【Redis】Redis学习——五大基本数据类型

前言

Redis：REmote DIctionary Server（远程字典服务器）是完全开源免费的,用C语言编写的,遵守BSD协议,是一个高性能（Key/Value）分布式内存数据库,基于内存运行,并支持持久化的NoSQL数据库,是当前最热门的NoSQL数据库之一.它通常被称为数据结构服务器,因为值（value）可以是 字符串(String), 哈希(Map), 列表(list), 集合(sets) 和 有序集合(sorted sets)等类型.

一、字符串(String)

特点：一个key对应一个value,value可以是string也可以为数字

string是 Redis最基本的类型,一个key对应一个value.Redis string 类型是二进制安全的.即Redis的string可以包含任何数据,比如jpg图片或者序列化的对象 .Redis stringType a key can store the maximum512MB 数据.

127.0.0.1:6379> set name chandler #设定键name值
OK
127.0.0.1:6379> get name  #获得键name的值
"chandler"
127.0.0.1:6379> getrange name 0 -1 #获取nameValue substring,0代表字符串开头,-1Represents the end of the string
"chandler"
127.0.0.1:6379> getrange name 0 3 #获取索引0-3的子字符串
"chan"
127.0.0.1:6379> getset name monica #先get后set
"chandler"
127.0.0.1:6379> get name
"monica"
127.0.0.1:6379> mset friend1 ross friend2 rachel #Set multiple key-values ​​at the same time
OK
127.0.0.1:6379> mget friend1 friend2 #同时获取多个键值
1) "ross"
2) "rachel"
127.0.0.1:6379> set word "hello"
OK
127.0.0.1:6379> append word " world" #Append a string to the string value
(integer) 11
127.0.0.1:6379> get word
"hello world"
127.0.0.1:6379> strlen word #获取键word的值的长度
(integer) 11
127.0.0.1:6379> setrange word 6 linux #从索引为6used after the element“linux”进行覆盖
(integer) 11
127.0.0.1:6379> get word
"hello linux"
127.0.0.1:6379> set age 30
OK
127.0.0.1:6379> incr age #让数值增加1
(integer) 31
127.0.0.1:6379> incrby age 5 #数值增加5
(integer) 36
127.0.0.1:6379> decrby age 10 #数值减少10
(integer) 26
127.0.0.1:6379> decr age #数值减少1
(integer) 25
127.0.0.1:6379> setex friend3 30 joey #设置键friends3的生存时间为30s,值为joey
OK
127.0.0.1:6379> ttl friend3
(integer) 26
127.0.0.1:6379> setnx age 30 #age存在,No value will be set
(integer) 0
127.0.0.1:6379> get age
"25"
127.0.0.1:6379> setnx age2 30 #age2不存在,Set the value toage2
(integer) 1
127.0.0.1:6379> get age2
"30"

二、列表(List)

特点：一个key对应多个value

Redis的List是简单的字符串列表,按照插入顺序排序.Redis的list是每个子元素都是String类型的双向链表,可以通过push和pop操作从列表的头部或者尾部添加或者删除元素,这样List即可以作为栈,也可以作为队列.ListOne application is message queues,可以利用List的PUSH操作,将任务存在List中,然后工作线程再用POP操作将任务取出进行执行.Redis还提供了操作List中某一段的api,你可以直接查询,删除List中某一段的元素.

127.0.0.1:6379> lpush friends chandler #在列表friends头部插入chandler
(integer) 1
127.0.0.1:6379> lpush friends monica joey #在列表friendsThe heads are inserted one after the other at the same timemonica joey
(integer) 3
127.0.0.1:6379> lrange friends 0 -1 #查看索引为0的元素到最后一个元素
1) "joey"
2) "monica"
3) "chandler"
127.0.0.1:6379> rpush friends phoebe #在列表friends尾部插入phoebe
(integer) 4
127.0.0.1:6379> lrange friends 0 -1
1) "joey"
2) "monica"
3) "chandler"
4) "phoebe"
127.0.0.1:6379> rpush friends ross rachel #在列表friends尾部依次插入ross rachel
(integer) 6
127.0.0.1:6379> lrange friends 0 -1
1) "joey"
2) "monica"
3) "chandler"
4) "phoebe"
5) "ross"
6) "rachel"
127.0.0.1:6379> linsert friends before joey alan #在列表friends中joey元素之前插入alan
(integer) 7
127.0.0.1:6379> lrange friends 0 -1
1) "alan"
2) "joey"
3) "monica"
4) "chandler"
5) "phoebe"
6) "ross"
7) "rachel"
127.0.0.1:6379> linsert friends after joey bob #在列表friends中joey元素之后插入bob
(integer) 8
127.0.0.1:6379> lrange friends 0 -1
1) "alan"
2) "joey"
3) "bob"
4) "monica"
5) "chandler"
6) "phoebe"
7) "ross"
8) "rachel"
127.0.0.1:6379> lset friends 2 cindy #将列表索引为2的元素值改为cindy
OK
127.0.0.1:6379> lrange friends 0 -1
1) "alan"
2) "joey"
3) "cindy"
4) "monica"
5) "chandler"
6) "phoebe"
7) "ross"
8) "rachel"
127.0.0.1:6379> lpop friends  #Pops an element at the head of the list
"alan"
127.0.0.1:6379> lrange friends 0 -1
1) "joey"
2) "cindy"
3) "monica"
4) "chandler"
5) "phoebe"
6) "ross"
7) "rachel"
127.0.0.1:6379> lpop friends 3 #The header of the list pops up3个元素
1) "joey"
2) "cindy"
3) "monica"
127.0.0.1:6379> lrange friends 0 -1
1) "chandler"
2) "phoebe"
3) "ross"
4) "rachel"
127.0.0.1:6379> rpop friends 2 #The end of the list pops up2个元素
1) "rachel"
2) "ross"
127.0.0.1:6379> lrange friends 0 -1
1) "chandler"
2) "phoebe"
127.0.0.1:6379> llen friends  #查看列表friends的长度
(integer) 2
127.0.0.1:6379> lindex friends 1 #查看索引为1的成员
"phoebe"
127.0.0.1:6379> rpush friends alan bob cindy bob nancy bob
(integer) 8
127.0.0.1:6379> lrem friends 2 bob #移除列表中2和bob元素
(integer) 2
127.0.0.1:6379> lrange friends 0 -1
1) "chandler"
2) "phoebe"
3) "alan"
4) "cindy"
5) "nancy"
6) "bob"
127.0.0.1:6379> ltrim friends 3 5 #保留列表索引3-5元素,rest truncation
OK
127.0.0.1:6379> lrange friends 0 -1
1) "cindy"
2) "nancy"
3) "bob"

三、哈希（Hash）

特点：一个key对应一个value,此valueContains one or more key-value pairs（filed-value）

Redis hash是一个键值对集合.Redis hash是一个string类型的field和value的映射表,hash特别适合用于存储对象.每个hash可以存储 2^32 - 1个键值对

127.0.0.1:6379> hset user name chandler #设置user（key）的name（field）值为chandler
(integer) 1
127.0.0.1:6379> hget user name  #获取user（key）的name（field）值
"chandler"
127.0.0.1:6379> hmset user1 name rachel age 30  #同时设置user1（key）的name、age（field）值
OK
127.0.0.1:6379> hmget user1 name age #同时获取user1（key）的name、age（field）值
1) "rachel"
2) "30"
127.0.0.1:6379> hkeys user #获取user的所有keys
1) "name"
127.0.0.1:6379> hkeys user1 
1) "name"
2) "age"
127.0.0.1:6379> hvals user1 #获取user1所有field值
1) "rachel"
2) "30"
127.0.0.1:6379> hlen user1 #获取user1的字段数量
(integer) 2
127.0.0.1:6379> hincrby user1 age 3 #键user1的age字段值增加3
(integer) 33
127.0.0.1:6379> hdel user1 name age #键user1的name、age字段删除
(integer) 2
127.0.0.1:6379> hkeys user1
(empty array)
127.0.0.1:6379> hexists user1 age #查看user1的age字段是否存在
(integer) 0
127.0.0.1:6379> hexists user name
(integer) 1

四、集合(Set)

特点：一个key对应多个value,成员不重复

Redis的Set是string类型的无序集合.集合是通过哈希表实现的,所以添加,删除,查找的复杂度都是 O(1).集合中最大的成员数为 2^32 - 1.

127.0.0.1:6379> sadd group1 monica chandler phoebe joey #向集合group2中插入monica chandler phoebe joey
(integer) 4
127.0.0.1:6379> sadd group2 phoebe ross rachel joey
(integer) 4
127.0.0.1:6379> scard group1 #查看集合group1中成员个数
(integer) 4
127.0.0.1:6379> sdiff group1 group2 #查看group1相对于group2的差集
1) "monica"
2) "chandler"
127.0.0.1:6379> sdiff group2 group1 #查看group2相对于group1的差集
1) "ross"
2) "rachel"
127.0.0.1:6379> sinter group1 group2 #查看group1与group2的交集
1) "joey"
2) "phoebe"
127.0.0.1:6379> sunion group1 group2 #查看group1与group2的并集
1) "ross"
2) "monica"
3) "phoebe"
4) "rachel"
5) "joey"
6) "chandler"
127.0.0.1:6379> smove group1 group2 monica #将group1（source）中的monica移动到group2（destination）
(integer) 1
127.0.0.1:6379> smembers group1 #查看group1中的所有成员
1) "joey"
2) "phoebe"
3) "chandler"
127.0.0.1:6379> sismember group2 monica #查看group2contains membersmonica
(integer) 1
127.0.0.1:6379> smembers group2
1) "joey"
2) "phoebe"
3) "ross"
4) "monica"
5) "rachel"
127.0.0.1:6379> spop group2 2 #随机从group2removes and returns two elements from 
1) "phoebe"
2) "monica"
127.0.0.1:6379> smembers group2
1) "ross"
2) "rachel"
3) "joey"
127.0.0.1:6379> srandmember group2 2 #随机从group2Returns two elements in （不移除）
1) "ross"
2) "joey"
127.0.0.1:6379> smembers group2
1) "ross"
2) "rachel"
3) "joey"
127.0.0.1:6379> srem group2 ross joey #删除group2中ross joey成员
(integer) 2
127.0.0.1:6379> smembers group2
1) "rachel"
127.0.0.1:6379> 

五、有序集合(Sorted Set)

特点：一个key对应多个value,在setBased on the addition of a for sortingscore

Redis的zset和set一样也是 string 类型元素的集合,且不允许重复的成员.不同的是每个元素都会关联一个double类型的分数.RedisIt is by scores that the members of the set are sorted from smallest to largest.zset 的成员是唯一的,但分数(score)却可以重复.

127.0.0.1:6379> zadd friends 1 chandler 3 monica  5 phoebe  7 joey  8 ross 9 rachel#Add members and corresponding to the sorted set respectivelyscore
(integer) 6
127.0.0.1:6379> zcard friends #查看friends中成员个数
(integer) 6
127.0.0.1:6379> zcount friends -inf +inf #计算scoreThe number of members from negative infinity to positive infinity
(integer) 6
127.0.0.1:6379> zcount friends 3 8
(integer) 4
127.0.0.1:6379> zrange friends 2 6 #返回索引在2-6之间的成员
1) "phoebe"
2) "joey"
3) "ross"
4) "rachel"
127.0.0.1:6379> zrank friends monica #返回friends中成员monica的索引
(integer) 1
127.0.0.1:6379> zrem friends monica chandler #移除成员monica chandler
(integer) 2
127.0.0.1:6379> zscore friends joey #查看成员joey的score
"7"
127.0.0.1:6379> zrange friends 0 10
1) "phoebe"
2) "joey"
3) "ross"
4) "rachel"
127.0.0.1:6379> zrank friends ross
(integer) 2
127.0.0.1:6379> zincrby friends 3 phoebe #对成员phoebe的score增加3
"8"
127.0.0.1:6379> zscore friends phoebe
"8"
127.0.0.1:6379> zrangebyscore friends -inf +inf withscores #Returns a list of members in increasing order
1) "joey"
2) "7"
3) "phoebe"
4) "8"
5) "ross"
6) "8"
7) "rachel"
8) "9"

总结

本文整理了RedisThe use of five basic data structures,分别是字符串String、列表List、哈希Hash、集合Set、有序集合ZSet.Introduces the common commands of five data types and how to use them.

参考资料

redis官方文档