ZINCRBY

    1. dragonfly> ZADD myzset 1 "one"
    2. dragonfly> ZADD myzset 2 "two"
    4. dragonfly> ZINCRBY myzset 2 "one"
    5. "3"
    6. 1) "two"
    7. 2) "2"
    8. 3) "one"