Redis的Set操作

集合的性质: 唯一性,无序性,确定性

注: 在string和link的命令中,可以通过range 来访问string中的某几个字符或某几个元素

但,因为集合的无序性,无法通过下标或范围来访问部分元素.

因此想看元素,要么随机先一个,要么全选

sadd key value1 value2
作用: 往集合key中增加元素
127.0.0.1:6379> sadd gender male female
(integer) 2
127.0.0.1:6379> sadd gender yao yao
(integer) 1
127.0.0.1:6379> sadd gender yao
(integer) 0

smembers key
作用: 返回集中中所有的元素
127.0.0.1:6379> smembers gender
1) "male"
2) "female"
3) "yao"

srem value1 value2
作用: 删除集合中集为 value1 value2的元素
返回值: 忽略不存在的元素后,真正删除掉的元素的个数
127.0.0.1:6379> srem gender yao
(integer) 1
127.0.0.1:6379> srem gender x c
(integer) 0
127.0.0.1:6379> srem gender male x c
(integer) 1

spop key//抽奖
作用: 返回并删除集合中key中1个随机元素
随机--体现了无序性
127.0.0.1:6379> sadd gender a b c d e f
(integer) 6
127.0.0.1:6379> smembers gender
1) "d"
2) "c"
3) "a"
4) "f"
5) "female"
6) "b"
7) "e"
127.0.0.1:6379> spop gender
"a"
127.0.0.1:6379> smembers gender
1) "d"
2) "c"
3) "f"
4) "female"
5) "b"
6) "e"
127.0.0.1:6379> spop gender
"c"
127.0.0.1:6379> spop gender
"f"
127.0.0.1:6379> spop gender
"e"

srandmember key
作用: 返回集合key中,随机的1个元素.
127.0.0.1:6379> smembers gender
1) "d"
2) "c"
3) "a"
4) "f"
5) "female"
6) "e"
7) "b"
127.0.0.1:6379> srandmember gender
"female"
127.0.0.1:6379> srandmember gender
"f"
127.0.0.1:6379> srandmember gender
"c"
127.0.0.1:6379> srandmember gender
"c"
127.0.0.1:6379> srandmember gender
"a"
127.0.0.1:6379> srandmember gender
"d"

sismember key  value
作用: 判断value是否在key集合中
是返回1,否返回0
127.0.0.1:6379> smembers gender
1) "d"
2) "c"
3) "a"
4) "f"
5) "female"
6) "e"
7) "b"
127.0.0.1:6379> sismember gender q
(integer) 0
127.0.0.1:6379> sismember gender f
(integer) 1

scard key
作用: 返回集合中元素的个数127.0.0.1:6379> scard gender(integer) 7

smove source dest value
作用:把source中的value删除,并添加到dest集合中
127.0.0.1:6379> sadd upper A B C
(integer) 3
127.0.0.1:6379> sadd lower a b c
(integer) 3
127.0.0.1:6379> smove upper lower A
(integer) 1
127.0.0.1:6379> smembers upper
1) "C"
2) "B"
127.0.0.1:6379> smembers lower
1) "c"
2) "A"
3) "b"
4) "a"

sinter  key1 key2 key3
作用: 求出key1 key2 key3 三个集合中的交集,并返回
sinterstore dest key1 key2 key3
作用: 求出key1 key2 key3 三个集合中的交集,并赋给dest
suion key1 key2.. Keyn
作用: 求出key1 key2 keyn的并集,并返回
127.0.0.1:6379> sadd lisi a b c d
(integer) 4
127.0.0.1:6379> sadd wang a c d e f
(integer) 5
127.0.0.1:6379> sadd poly a c d g
(integer) 4
127.0.0.1:6379> sinter lisi wang poly
1) "d"
2) "c"
3) "a"
127.0.0.1:6379> sinterstore common lisi wang poly
(integer) 3
127.0.0.1:6379> smembers common
1) "d"
2) "c"
3) "a"
127.0.0.1:6379> sunion lisi wang poly
1) "d"
2) "g"
3) "c"
4) "a"
5) "f"
6) "e"
7) "b"

sdiff key1 key2 key3
作用: 求出key1与key2 key3的差集
即key1-key2-key3
127.0.0.1:6379> sdiff lisi wang poly
1) "b"