Redis is an open-source, in-memory data structure store used as a:
- Database
- Cache
- Message Broker
- Streaming engine
Installation on Linux - Ubuntu
sudo apt-get update
sudo apt-get install redis-server
Start redis-server as daemon
redis-server --daemonize yes
Redis Data Types
Strings
- stores redis key with a value of type sequences of bytes, including text, serialized objects, and binary arrays
- often used for caching but also support increments and bitwise operations
Commands
| command | description |
|---|---|
KEYS * | get all keys |
SET | stores a string value |
SETNX | stores a string value if key doesn’y already exists, useful for implementing locks |
GET | retrieves a string value |
MSET | set multiple string values |
MGET | retrieve multiple string values |
INCRBY | atomically increments counters stored at a given key |
INCRBYFLOAT | atomic increment for floating point numbers |
JSON
- sets a redis key with a JSON value