4.set类型以及操作

set是集合，它是string类型的无序集合 

set是通过hash table实现的， 

添加、删除和查找的复杂度都是0(1) 

对集合我们可以取交集、并集、差集 

通过这些操作我们可以实现SNS中的好友推荐和blog的tag功能 

sadd

向名称为key的set中添加元素 

redis 127.0.0.1:6379> sadd myset "hello" (integer) 1 redis 127.0.0.1:6379> sadd myset "world" (integer) 1 redis 127.0.0.1:6379> sadd myset "world" (integer) 0 redis 127.0.0.1:6379> smembers myset 1) "world" 2) "hello" 

smembers

获取名称为key的set中所有元素 

redis 127.0.0.1:6379> smembers myset 1) "hello" 1) "world" 

srem

删除名称为key的set中的元素 

redis 127.0.0.1:6379> sadd myset2 "one" (integer) 1 redis 127.0.0.1:6379> sadd myset2 "two" (integer) 1 redis 127.0.0.1:6379> srem myset2 "one" (integer) 1 

spop

随机返回并删除名称为key的set中一个元素 

redis 127.0.0.1:6379> sadd myset3 "one" (integer) 1 redis 127.0.0.1:6379> sadd myset3 "two" (integer) 1 redis 127.0.0.1:6379> spop myset3 "two" 

sdiff

返回所有给定key与第一个key的差集 

redis 127.0.0.1:6379> smembers myset2 1) "three" 2) "two" redis 127.0.0.1:6379> smembers myset3 1) "two" 2) "one" redis 127.0.0.1:6379> sdiff myset2 myset3 1) "three" 

sdiffstore

返回所有给定key与第一个key的差集，并将结果存为另一个key 

redis 127.0.0.1:6379> smembers myset2 1) "three" 2) "two" redis 127.0.0.1:6379> smembers myset3 1) "two" 2) "one" redis 127.0.0.1:6379> sdiffstore myset4 myset2 myset3 (integer) 1 redis 127.0.0.1:6379> smembers myset4 1) "three" 

sinter

返回所有给定key的交集 

redis 127.0.0.1:6379> smembers myset2 1) "three" 2) "two" redis 127.0.0.1:6379> smembers myset3 1) "two" 2) "one" redis 127.0.0.1:6379> sinter myset2 myset3 1) "two" 

sinterstore

返回所有给定key的交集，并将结果存为另一个key 

redis 127.0.0.1:6379> smembers myset2 1) "three" 2) "two" redis 127.0.0.1:6379> smembers myset3 1) "two" 2) "one" redis 127.0.0.1:6379> sinterstore myset4 myset2 myset3 (integer) 1 redis 127.0.0.1:6379> smembers myset4 1) "two"

sunion

返回所有给定key的并集 

redis 127.0.0.1:6379> smembers myset2 1) "three" 2) "two" redis 127.0.0.1:6379> smembers myset3 1) "two" 2) "one" redis 127.0.0.1:6379> sunion myset2 myset3 1) "three" 2) "one" 3) "two"  

sunionstore

返回所有给定key的并集 

redis 127.0.0.1:6379> smembers myset2 1) "three" 2) "two" redis 127.0.0.1:6379> smembers myset3 1) "two" 2) "one" redis 127.0.0.1:6379> sunionstore myset 4 myset2 myset3 (integer) 3 redis 127.0.0.1:6379> smembers myset4 1) "three" 2) "one" 3) "two" 

smove

从第一个key对应的set中移除member并添加到第二个对应的set中 

redis 127.0.0.1:6379> smembers myset2 1) "three" 2) "two" redis 127.0.0.1:6379> smembers myset3 1) "three" 2) "one" redis 127.0.0.1:6379> smove myset2 myset7 three (integer) 1 redis 127.0.0.1:6379> smembers myset2 1) "two" redis 127.0.0.1:6379> smembers myset7 1) "three" 

scard

返回名称为key的set的元素个数 

redis 127.0.0.1:6379> scard myset2 (integer) 1 

sismember

测试member是否是名称为key的set的元素 

redis 127.0.0.1:6379> smembers myset2 1) "two" redis 127.0.0.1:6379> sismember myset2 two (integer) 1 redis 127.0.0.1:6379> sismember myset2 one (integer) 0 

srandmember

随机返回名称为key的set的一个元素，但不删除元素 

redis 127.0.0.1:6379> smembers myset3 1) "two" 2) "one" redis 127.0.0.1:6379> srandmember myset3 "two" redis 127.0.0.1:6379> srandmember myset3 "one" 

5.sorted sets类型以及操作

sorted set 是set的一个升级版本，它在set的基础上增加了一个顺序属性 

这一属性在添加修改元素的时候可以指定 

每次指定后，zset会自动重新按新的值调整顺序 

可以理解为有两列的MySQL表，一列存value，一列存顺序，操作中key理解为zset的名字 

zadd

向名称为key的zset中添加元素member，score用于排序，如果该元素存在，则更新其顺序 

redis 127.0.0.1:6379> zadd myzset 1 "one" (integer) 1 redis 127.0.0.1:6379> zadd myzset 2 "two" (integer) 1 redis 127.0.0.1:6379> zadd myzset 3 "two" // 添加未成功，但是顺序号更新 

(integer) 0 

redis 127.0.0.1:6379> zrange myzset 0 -1 withscores // withscores 输出顺序号 

1) "one" 

2) "1" 

3) "two" 

4) "3" 

zrem

删除名称为key的zset中的元素member 

redis 127.0.0.1:6379> zrange myzset 0 -1 withscores 1) "one" 2) "1" 3) "two" 4) "3" redis 127.0.0.1:6379> zrem myzset two (integer) 1 redis 127.0.0.1:6379> zrange myzset 0 -1 withscores 1) "one" 2) "1" 

zincrby

如果再名称为key的zset中已经存在元素member，则该元素的score增加increment 

否则向该集合中添加该元素，其score的值为increment 

redis 127.0.0.1:6379> zadd myzset2 1 "one" 

(integer) 1 

redis 127.0.0.1:6379> zadd myzset2 2 "two" 

(integer) 1 

redis 127.0.0.1:6379> zincrby myzset2 2 "one" 

"3" 

redis 127.0.0.1:6379> zrange myzset2 0 -1 withscores 

1) "two" 

2) "2" 

3) "one" 

4) "3" 

zrank

返回名称为key的zset中member元素的排名（按score从小到大排序）即下标 

redis 127.0.0.1:6379> zrange myzset3 0 -1 withscores 

1) "one" 2) "1" 3) "two" 4) "2" 5) "three" 6) "3" 7) "five" 8) "5" redis 127.0.0.1:6379> zrank myzset3 two (integer) 1 

zrevrank

返回名称为key的zset中member元素的排名（按score从大到小排序）即下标 

redis 127.0.0.1:6379> zrange myzset3 0 -1 withscores 1) "one" 2) "1" 3) "two" 4) "2" 5) "three" 6) "3" 7) "five" 8) "5" redis 127.0.0.1:6379> zrevrank myzset3 two (integer) 2

zrevrange 

返回名称为key的zset（按score从大到小顺序）中的index从start到end的所有元素 

redis 127.0.0.1:6379> zrevrange myzset3 0 -1 withscores 

1) "five" 

2) "5" 

3) "three" 

4) "3" 

5) "two" 

6) "2" 

7) "one" 

8) "1"  

zrangebyscore

返回集合中score在给定区间的元素 

redis 127.0.0.1:6379> zrange myzset3 0 -1 withscores 1) "one" 2) "1" 3) "two" 4) "2" 5) "three" 6) "3" redis 127.0.0.1:6379> zrangebyscore myzset3 2 3 withscores 1) "two" 2) "2" 3) "three" 4) "3" 

zcount

返回集合中score在给定区间的数量 

redis 127.0.0.1:6379> zrange myzset3 0 -1 withscores 1) "one" 2) "1" 3) "two" 4) "2" 5) "three" 6) "3" 7) "five" 8) "5" redis 127.0.0.1:6379> zcount myzset3 2 3 (integer) 2 

zcard

返回所有元素个数 

redis 127.0.0.1:6379> zcard myzset3 (integer) 4 

zremrangebyrank

删除集合中排名在给定区间的元素 

redis 127.0.0.1:6379> zrange myzset3 0 -1 withscores 1) "one" 2) "1" 3) "two" 4) "2" redis 127.0.0.1:6379> zremrangebyrank myzset3 1 1  (integer) 1 redis 127.0.0.1:6379> zrange myzset3 0 -1 withscores 1) "one" 2) "1" 

zremrangebyscore

删除集合中score在给定区间的元素 

redis 127.0.0.1:6379> zrange myzset3 0 -1 withscores 1) "one" 2) "1" 3) "two" 4) "2" 5) "three" 6) "3" redis 127.0.0.1:6379> zremrangebyscore myzset3 1 2 (integer) 2 redis 127.0.0.1:6379> zrange myzset3 0 -1 withscores 1) "three" 2) "3"