General commands

Set a new key

SET server:name = "fido"

Get a key value

GET server:name

Check if a key exists

EXISTS server:name

Detete a given key

DEL server:name

Increment & Decrement a given key value

SET connections 10
INCR connections
DECR connections

Increment & Decrement by a specific value

INCRBY connections 100
DECRBY connctions 10

Expire Value and TTL

Seting time limit

SET key = 10
EXPIRE key 100 
PEXPIRE key 100000

Here, EXPIRE calculates in second PEXPIRE calculates in milisecond

We can also define expire time at the time of declaration

SET key "Hello World" EX 5

View current time limit

TTL key
PTTL key

TTL shows timelimit in second PTTL shows timelimit in milisecond

Cancel timelimit

PERSIST key

List Commands

RPUSH, LPUSH, LLEN, LRANGE, LPOP, and RPOP

Description

RPUSH Pushes an item/ items to the end of the list

LPUSH Pushes an item/ items to the start of the list

RPUSH friends "Liam"
RPUSH friends "Steve" "Diponkor" "Mahim"
LPUSH friends "Rafi"
RPUSH friends "Abid" "Samin" "Joyanta"

LRANGE Retrive items from a list in specific range 0 is starting index and if we count from last -1 is the first index, -2 is the second index and so one. Example. lists all friends

lrange friends 0 -1

LPOP Removes the first element from the list

RPOP Removes the last element from the list

LLEN Gets the length of the list

Set Commands

SADD, SREM, SISMEMBER, SMEMBERS, SUNION

SADD add an item/ items to set

SREM remove an item/ items from set

SISMEMBER check if an items exists

SUNION Returns the union of two sets

SUNION set1 set2

SPOP removes and return single or specific number of item from last

Removing on item from last
SPOP friends
Removing specific number of items from the list
SPOP friends 3

Sorted sets

All commands and working priniciple are same to sets but each element has a score which is used to short the set items

ZADD, ZRANGE

ZADD hackers 1940 "Alan Kay"
ZADD hackers 1906 "Grace Hopper"
ZADD hackers 1953 "Richard Stallman"
ZADD hackers 1965 "Yukihiro Matsumoto"
ZADD hackers 1916 "Claude Shannon"
ZADD hackers 1969 "Linus Torvalds"
ZADD hackers 1957 "Sophie Wilson"
ZADD hackers 1912 "Alan Turing"

Hash field

HSET user:1000 visits 10
HINCRBY user:1000 visits 1 => 11
HINCRBY user:1000 visits 10 => 21
HDEL user:1000 visits
HINCRBY user:1000 visits 1 => 1