作者：Grey
原文地址: Redis学习笔记三：Redis有序集的基本使用和底层实现
我们可以使用Redis中的sorted_set对数据进行排序。
基本用法
#有序集
#sorted_set
#Z开头的命令,ZADD,ZCOUNT
zadd fruit 8 apple 2 banana 3 orange
zrange fruit 0 -1
1) "banana"
2) "orange"
3) "apple"
zrange fruit 0 -1 withscores
1) "banana"
2) "2"
3) "orange"
4) "3"
5) "apple"
6) "8"
zcount fruit 3 8
(integer) 2
zscore fruit apple
"8"
#价格由低到高取出前两位
zarange k1 0 1
#价格由高到低取出前两位
zrevarange k1 0 1
zscore fruit apple
"8"
zrank fruit banana
0
zincrby fruit 2.5 banana
"4.5"
127.0.0.1:6379> zadd k1 2 a 3 b 4 c
(integer) 3
127.0.0.1:6379> zadd k2 3 a 1 b 2 c
(integer) 3
127.0.0.1:6379> ZUNIONSTORE k4 2 k1 k2
(integer) 3
127.0.0.1:6379> zrange k4 0 -1
1) "b"
2) "a"
3) "c"
127.0.0.1:6379> ZUNIONSTORE k4 2 k1 k2 aggregate sum
(integer) 3
127.0.0.1:6379> zrange k4 0 -1
1) "b"
2) "a"
3) "c"
127.0.0.1:6379> ZUNIONSTORE k4 2 k1 k2 aggregate max
(integer) 3
127.0.0.1:6379> zrange k4 0 -1
1) "a"
2) "b"
3) "c"
127.0.0.1:6379> ZUNIONSTORE k4 2 k1 k2 aggregate min
(integer) 3
127.0.0.1:6379> zrange k4 0 -1
1) "b"
2) "a"
3) "c"
更多命令见：Redis学习笔记二：基本命令与使用场景
sorted_set的底层实现–跳表
关于跳表，我这里写了一篇文章详细介绍了一下跳表的实现细节：LeetCode 1206. Design Skiplist
参考资料
Skip Lists: A Probabilistic Alternative to Balanced Trees (1990)