Redis04_五大基本数据类型

亦凉 2022-12-01 15:59 220阅读 0赞

### 五大基本数据类型 ###

*   *   *  String类型
         *  List类型
         *  Set 类型
         *  Hash（哈希）类型
         *  Zset 有序集合类型

--------------------

### String类型 ###

**append 给指定key追加值，如果当前key不存在，就相当于set key**  
**strlen 获取字符串的长度**

127.0.0.1:6379> append name hello
    (integer) 8
    127.0.0.1:6379> get name
    "BLUhello"
    127.0.0.1:6379> strlen name
    (integer) 8

**incr 将key中存储的数字值加1 i++**  
**decr 将key中存储的数字值减1 i- -**  
**incrby 将key中存储的数字值增加指定值 i+=10**  
**decrby 将key中存储的数字值减少指定值 i-=7**

127.0.0.1:6379> set views 0
    OK
    127.0.0.1:6379> get views
    "0"
    127.0.0.1:6379> incr views
    (integer) 1
    127.0.0.1:6379> get views
    "1"
    127.0.0.1:6379> decr views
    (integer) 0
    127.0.0.1:6379> get views
    "0"
    127.0.0.1:6379> incrby views 10
    (integer) 10
    127.0.0.1:6379> get views
    "10"
    127.0.0.1:6379> decrby views 7
    (integer) 3
    127.0.0.1:6379> get views
    "3"

**getrange 截取字符串（闭区间），0到-1表示获取全部字符串**  
**setrange 替换字符串**

127.0.0.1:6379> set key1 hello,BLU!
    OK
    127.0.0.1:6379> getrange key1 0 3
    "hell"
    127.0.0.1:6379> getrange key1 0 -1
    "hello,BLU!"
    127.0.0.1:6379> setrange key1 2 xx
    (integer) 10
    127.0.0.1:6379> get key1
    "hexxo,BLU!"

**setex 设置key同时设置过期时间：set with expire**  
**setnx 创建key(如果不存在)：set if not exist**

127.0.0.1:6379> setex key2 30 Hello!!
    OK
    127.0.0.1:6379> ttl key2
    (integer) 22
    
    127.0.0.1:6379> setnx key3 BLUBLU
    (integer) 1
    127.0.0.1:6379> setnx key3 BLUBLUBLU
    (integer) 0
    127.0.0.1:6379> get key3
    "BLUBLU"

**mset 批量创建key**  
**mget 批量获取key**  
**msetnx 批量创建key(如果不存在) (属于原子性操作，只要有一个存在，都会创建失败)**

127.0.0.1:6379> mset key1 v1 key2 v2 key3 v3
    OK
    127.0.0.1:6379> keys *
    1) "key3"
    2) "key2"
    3) "key1"
    127.0.0.1:6379> mget key1 key2 key3
    1) "v1"
    2) "v2"
    3) "v3"
    127.0.0.1:6379> msetnx key1 v1 key2 v2 key3 v3 key4 v4
    (integer) 0
    127.0.0.1:6379> mget key1 key2 key3 key4
    1) "v1"
    2) "v2"
    3) "v3"
    4) (nil)

**保存对象的两种方式**

set user:1 { name:zhangsan,age:3}
    OK
    127.0.0.1:6379> get user:1
    "{name:zhangsan,age:3}"
    
    
    127.0.0.1:6379> mset user:1:name zhangsan user:1:age 18
    OK
    127.0.0.1:6379> mget user:1:name user:1:age
    1) "zhangsan"
    2) "18"

**getset 获取key的同时创建/修改值**

127.0.0.1:6379> getset db redis
    (nil)
    127.0.0.1:6379> get db
    "redis"
    127.0.0.1:6379> getset db mysql
    "redis"
    127.0.0.1:6379> get db
    "mysql"

--------------------

### List类型 ###

**本质上是一个链表，在两边插入或改动值效率较高，更新中间元素效率偏低**

**左存右取** 相当于 **队列**  
**左存左取** 相当于 **栈**

**lpush 将值插入 list 头部**  
**rpush 将值插入 list 尾部**  
**lrange 获取 list 中具体区间的值 0到-1表示获取所有**

127.0.0.1:6379> lpush list1 one
    (integer) 1
    127.0.0.1:6379> lpush list1 two
    (integer) 2
    127.0.0.1:6379> lpush list1 three
    (integer) 3
    127.0.0.1:6379> rpush list1 right
    (integer) 4
    127.0.0.1:6379> lrange list1 0 -1
    1) "three"
    2) "two"
    3) "one"
    4) "right"
    127.0.0.1:6379> lrange list1 0 1
    1) "three"
    2) "two"

**lpop 移除 list 头部的值**  
**rpush 移除 list 尾部的值**

**lindex 通过下标获取 list 中的值（从0开始）**  
**llen 获取 list 的长度**

127.0.0.1:6379> lpop list1
    "three"
    127.0.0.1:6379> lrange list1 0 -1
    1) "two"
    2) "one"
    3) "right"
    127.0.0.1:6379> rpop list1
    "right"
    127.0.0.1:6379> lrange list1 0 -1
    1) "two"
    2) "one"
    127.0.0.1:6379> lindex list1 0
    "two"
    127.0.0.1:6379> llen list1
    (integer) 2

**list 中可以存在重复的值**  
**lrem 移除指定个数的指定值**  
**ltrim 通过下标截断 list**   
**rpoplpush 移除指定 list 尾部的值，并存入新的 list 的头部**

127.0.0.1:6379> lpush list1 three
    (integer) 3
    127.0.0.1:6379> lpush list1 three
    (integer) 4
    127.0.0.1:6379> lpush list1 three
    (integer) 5
    127.0.0.1:6379> lrange list1 0 -1
    1) "three"
    2) "three"
    3) "three"
    4) "two"
    5) "one"
    127.0.0.1:6379> lrem list1 2 three
    (integer) 2
    127.0.0.1:6379> lrange list1 0 -1
    1) "three"
    2) "two"
    3) "one"
    127.0.0.1:6379> ltrim list1 0 1
    OK
    127.0.0.1:6379> lrange list1 0 -1
    1) "three"
    2) "two"
    127.0.0.1:6379> rpoplpush list1 list2
    "two"
    127.0.0.1:6379> lrange list1 0 -1
    1) "three"
    127.0.0.1:6379> lrange list2 0 -1
    1) "two"

**exists 判断指定 list 是否存在**  
**lset 修改 list 中指定下标的值（若 list 不存在或指定下标不存在将报错）**

127.0.0.1:6379> exists list1
    (integer) 0
    127.0.0.1:6379> lset list1 0 item
    (error) ERR no such key
    127.0.0.1:6379> lpush list1 v1
    (integer) 1
    127.0.0.1:6379> lrange list1 0 -1
    1) "v1"
    127.0.0.1:6379> lset list1 0 item1
    OK
    127.0.0.1:6379> lset list1 1 item2
    (error) ERR index out of range

**linsert 在 list 中指定值的前后(before after)插入值**

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

--------------------

### Set 类型 ###

**set 中的元素无序且不能重复**  
**sadd 往set里添加值**  
**smembers 获取set里的值**  
**sismember 判断指定值在set里是否存在，存在返回1，不存在返回0**  
**scard 获取set中元素的数量**  
**srem 移除set中指定的元素**  
**srandmember 从set中随机取出指定个数的元素**  
**spop 从set中随机移除一个元素**  
**smove 将set中的指定元素移出至另一个set**

127.0.0.1:6379> sadd myset hello
    (integer) 1
    127.0.0.1:6379> sadd myset BLU
    (integer) 1
    127.0.0.1:6379> sadd myset happy
    (integer) 1
    127.0.0.1:6379> sadd myset everyday
    (integer) 1
    127.0.0.1:6379> smembers myset
    1) "happy"
    2) "BLU"
    3) "everyday"
    4) "hello"
    127.0.0.1:6379> sismember myset BLU
    (integer) 1
    127.0.0.1:6379> scard myset
    (integer) 4
    127.0.0.1:6379> srem myset hello
    (integer) 1
    127.0.0.1:6379> srandmember myset
    "happy"
    127.0.0.1:6379> srandmember myset 2
    1) "happy"
    2) "everyday"
    127.0.0.1:6379> spop myset
    "everyday"
    127.0.0.1:6379> smembers myset
    1) "happy"
    2) "BLU"
    127.0.0.1:6379> smove myset myset2 BLU
    (integer) 1
    127.0.0.1:6379> smembers myset
    1) "happy"
    127.0.0.1:6379> smembers myset2
    1) "BLU"

**sdiff 比较a集合与b集合，返回a集合独有的元素（差集）**  
**sinter 比较a集合与b集合，返回两集合共有的元素（交集）**  
**例子：查询两个用户的共同关注、共同好友**

**sunion 比较a集合与b集合，返回两集合所有的元素（并集）**

sadd set1 a
    sadd set1 b
    sadd set1 c
    sadd set1 d
    sadd set2 c
    sadd set2 d
    sadd set2 e
    127.0.0.1:6379> sdiff set1 set2
    1) "a"
    2) "b"
    127.0.0.1:6379> sinter set1 set2
    1) "c"
    2) "d"
    127.0.0.1:6379> sunion set1 set2
    1) "e"
    2) "c"
    3) "d"
    4) "b"
    5) "a"

--------------------

### Hash（哈希）类型 ###

**hset 存值**  
**hget 取值**  
**hmset 批量存值**  
**hmget 批量取值**  
**hgetall 取出hash中的所有key和value**  
**hdel 删除指定字段**  
**hlen 获取哈希的长度（字段数量）**  
**hexists 判断指定字段是否存在**  
**hkeys 获取所有的key**  
**hvals 获取所有的值**

127.0.0.1:6379> hset myhash field1 BLU
    (integer) 1
    127.0.0.1:6379> hget myhash field1
    "BLU"
    127.0.0.1:6379> hmset myhash field2 hello field3 world
    OK
    127.0.0.1:6379> hmget myhash field1 field2 field3
    1) "BLU"
    2) "hello"
    3) "world"
    127.0.0.1:6379> hgetall myhash
    1) "field1"
    2) "BLU"
    3) "field2"
    4) "hello"
    5) "field3"
    6) "world"
    127.0.0.1:6379> hdel myhash field3
    (integer) 1
    127.0.0.1:6379> hlen myhash
    (integer) 2
    127.0.0.1:6379> hexists myhash field1
    (integer) 1
    127.0.0.1:6379> hkeys myhash
    1) "field1"
    2) "field2"
    127.0.0.1:6379> hvals myhash
    1) "BLU"
    2) "hello"

**hincrby 将指定字段的数字值增加指定大小**  
 **hsetnx 存值（如果key不存在），如果key已存在，则存值失败**

127.0.0.1:6379> hset myhash field3 7
    (integer) 1
    127.0.0.1:6379> hincrby myhash field3 3
    (integer) 10
    127.0.0.1:6379> hsetnx myhash field4 hahaha
    (integer) 1
    127.0.0.1:6379> hsetnx myhash field4 lollollol
    (integer) 0

**Hash 比 String 更适合存储对象**

127.0.0.1:6379> hset user:1 name zhangsan
    (integer) 1
    127.0.0.1:6379> hset user:1 age 26
    (integer) 1
    127.0.0.1:6379> hget user:1 name
    "zhangsan"
    127.0.0.1:6379> hget user:1 age
    "26"

--------------------

### Zset 有序集合类型 ###

**应用：排行榜**

**zadd 往Zset里添加值**  
**zrange 获取Zset中具体区间的值（默认根据score由低到高排序）**

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

**zrangebyscore 根据score排序，-inf 表示负无穷 +inf 表示正无穷，withscores表示显示score值，**   
**zrevrange 倒序排序**

127.0.0.1:6379> zadd salary 2500 zhangsan 5000 lisi 1200 BLU
    (integer) 3
    127.0.0.1:6379> zrangebyscore salary -inf +inf
    1) "BLU"
    2) "zhangsan"
    3) "lisi"
    127.0.0.1:6379> zrangebyscore salary -inf +inf withscores
    1) "BLU"
    2) "1200"
    3) "zhangsan"
    4) "2500"
    5) "lisi"
    6) "5000"
    127.0.0.1:6379> zrangebyscore salary -inf 2500 withscores
    1) "BLU"
    2) "1200"
    3) "zhangsan"
    4) "2500"
    127.0.0.1:6379> zrevrange salary 0 -1 withscores
    1) "lisi"
    2) "5000"
    3) "zhangsan"
    4) "2500"
    5) "BLU"
    6) "1200"

**zrem 移除Zset里的指定值**  
**zcard 统计Zset里值的数量**  
**zcount 统计指定区间里值的数量**

127.0.0.1:6379> zrem salary lisi
    (integer) 1
    127.0.0.1:6379> zcard salary
    (integer) 2
    
    127.0.0.1:6379> zadd myset 1 hello 2 world 3 BLU
    (integer) 3
    127.0.0.1:6379> zcount myset 1 3
    (integer) 3
    127.0.0.1:6379> zcount myset 2 3
    (integer) 2