Redis -- data type and operation

Remote connection

redis-cli -h host -p port -a password

#  Chinese garbled 
--raw

Basic data type

string

• String

#  establish key
> set name zhangsan
OK
#  obtain key
> get name
"zhangsan"
#  Set multiple items and get multiple items at the same time 
> set name zhangsan 
> set age 18
> mset city wuhan country China
> mget name age city country
1) "zhangsan"
2) "18"
3) "wuhan"
4) "China"

#  Delete key
> del name
(integer) 1
> get name
(nil)

#  Check for presence 
> exists name
(integer) 1
> exists age
(integer) 0

• Numeric String

> set n 11
OK
> get n
"11"
#  Add one... In turn 
> incr n 
(integer) 12
#  One in turn 
> decr n 
(integer) 11
#  Gat fixed value 
> incrby n 10
(integer) 14
#  Subtract a specific value 
> decrby n 10
(integer) 4

set

string Unordered collection of type , The bottom is HashTable data structure ,
String elements are unordered , And can't repeat

#  add to 
> sadd friends zhangsan
(integer) 1
> sadd friends lisi
(integer) 1
#  see 
> smembers friends
1) "lisi"
2) "zhangsan"
#  Remove the specified value 
> srem friends lisi
#  Random delete 
> spop friends
"zhangsan"
#  Determine whether an element exists 
> sismember friends zhangsan
(integer) 1

zset

#  add to 
> zadd country 1 China
(integer) 1
> zadd country 1 UK
(integer) 1
#  see 
> zrange country 0 -1
1) "China"
2) "UK"
> zrange country 0 -1 withscores
1) "China"
2) "1"
3) "UK"
4) "1"
#  Remove the specified value 
> zrem country UK
(integer) 1

List

#  Insert from the left 
> lpush rlist zhangsan lisi
(integer) 2
> lpush rlist wangwu
(integer) 3

#  Insert from the right 
> rpush rlist chenliu
(integer) 4


#  see 
> lrange rlist 0 -1
1) "wangwu"
2) "lisi"
3) "zhangsan"
4) "chenliu"

#  Delete from the left 
> lpop rlist 
"wangwu"
#  Delete from the left 
> rpop rlist 
"chenliu"
> lrange rlist 0 -1
1) "lisi"
2) "zhangsan"

#  The view index is 1 Of key value 
> lindex rlist 1
"zhangsan"
#  Change the index to 1 Of key value 
> lset rlist 1 lili
OK
> lrange rlist 0 -1
1) "lisi"
2) "lili"

Hash

Be similar to Java Medium Map, It's a String Type of field and value Mapping table ( Key value pair set ), And it is especially suitable for storing objects

# hset 
> hmset user name zhangsan age 18 sex male
OK

# hget
> hget user name
"zhangsan"

# hmget
> hmget user name
1) "zhangsan"

#  Check all values 
hkeys user
1) "name"
2) "age"
3) "sex"
4) "height"

#  modify 
> hset user height 145
(integer) 0
> hmget user height
1) "145"

• Expiration time

• expire: Set expiration time
• ttl： Get expiration time , return -1 Indicates no settings ,-2 Indicates that the data does not exist

> set name zhangsan
OK
> expire name 20
(integer) 1
> ttl name
(integer) 4
> ttl name
(integer) -2