Redis五大基本数据类型之Set类型

一、Set类型数据的基本操作

1.1 Set类型数据基本性质

1. Set类型数据中不存在重复值

2. Set中的数据是无序的

   1.2 常用命令之增删改查

3. sadd key member1 ... membern：向集合key中添加元素memberi

   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 xiaohe
   (integer) 1

4. smembers key：查询集合key中的元素

   127.0.0.1:6379> smembers myset
   1) "xiaohe"
   2) "world"
   3) "hello"

5. sismember key member：查询集合key中是否存在元素member

   127.0.0.1:6379> smembers myset
   1) "xiaohe"
   2) "world"
   3) "hello"
   127.0.0.1:6379> sismember myset xiaohe
   (integer) 1
   127.0.0.1:6379> sismember myset test
   (integer) 0

6. scard key:获取集合key中的元素个数

   127.0.0.1:6379> scard myset
   (integer) 3

7. srem key member1 ... membern:移除集合key中的指定元素memberi

   127.0.0.1:6379> smembers myset
   1) "xiaohe"
   2) "world"
   3) "hello"
   127.0.0.1:6379> srem myset hello
   (integer) 1
   127.0.0.1:6379> smembers myset
   1) "xiaohe"
   2) "world"

8. srandmember key [count]:从集合key中随机选出count个元素

   127.0.0.1:6379> smembers myset
   1) "xiaohe"
   2) "world"
   127.0.0.1:6379> SRANDMEMBER myset 1
   1) "world"
   127.0.0.1:6379> SRANDMEMBER myset 1
   1) "world"
   127.0.0.1:6379> SRANDMEMBER myset
   "world"
   127.0.0.1:6379> SRANDMEMBER myset
   "world"
   127.0.0.1:6379> SRANDMEMBER myset
   "xiaohe"
   127.0.0.1:6379> SRANDMEMBER myset 2
   1) "world"
   2) "xiaohe"

9. spop key [count]:从集合key中随机删除count个元素

   127.0.0.1:6379> SMEMBERS myset
   1) "0"
   2) "1"
   3) "2"
   4) "3"
   5) "4"
   127.0.0.1:6379> spop myset
   "0"
   127.0.0.1:6379> spop myset 1
   1) "3"

10. smove source destination member：将集合source中的元素member移动到集合destination中

    127.0.0.1:6379> sadd myset 0 1 2 3
    (integer) 4
    127.0.0.1:6379> sadd myset2 4 5 6
    (integer) 3
    127.0.0.1:6379> smove myset myset2 0
    (integer) 1
    127.0.0.1:6379> SMEMBERS myset
    1) "1"
    2) "2"
    3) "3"
    127.0.0.1:6379> SMEMBERS myset2
    1) "0"
    2) "4"
    3) "5"
    4) "6"

    1.3 进阶命令

11. sdiff key1 key2：查询集合key1与集合key2不同的元素

    127.0.0.1:6379> sadd set1 0 1 2 3
    (integer) 4
    127.0.0.1:6379> sadd set2 2 3 4 5
    (integer) 4
    127.0.0.1:6379> sdiff set1 set2
    1) "0"
    2) "1"

12. sinter key1 key2：查询集合key1与集合key2交集

    1. 可用于实现共同好友、共同关注、二度好友、推荐好友等操作

       127.0.0.1:6379> sadd set1 0 1 2 3
       (integer) 4
       127.0.0.1:6379> sadd set2 2 3 4 5
       (integer) 4
       127.0.0.1:6379> sinter set1 set2
       1) "2"
       2) "3"

13. sunion key1 ... keyn：求集合key1 ... keyn的并集

    127.0.0.1:6379> sunion set1 set2
    1) "0"
    2) "1"
    3) "2"
    4) "3"
    5) "4"
    6) "5"
    127.0.0.1:6379> sunion set1 set2 set3
    1) "0"
    2) "1"
    3) "2"
    4) "3"
    5) "4"
    6) "5"
    7) "6"