SDIFF key [key ...]

Available since 1.0.0.

Time complexity: O(N) where N is the total number of elements in all given sets.

Returns the members of the set resulting from the difference between the first set and all the successive sets.

For example:

key1 = {a,b,c,d}
key2 = {c}
key3 = {a,c,e}
SDIFF key1 key2 key3 = {b,d}

Keys that do not exist are considered to be empty sets.

*Return value

Array reply: list with members of the resulting set.

*Examples

redis>  SADD key1 "a" 
(integer) 1
redis>  SADD key1 "b" 
(integer) 1
redis>  SADD key1 "c" 
(integer) 1
redis>  SADD key2 "c" 
(integer) 1
redis>  SADD key2 "d" 
(integer) 1
redis>  SADD key2 "e" 
(integer) 1
redis>  SDIFF key1 key2 
1) "a"
2) "b"
redis>