memory usage.

When optimizing Redis for specific data types like strings or lists.

Syntax

Redis

OBJECT ENCODING <key>

This command shows how Redis stores the value of the given key internally.

The encoding depends on the data type and size of the value.

Examples

Stores a simple string and checks its internal encoding.

Redis

SET mykey hello
OBJECT ENCODING mykey

Creates a list and shows how Redis encodes it internally.

Redis

LPUSH mylist a b c
OBJECT ENCODING mylist

Creates a hash and checks its internal encoding.

Redis

HSET myhash field1 value1
OBJECT ENCODING myhash

Sample Program

This example sets a string key and then shows how Redis stores it internally.

Redis

SET greeting Hello
OBJECT ENCODING greeting

Important Notes

Common encodings for strings are raw and embstr.

Lists are encoded as quicklist.

Understanding encoding helps optimize Redis memory and speed.

Summary

Redis uses different internal encodings to store data efficiently.

The OBJECT ENCODING command reveals how a key is stored inside Redis.

Knowing encoding helps with performance and memory optimization.