redis set
- 官方命令地址：https://redis.io/commands/?group=set
- 客户端查看命令：
help @set
set
- set 类似go的map，但是value值是struct{}。它具备以下特征：
- 无序、元素不可重复、查找快、支持交集.并集.差集等功能
SADD
-
向set添加一个或多个成员。如果key不存在，则创建该key。
-
语法：
SADD key member [member ...]
- 示例：
redis> SADD myset "Hello"
(integer) 1
redis> SADD myset "World"
(integer) 1
redis> SADD myset "World"
(integer) 0
redis> SMEMBERS myset
1) "Hello"
2) "World"
SCARD
-
返回set中成员的数目。
-
语法：
SCARD key
- 示例：
redis> SADD myset "Hello"
(integer) 1
redis> SADD myset "World"
(integer) 1
redis> SCARD myset
(integer) 2
SDIFF
-
返回多个set的差值。
-
语法：
SDIFF key [key ...]
- 示例：
redis> SADD key1 "a"
(integer) 1
redis> SADD key1 "b"
(integer) 1
redis> SADD key1 "c"
(integer) 1
redis> SADD key2 "c"
(integer) 1
redis> SADD key2 "d"
(integer) 1
redis> SADD key2 "e"
(integer) 1
redis> SDIFF key1 key2
1) "a"
2) "b"
SDIFFSTORE
-
将多个set的差异存储在一个键中。
-
语法：
SDIFFSTORE destination key [key ...]
- 示例：
redis> SADD key1 "a"
(integer) 1
redis> SADD key1 "b"
(integer) 1
redis> SADD key1 "c"
(integer) 1
redis> SADD key2 "c"
(integer) 1
redis> SADD key2 "d"
(integer) 1
redis> SADD key2 "e"
(integer) 1
redis> SDIFFSTORE key key1 key2
(integer) 2
redis> SMEMBERS key
1) "a"
2) "b"
SINTER
-
返回多个set的交点。
-
语法：
SINTER key [key ...]
- 示例：
redis> SADD key1 "a"
(integer) 1
redis> SADD key1 "b"
(integer) 1
redis> SADD key1 "c"
(integer) 1
redis> SADD key2 "c"
(integer) 1
redis> SADD key2 "d"
(integer) 1
redis> SADD key2 "e"
(integer) 1
redis> SINTER key1 key2
1) "c"
SINTERCARD
-
返回多个set相交的成员数。
-
语法：
SINTERCARD numkeys key [key ...] [LIMIT limit]
- 示例：
redis> SADD key1 "a"
(integer) 1
redis> SADD key1 "b"
(integer) 1
redis> SADD key1 "c"
(integer) 1
redis> SADD key1 "d"
(integer) 1
redis> SADD key2 "c"
(integer) 1
redis> SADD key2 "d"
(integer) 1
redis> SADD key2 "e"
(integer) 1
redis> SINTER key1 key2
1) "c"
2) "d"
redis> SINTERCARD 2 key1 key2
(integer) 2
redis> SINTERCARD 2 key1 key2 LIMIT 1
(integer) 1
SINTERSTORE
-
在一个key中存储多个set的相交。
-
语法：
SINTERSTORE destination key [key ...]
- 示例：
redis> SADD key1 "a"
(integer) 1
redis> SADD key1 "b"
(integer) 1
redis> SADD key1 "c"
(integer) 1
redis> SADD key2 "c"
(integer) 1
redis> SADD key2 "d"
(integer) 1
redis> SADD key2 "e"
(integer) 1
redis> SINTERSTORE key key1 key2
(integer) 1
redis> SMEMBERS key
1) "c"
SISMEMBER
-
确定成员是否属于set。
-
语法：
SISMEMBER key member
- 示例：
redis> SADD myset "one"
(integer) 1
redis> SISMEMBER myset "one"
(integer) 1
redis> SISMEMBER myset "two"
(integer) 0
SMEMBERS
-
返回set的所有成员。
-
语法：
SMEMBERS key
- 示例：
redis> SADD myset "Hello"
(integer) 1
redis> SADD myset "World"
(integer) 1
redis> SMEMBERS myset
1) "Hello"
2) "World"
SMISMEMBER
-
确定多个成员是否属于一个set。
-
语法：
SMISMEMBER key member [member ...]
- 示例：
redis> SADD myset "one"
(integer) 1
redis> SADD myset "one"
(integer) 0
redis> SMISMEMBER myset "one" "notamember"
1) (integer) 1
2) (integer) 0
SMOVE
-
将一个成员从一个set移动到另一个set。
-
语法：
SMOVE source destination member
- 示例：
redis> SADD myset "one"
(integer) 1
redis> SADD myset "two"
(integer) 1
redis> SADD myotherset "three"
(integer) 1
redis> SMOVE myset myotherset "two"
(integer) 1
redis> SMEMBERS myset
1) "one"
redis> SMEMBERS myotherset
2) "three"
3) "two"
SPOP
-
从set中删除一个或多个随机成员后返回它们。如果最后一个成员被弹出，则删除该set。
-
语法：
SPOP key [count]
- 示例：
redis> SADD myset "one"
(integer) 1
redis> SADD myset "two"
(integer) 1
redis> SADD myset "three"
(integer) 1
redis> SPOP myset
"one"
redis> SMEMBERS myset
1) "two"
2) "three"
redis> SADD myset "four"
(integer) 1
redis> SADD myset "five"
(integer) 1
redis> SPOP myset 3
3) "two"
4) "three"
5) "four"
redis> SMEMBERS myset
6) "five"
SRANDMEMER
-
从set中获取一个或多个随机成员
-
语法：
SRANDMEMBER key [count]
- 示例：
redis> SADD myset one two three
(integer) 3
redis> SRANDMEMBER myset
"two"
redis> SRANDMEMBER myset 2
1) "two"
2) "three"
redis> SRANDMEMBER myset -5
3) "three"
4) "one"
5) "three"
6) "two"
7) "three"
SREM
-
从set中删除一个或多个成员。如果最后一个成员被删除，则删除该set。
-
语法：
SREM key member [member ...]
- 示例：
redis> SADD myset "one"
(integer) 1
redis> SADD myset "two"
(integer) 1
redis> SADD myset "three"
(integer) 1
redis> SREM myset "one"
(integer) 1
redis> SREM myset "four"
(integer) 0
redis> SMEMBERS myset
1) "two"
2) "three"
SSCAN
-
遍历set的成员。
-
语法：
SSCAN key cursor [MATCH pattern] [COUNT count]
SUNION
-
返回多个set的并集。
-
语法：
SUNION key [key ...]
- 示例：
redis> SADD key1 "a"
(integer) 1
redis> SADD key1 "b"
(integer) 1
redis> SADD key1 "c"
(integer) 1
redis> SADD key2 "c"
(integer) 1
redis> SADD key2 "d"
(integer) 1
redis> SADD key2 "e"
(integer) 1
redis> SUNION key1 key2
1) "a"
2) "b"
3) "c"
4) "d"
5) "e"
SUNIONSTORE
-
将多个set的并集存储在一个key中。
-
语法：
SUNIONSTORE destination key [key ...]
- 示例：
redis> SADD key1 "a"
(integer) 1
redis> SADD key1 "b"
(integer) 1
redis> SADD key1 "c"
(integer) 1
redis> SADD key2 "c"
(integer) 1
redis> SADD key2 "d"
(integer) 1
redis> SADD key2 "e"
(integer) 1
redis> SUNIONSTORE key key1 key2
(integer) 5
redis> SMEMBERS key
1) "a"
2) "b"
3) "c"
4) "d"
5) "e"