Location>code7788 >text

redis - [07] Data Type

Popularity：227 ℃/2025-02-26 00:00:27

redis is an open source (BSD licensed) in-memory data structure storage system that can be used as database, cache and message middleware MQ. It supports multiple types of data structures, such as String, Hash, List, Set, Sorted Sets, Sorted Sets, Bitmaps, hyperloglogs, and geospatial (geospatial) Index radius query. Redis has built-in replication and LUA scripting), LRU-driven events, transactions, and different levels of disk persistence, and provide high availability through Redis Sentinel and automatic partitioning. redis is case-insensitive.

 

000 || redis-key

127.0.0.1:6379> set name harley # Set key
 OK
 127.0.0.1:6379>
 127.0.0.1:6379> keys * # View all keys in the current database
 1) "name"
 127.0.0.1:6379>
 127.0.0.1:6379> exists name # Check whether a key exists
 (integer) 1
 127.0.0.1:6379>
 127.0.0.1:6379> move name 1 # Remove key
 (integer) 1
 127.0.0.1:6379>
 127.0.0.1:6379> keys *
 (empty array)
 127.0.0.1:6379>
 127.0.0.1:6379> set name harley
 OK
 127.0.0.1:6379>
 127.0.0.1:6379> keys *
 1) "name"
 127.0.0.1:6379>
 127.0.0.1:6379> clear # Clear screen
 127.0.0.1:6379> expire name 10 # Set the expiration time of name to 10s
 (integer) 1
 127.0.0.1:6379> ttl name # Check the remaining expiration time of the name
 (integer) 7
 127.0.0.1:6379> ttl name
 (integer) 3
 127.0.0.1:6379> get name # View the value of name
 (nil)
 127.0.0.1:6379> set name harley
 OK
 127.0.0.1:6379> type name # Check the type of key
 string
 127.0.0.1:6379>

Expiration time can be used to set the expiration time setting of cookies

 

 

001 || String

90% of Java programmers use redis to only use one String type

127.0.0.1:6379> set key1 v1 # Set value
 OK
 127.0.0.1:6379> get key1 # Get value
 "v1"
 127.0.0.1:6379> keys * # View all keys
 1) "key1"
 127.0.0.1:6379> exists key1 # determine whether a key exists
 (integer) 1
 127.0.0.1:6379> append key1 "hello" # Append string, if key1 does not exist, it will be created
 (integer) 7
 127.0.0.1:6379> get key1 # View key
 "v1hello"
 127.0.0.1:6379>
 127.0.0.1:6379> STRLEN key1 # Get the length of the string
 (integer) 7
 127.0.0.1:6379> APPEND key1 harley
 (integer) 13
 127.0.0.1:6379> STRLEN key1
 (integer) 13
 127.0.0.1:6379> get key1
 "v1helloharley"
 127.0.0.1:6379>

counter

127.0.0.1:6379>
 127.0.0.1:6379> set views 0 # The initial value is 0
 OK
 127.0.0.1:6379> get views
 "0"
 127.0.0.1:6379> INCR views # Initial 1
 (integer) 1
 127.0.0.1:6379> get views
 "1"
 127.0.0.1:6379> INCR views
 (integer) 2
 127.0.0.1:6379> INCR views
 (integer) 3
 127.0.0.1:6379> get views
 "3"
 127.0.0.1:6379>
 127.0.0.1:6379>
 127.0.0.1:6379> decr views # self-decrease 1
 (integer) 2
 127.0.0.1:6379> decr views
 (integer) 1
 127.0.0.1:6379>
 127.0.0.1:6379> get views
 "1"
 127.0.0.1:6379>
 127.0.0.1:6379> INCRBY views 10 # Step size 10, increase 10 by itself
 (integer) 11
 127.0.0.1:6379>
 127.0.0.1:6379> DECRBY views 5 # Self-decreasing 5
 (integer) 6

String range

127.0.0.1:6379> set key1 "hello,harley" # Set the value of key1
 OK
 127.0.0.1:6379> get key1
 "hello,harley"
 127.0.0.1:6379> GETRANGE key1 0 3 # Intercept string [0,3]
 "hell"
 127.0.0.1:6379> GETRANGE key1 0 -1 # Get all strings equivalent to get key
 "hello,harley"
 127.0.0.1:6379> set key2 abcdefg
 OK
 127.0.0.1:6379> get key2
 "abcdefg"
 127.0.0.1:6379> SETRANGE key2 1 hello # Replace the string starting at the specified position
 (integer) 7
 127.0.0.1:6379> get key2
 "ahellog"
 127.0.0.1:6379>

setex & setnx

127.0.0.1:6379> setex key3 30 "hello" # Set expiration time 30s, set with expire
 OK
 127.0.0.1:6379> ttl key3
 (integer) 27
 127.0.0.1:6379> get key3
 "hello"
 127.0.0.1:6379> setnx mykey "redis" # does not exist (it will be used frequently in distributed locks)
 (integer) 1
 127.0.0.1:6379> ttl key3
 (integer) -2
 127.0.0.1:6379> keys *
 1) "key2"
 2) "mykey"
 3) "key1"
 127.0.0.1:6379> setnx mykey "MongoDB"# If the current key exists, the creation fails and returns 0
 (integer) 0
 127.0.0.1:6379> get mykey
 "redis"
 127.0.0.1:6379>

Set value in batches

127.0.0.1:6379> mset k1 v1 k2 v2 k3 v3 # Batch setting value
 OK
 127.0.0.1:6379> keys *
 1) "k3"
 2) "k1"
 3) "k2"
 127.0.0.1:6379>
 127.0.0.1:6379> mget k1 k2 k3 # Get multiple values
 1) "v1"
 2) "v2"
 3) "v3"
 127.0.0.1:6379> msetnx k1 v1 k4 v4 # is an atomic operation, k1 already exists, so the execution fails
 (integer) 0
 127.0.0.1:6379> keys *
 1) "k3"
 2) "k1"
 3) "k2"
 127.0.0.1:6379>

Object

127.0.0.1:6379> mset user1:1:name zhangsan user1:1:age 18 # Set name and age
 OK
 127.0.0.1:6379> mget user1:1:name user1:1:age # Get value in batches
 1) "zhangsan"
 2) "18"
 127.0.0.1:6379>

getset

127.0.0.1:6379> getset db redis # Return the value of get first, and then set
 (nil)
 127.0.0.1:6379> get db
 "redis"
 127.0.0.1:6379> getset db mongodb # Update operation
 "redis"
 127.0.0.1:6379> get db
 "mongodb"

 

Applicable scenarios

In similar use scenarios, value can be a number in addition to strings.

  • counter
  • Statistics the number of multiple units: uid:572413118:follow 0
  • Number of fans
  • Object storage

 

 

002 || List

Basic data types, list. In redis, list can be used as stack, queue, or blocking queue

You can insert values ​​on both left and right sides of the list at the same time

127.0.0.1:6379> lpush list one # Insert one value or multiple values ​​to the leftmost of the list
 (integer) 1
 127.0.0.1:6379> lpush list two
 (integer) 2
 127.0.0.1:6379> lpush list three
 (integer) 3
 127.0.0.1:6379> lrange list 0 -1 # Get all values ​​of the list
 1) "three"
 2) "two"
 3) "one"
 127.0.0.1:6379> lrange list 0 1
 1) "three"
 2) "two"
 127.0.0.1:6379> lrange list 0 0 # Get the latest inserted value
 1) "three"
 127.0.0.1:6379>
 127.0.0.1:6379> Rpush list four # Insert the value to the rightmost of the list
 (integer) 4
 127.0.0.1:6379> lrange list 0 -1
 1) "three"
 2) "two"
 3) "one"
 4) "four"
 127.0.0.1:6379>
 127.0.0.1:6379> lrange list 0 -1
 1) "three"
 2) "two"
 3) "one"
 4) "four"
 127.0.0.1:6379> Lpop list # Remove the first element of list
 "three"
 127.0.0.1:6379>
 127.0.0.1:6379> Rpop list # Remove the last element of the list
 "four"
 127.0.0.1:6379> lrange list 0 -1
 1) "two"
 2) "one"
 127.0.0.1:6379>
 127.0.0.1:6379> lindex list 1 # Get a certain value in the list by subscript
 "one"
 127.0.0.1:6379> lindex list 0
 "two"
 127.0.0.1:6379>

Get the length of the list

127.0.0.1:6379> Lpush list one
 (integer) 1
 127.0.0.1:6379> Lpush list two
 (integer) 2
 127.0.0.1:6379> Lpush list three
 (integer) 3
 127.0.0.1:6379>
 127.0.0.1:6379> Llen list # Get the value of the list
 (integer) 3
 127.0.0.1:6379>

Remove elements

127.0.0.1:6379> lpush list one
 (integer) 1
 127.0.0.1:6379> lpush list two
 (integer) 2
 127.0.0.1:6379> lpush list three
 (integer) 3
 127.0.0.1:6379> llen list
 (integer) 3
 127.0.0.1:6379> lpush list three
 (integer) 4
 127.0.0.1:6379> lrange list 0 -1
 1) "three"
 2) "three"
 3) "two"
 4) "one"
 127.0.0.1:6379> lrem list 1 one # Remove the value specified by the list
 (integer) 1
 127.0.0.1:6379> lrange list 0 -1
 1) "three"
 2) "three"
 3) "two"
 127.0.0.1:6379> lrem list 2 three # Remove the value specified in the list
 (integer) 2
 127.0.0.1:6379> lrange list 0 -1
 1) "two"
 127.0.0.1:6379>

Only a part of the value of the trim operation is retained

127.0.0.1:6379> rpush mylist "hello"
 (integer) 1
 127.0.0.1:6379> rpush mylist "hello1"
 (integer) 2
 127.0.0.1:6379> rpush mylist "hello2"
 (integer) 3
 127.0.0.1:6379> rpush mylist "hello3"
 (integer) 4
 127.0.0.1:6379> ltrim mylist 1 2 # Intercept the specified length by subscript, the value of list changes
 OK
 127.0.0.1:6379> lrange mylist 0 -1
 1) "hello1"
 2) "hello2"
 127.0.0.1:6379>

rpoplpush

Remove the last element of the list and move it to the new list

127.0.0.1:6379> rpush mylist "hello"
(integer) 1
127.0.0.1:6379> rpush mylist "hello1"
(integer) 2
127.0.0.1:6379> rpush mylist "hello2"
(integer) 3
127.0.0.1:6379> rpoplpush mylist myotherlist
"hello2"
127.0.0.1:6379> lrange mylist 0 -1
1) "hello"
2) "hello1"
127.0.0.1:6379> lrange myotherlist 0 -1
1) "hello2"
127.0.0.1:6379>

lset

Replace the value specified in the list with another value, update the operation

127.0.0.1:6379> exists list # determine whether this list exists
 (integer) 0
 127.0.0.1:6379> lset list 0 item # If the list does not exist, an error will be reported during update
 (error) ERR no such key
 127.0.0.1:6379>
 127.0.0.1:6379> lpush list value1
 (integer) 1
 127.0.0.1:6379> lrange list 0 0
 1) "value1"
 127.0.0.1:6379> lset list 0 item # If it exists, the value of the specified subscript will be updated
 OK
 127.0.0.1:6379> lrange list 0 0
 1) "item"
 127.0.0.1:6379>
 127.0.0.1:6379> lset list 1 other # If it does not exist, an error will be reported
 (error) ERR index out of range
 127.0.0.1:6379>

linsert

Insert a specific value into the front or back of an element in the list

127.0.0.1:6379> rpush mylist "hello"
(integer) 1
127.0.0.1:6379> rpush mylist "world"
(integer) 2
127.0.0.1:6379> linsert mylist before world my
(integer) 3
127.0.0.1:6379> lrange mylist 0 -1
1) "hello"
2) "my"
3) "world"
127.0.0.1:6379> linsert mylist after my only
(integer) 4
127.0.0.1:6379> lrange mylist 0 -1
1) "hello"
2) "my"
3) "only"
4) "world"
127.0.0.1:6379>

 

  • It is actually a linked list, before Node after, you can insert values ​​in left and right
  • If the key does not exist, create a new link
  • If the key exists, add new elements
  • If all values ​​are removed, the empty link table
  • Insert or update values ​​on both sides, the most efficient! Intermediate elements will be relatively low in efficiency.

Applicable scenarios

  • Message Queue
  • Stack

 

 

003 || Set

 

127.0.0.1:6379> sadd myset hello # Add elements to set
 (integer) 1
 127.0.0.1:6379> sadd myset harley
 (integer) 1
 127.0.0.1:6379> smembers myset # View the value in set
 1) "harley"
 2) "hello"
 127.0.0.1:6379> sadd myset loveyl
 (integer) 1
 127.0.0.1:6379> smembers myset
 1) "harley"
 2) "loveyl"
 3) "hello"
 127.0.0.1:6379> sadd myset hello # The value in the set is unordered and not repeated
 (integer) 0
 127.0.0.1:6379>
 127.0.0.1:6379> sismember myset harley # Check whether there is a value in the set
 (integer) 1
 127.0.0.1:6379> sismember myset hello
 (integer) 1

scard

Get the number of content elements in the set collection

127.0.0.1:6379> smembers myset
1) "harley"
2) "loveyl"
3) "hello"
127.0.0.1:6379> scard myset
(integer) 3

srem

Remove the specified value in set

127.0.0.1:6379> srem myset hello
(integer) 1
127.0.0.1:6379> smembers myset
1) "harley"
2) "loveyl"
127.0.0.1:6379> scard myset
(integer) 2
127.0.0.1:6379>

srandmemeber

Randomly select an element

127.0.0.1:6379> smembers myset
1) "hahaha"
2) "harley"
3) "world"
4) "loveyl"
5) "hello"
127.0.0.1:6379> srandmember myset
"harley"
127.0.0.1:6379> srandmember myset
"world"
127.0.0.1:6379> srandmember myset
"hello"
127.0.0.1:6379> srandmember myset
"loveyl"
127.0.0.1:6379> 
127.0.0.1:6379> srandmember myset 2
1) "loveyl"
2) "world"
127.0.0.1:6379>

spop

Randomly delete an element

127.0.0.1:6379> spop myset
"hello"
127.0.0.1:6379> spop myset
"hahaha"
127.0.0.1:6379> smembers myset
1) "loveyl"
2) "harley"
3) "world"
127.0.0.1:6379>

smove

Move a specified value to another set

127.0.0.1:6379> sadd myset hello
(integer) 1
127.0.0.1:6379> sadd myset world
(integer) 1
127.0.0.1:6379> sadd myset harley
(integer) 1
127.0.0.1:6379> smove myset myset2 harley
(integer) 1
127.0.0.1:6379> smembers myset2
1) "harley"
127.0.0.1:6379> smembers myset
1) "world"
2) "hello"
127.0.0.1:6379>

Difference & Intersection & Convergence

127.0.0.1:6379> sadd key1 a
 (integer) 1
 127.0.0.1:6379> sadd key1 b
 (integer) 1
 127.0.0.1:6379> sadd key1 c
 (integer) 1
 127.0.0.1:6379> sadd key2 c
 (integer) 1
 127.0.0.1:6379> sadd key2 d
 (integer) 1
 127.0.0.1:6379> sadd key2 e
 (integer) 1
 127.0.0.1:6379> sdiff key1 key2 # Difference set
 1) "a"
 2) "b"
 127.0.0.1:6379> sinter key1 key2 # Intersection
 1) "c"
 127.0.0.1:6379>
 127.0.0.1:6379> sunion key1 key2 # union
 1) "a"
 2) "b"
 3) "c"
 4) "e"
 5) "d"
 127.0.0.1:6379>

 

004 || Hash

127.0.0.1:6379> hset myhash field1 harley # set a specific key-value
 (integer) 1
 127.0.0.1:6379> hget myhash field1
 "harley"
 127.0.0.1:6379> hmset myhash field1 hello field2 world # set multiple key-values
 OK
 127.0.0.1:6379> hmget myhash field1 field2 # Get multiple field values
 1) "hello"
 2) "world"
 127.0.0.1:6379> hgetall myhash # Get all data
 1) "field1"
 2) "hello"
 3) "field2"
 4) "world"
 127.0.0.1:6379> hdel myhash field1 # Delete the specified key, the value will also be deleted
 (integer) 1
 127.0.0.1:6379> hgetall myhash
 1) "field2"
 2) "world"
 127.0.0.1:6379>
 127.0.0.1:6379> hlen myhash # Check the number of fields of hash
 (integer) 1
 127.0.0.1:6379>
 127.0.0.1:6379> hexists myhash field1 # determine whether the specified field in hash exists
 (integer) 0
 127.0.0.1:6379> hexists myhash field2
 (integer) 1
 127.0.0.1:6379>
 127.0.0.1:6379> hkeys myhash # Get all fields
 1) "field2"
 127.0.0.1:6379> hvals myhash # Get all values
 1) "world"

hincrby & hsetnx

127.0.0.1:6379> hset myhash field3 5
 (integer) 1
 127.0.0.1:6379> hincrby myhash field3 1 # Specify increment
 (integer) 6
 127.0.0.1:6379> hgetall myhash
 1) "field3"
 2) "6"
 127.0.0.1:6379> hincrby myhash field3 -2
 (integer) 4
 127.0.0.1:6379> hgetall myhash
 1) "field3"
 twenty four"
 127.0.0.1:6379> hsetnx myhash field4 hello # If it does not exist, you can set the value
 (integer) 1
 127.0.0.1:6379> hsetnx myhash field4 world # If it exists, the execution will fail
 (integer) 0
 127.0.0.1:6379>

hash changed data user

127.0.0.1:6379> hset user:1 name harley
(integer) 1
127.0.0.1:6379> hget user:1 name
"harley"
127.0.0.1:6379>

Applicable scenarios

  • It can be used to store user information and frequently changing information.
  • Hash is more suitable for object storage, and String is more suitable for string storage.

 

 

005 || Zset

Ordered set, adding a value to set

127.0.0.1:6379> zadd myzset 1 one
 (integer) 1
 127.0.0.1:6379> zadd myzset 2 two
 (integer) 1
 127.0.0.1:6379> zadd myzset 3 three 4 four # Add multiple values
 (integer) 2
 127.0.0.1:6379> zrange myzset 0 -1
 1) "one"
 2) "two"
 3) "three"
 4) "four"
 127.0.0.1:6379>

zrangebyscore

Sort

127.0.0.1:6379> zadd salary 2500 harley
 (integer) 1
 127.0.0.1:6379> zadd salary 5000 cc_zeal
 (integer) 1
 127.0.0.1:6379> zadd salary 500 jone
 (integer) 1
 127.0.0.1:6379> zrangebyscore salary -inf +inf # Sort in ascending order of score
 1) "jone"
 2) "harley"
 3) "cc_zeal"
 127.0.0.1:6379>
 127.0.0.1:6379> zrevrange salary 0 -1 # descending order
 1) "cc_zeal"
 2) "harley"
 3) "jone"
 127.0.0.1:6379>
 127.0.0.1:6379> zrangebyscore salary -inf +inf withcores
 1) "jone"
 2) "500"
 3) "harley"
 4) "2500"
 5) "cc_zeal"
 6) "5000"
 127.0.0.1:6379>
 127.0.0.1:6379> zrangebyscore salary -inf 2500 withscores # Show ascending order less than 2500
 1) "jone"
 2) "500"
 3) "harley"
 4) "2500"
 127.0.0.1:6379>

zrem

127.0.0.1:6379> zrange salary 0 -1
 1) "jone"
 2) "harley"
 3) "cc_zeal"
 127.0.0.1:6379> zrem salary jone # Remove the specified element in the ordered collection
 (integer) 1
 127.0.0.1:6379> zrange salary 0 -1
 1) "harley"
 2) "cc_zeal"
 127.0.0.1:6379>
 127.0.0.1:6379> zcard salary # Get the number of ordered sets
 (integer) 2
 127.0.0.1:6379>
 127.0.0.1:6379> zadd myset 1 hello
 (integer) 1
 127.0.0.1:6379> zadd myset 2 world 3 harley
 (integer) 2
 127.0.0.1:6379> zcount myset 1 3 # Get the number of members of the specified interval
 (integer) 3
 127.0.0.1:6379> zcount myset 1 2
 (integer) 2
 127.0.0.1:6379>

 

006 || Geospatial

Geographic location, calculating the information of geographical location, and the distance between the two places.

geoadd

Adding geographical locations, the poles cannot be added directly, and city data will be downloaded and imported at one time using Java programs.

key value (dimension, precision, name)

127.0.0.1:6379> geoadd china:city 116.40 39.90 beijing # Add the coordinates of the city
 (integer) 1
 127.0.0.1:6379> geoadd china:city 121.47 31.23 shanghai
 (integer) 1
 127.0.0.1:6379> geoadd china:city 106.50 29.53 chongqing
 (integer) 1
 127.0.0.1:6379> geoadd china:city 114.05 22.52 shenzhen
 (integer) 1
 127.0.0.1:6379> geoadd china:city 120.16 30.24 hangzhou 108.96 34.26 xian
 (integer) 2

geops

127.0.0.1:6379> geopos china:city beijing # Get the latitude and latitude of the specified city
 1) 1) "116.39999896287918091"
    2) "39.90000009167092543"
 127.0.0.1:6379> geopos china:city beijing shanghai
 1) 1) "116.39999896287918091"
    2) "39.90000009167092543"
 2) 1) "121.47000163793563843"
    2) "31.22999903975783553"
 127.0.0.1:6379>

geodist

127.0.0.1:6379> geodist china:city beijing shanghai # Get the straight line distance between two places
 "1067378.7564"
 127.0.0.1:6379>
 127.0.0.1:6379> geodist China:city beijing shanghai km # Get the straight line distance between the two places (unit km)
 "1067.3788"
 127.0.0.1:6379>

georadius

Find elements within a certain radius with a given latitude and longitude as the center

127.0.0.1:6379> georadius china:city 110 30 1000 km
 1) "chongqing"
 2) "xian"
 3) "shenzhen"
 4) "hangzhou"
 127.0.0.1:6379> georadius china:city 110 30 500 km
 1) "chongqing"
 2) "xian"
 127.0.0.1:6379>
 127.0.0.1:6379> georadius china:city 110 30 500 km withcoord # Latitude and Longitude
 1) 1) "chongqing"
    2) 1) "106.49999767541885376"
       2) "29.52999957900659211"
 2) 1) "xian"
    2) 1) "108.96000176668167114"
       2) "34.25999964418929977"
 127.0.0.1:6379> georadius china:city 110 30 500 km withdist # straight line distance
 1) 1) "chongqing"
    2) "341.9374"
 2) 1) "xian"
    2) "483.8340"

georadiusbymember

Find other elements around the specified element

127.0.0.1:6379> georadiusbymember china:city shanghai 500 km
1) "hangzhou"
2) "shanghai"
127.0.0.1:6379>

geohash

Convert two-dimensional latitude and longitude into one-dimensional strings. If the two strings are closer, the closer they are.

127.0.0.1:6379> geohash china:city beijing chongqing
 1) "wx4fbxxfke0" # Latitude and longitude hash
 2) "wm5xzrybty0" # Latitude and longitude hash
 127.0.0.1:6379>

Clear

The underlying geo is zset, and you can use the zset command to clear the elements of geo

127.0.0.1:6379> zrange china:city 0 -1
1) "chongqing"
2) "xian"
3) "shenzhen"
4) "hangzhou"
5) "shanghai"
6) "beijing"
127.0.0.1:6379> zrem china:city xian
(integer) 1
127.0.0.1:6379> zrange china:city 0 -1
1) "chongqing"
2) "shenzhen"
3) "hangzhou"
4) "shanghai"
5) "beijing"
127.0.0.1:6379>

 

007 || Hyperloglog

 

 

008 || bitmap

 

 

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