zset，有个有序的set集合，通过scores去确定优先级排序
1.添加，排序
127.0.0.1:6379> zadd dalielie 5000 g #添加元素到zset集合中
(integer) 1
127.0.0.1:6379> zadd dalielie 9000 c
(integer) 1
127.0.0.1:6379> zadd dalielie 10000 l
(integer) 1
127.0.0.1:6379> ZRANGEBYSCORE dalielie -inf +inf #从小到大排序输出
1) "g"
2) "c"
3) "l"
127.0.0.1:6379> ZRANGEBYSCORE dalielie -inf +inf withscores #从小到大排序输出并且附带元素值
1) "g"
2) "5000"
3) "c"
4) "9000"
5) "l"
6) "10000"
127.0.0.1:6379> ZREVRANGE dalielie 0 -1
1) "l"
2) "c"
127.0.0.1:6379> ZREVRANGE dalielie 0 -1 withscores #从大到小排序
1) "l"
2) "10000"
3) "c"
4) "9000"
127.0.0.1:6379>
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2，删除，展示
127.0.0.1:6379> zrange dalielie 0 -1 #指定范围展示元素
1) "g"
2) "c"
3) "l"
127.0.0.1:6379> zrem dalielie g #删除指定元素
(integer) 1
127.0.0.1:6379> zrange dalielie 0 -1
1) "c"
2) "l"
127.0.0.1:6379> zcard dalielie #查看集合中有多少值
(integer) 2
127.0.0.1:6379>
拓展：经典zset实用案例
1.做成绩排序
2.重要数据的话，做加权重的判断，比如排行榜相关业务