Key-Value

Features

• Databases structured almost like JSON or Python dictionaries.

• Each key is unique.

• Data stored in memory, not disk, so it's extremely fast.

• Simplest way to use a database (3 commands: set, get & delete).

Uses

• Real-time data delivery.

• Cache on top of some other persistent data (like messages, gaming leaderboard, ...)

Databases

• Redis

• MEMcached

Companies that use it

• Apple

• Twitter

• GitHub

• Snapchat