SortedSet数据结构

ZSET认识

备注

A Redis sorted set is a collection of unique strings (members) ordered by an associated score. When more than one string has the same score, the strings are ordered lexicographically. Some use cases for sorted sets include:

• Leaderboards. For example, you can use sorted sets to easily maintain ordered lists of the highest scores in a massive online game.
• Rate limiters. In particular, you can use a sorted set to build a sliding-window rate limiter to prevent excessive API requests.

ZADD 添加元素

ZADD key [NX | XX] [GT | LT] [CH] [INCR] score member [score member ...]

• XX：仅更新已存在的元素。不添加新元素。
• NX：仅添加新元素。不更新已经存在的元素。
• LT：仅当新分数小于当前分数时才更新现有元素。此标志不会阻止添加新元素。
• GT：仅当新分数大于当前分数时才更新现有元素。此标志不会阻止添加新元素。
• CH：将返回值从新添加的元素数修改为已更改的元素总数（CH 是“已更改”的缩写）。已更改的元素包括新添加的元素和已更新分数的现有元素。因此，命令行中指定的分数与过去相同的元素不计算在内。注意：通常的返回值ZADD仅计算新添加的元素数。
• INCR : 指定此选项时，ZADD其作用类似于ZINCRBY。在此模式下，只能指定一个分数元素对。

Redis Command

 127.0.0.1:6379> ZADD zset:001 60 v1 70 v2 80 v3
 (integer) 1

Java

    redisTemplate.opsForZSet().add("zset1","v1",70);

ZRANGE 查看元素

从小到大查看元素

Redis Command

 127.0.0.1:6379> ZRANGE zset:001 0 -1
1) "v1"
2) "v2"
3) "v3"

Java

    redisTemplate.opsForZSet().range("zset1",0,-1);

ZREVRANGE 查看元素

从大到小查看元素

Redis Command

 127.0.0.1:6379> ZREVRANGE zset:001 0 -1
1) "v3"
2) "v2"
3) "v1"

Java

    redisTemplate.opsForZSet().reverseRange("zset1",0,-1);

ZCARD 获取元素数量

Redis Command

 127.0.0.1:6379> ZCARD zset:001
 (integer) 3

Java

            redisTemplate.opsForZSet().zCard("zset1");

ZSCORE 获取元素分数

Redis Command

 localhost:6379> ZSCORE zset1 v1
 "60"

Java

    redisTemplate.opsForZSet().score("zset1","v1");

ZREM 删除元素

Redis Command

localhost:6379> ZREM zset1 v1
 (integer) 1

Java

    redisTemplate.opsForZSet().remove("zset1","v1");