redis中value/SortedSet

默认物理内存左小右大，不随命令发生变化

zadd k1 8 apple 2 banana 3 orange

zrange k1 0 -1        banana orange apple

zrange k1 0 -1 withscores        banana 2 orange 3 apple 8
zrangebyscore k1 3 8        orange apple

zrange k1 0 1        banana orange

zrevrange k1 0 1        apple orange

zscore k1 apple        8        通过元素取出分值

zrank k1 apple          2        通过元素取出排名

zrange k1 0 -1        banana orange apple

zrange k1 0 -1 withscores        banana 2 orange 3 apple 8

zincrby k1 2.5 banana        4.5

zrange k1 0 -1 withscores        orange 3 banana 4.5 apple 8

zadd k1 80 s 60 ss 70 sss

zadd k2 60 s 100 ss 40 ssss

zunionstore unkey 2 k1 k2        

zrange unkey 0 -1 withscores        ssss 40 sss 70 s140 ss160

zunionstore unkey1 2 k1 k2 weights1 0.5

zrange unkey 0 -1 withscores         ssss 20 sss 70 s110 s110

zunionstore unkey1 2 k1 k2 aggregate max

zrange unkey1 0 -1 withscores        ssss 40 sss 70 s 80 ss 100

 排序是怎么实现的增删改查的速度？skip list 跳跃表 平均值相对最优