ZDIFFSTORE

ZDIFFSTORE destination numkeys key [key ...]

#Example

redis> ZADD zset1 1 "one"
(integer) 1
redis> ZADD zset1 2 "two"
(integer) 1
redis> ZADD zset1 3 "three"
(integer) 1
redis> ZADD zset2 1 "one"
(integer) 1
redis> ZADD zset2 2 "two"
(integer) 1
redis> ZDIFFSTORE out 2 zset1 zset2
(integer) 1
redis> ZRANGE out 0 -1 WITHSCORES
1) "three"
2) "3"

Subtract multiple sorted sets and store the resulting sorted set in a new key