redis.md

#redis cheatsheet

###key - value

1. SET key_name value

2. GET key_name value

###increment number

1.INCR key_name

is it equivalent to

x = GET count
x = x + 1
SET count x

??? no, INCR ensure that it is an atomic operation

life time of key

EXPIRE key seconds

TTL key

time to live

• -1 : never die
• -2 : not exist

data structures

list

• RPUSH,LPUSH key value
• LRANGE key start end
  • 0 -1 : show all
  • 0 1 : index 0 to 1
• LLEN key
• LPOP,RPOP key

set

• SADD key value
• SREM key value: removes value
• SISMEMBER key value
• SMEMBERS key : show all keys in the set
• SUNION key1 key2 ... : keys of combined set (duplication key only show one time)

sorted set

• ZADD key value
• ZRANGE key start end

hashes

• HSET hashname key value
• HGETALL hashname
• HMSET hashname key1 value1 key2 value2 ...
• HGET hashname key
• HINCRBY hashname key incr_value: ex) HINCRBY user:1000 visits 1 => incr 1
• HDEL hashname key

more hash commands: here

redis documentation here