SDIFFSTORE
Syntax
SDIFFSTORE destination key [key ...]
Time complexity: O(N) where N is the total number of elements in all given sets.
This command is equal to SDIFF, but instead of returning the resulting set, it
is stored in destination.
If destination already exists, it is overwritten.
Return
Integer reply: the number of elements in the resulting set.
Examples
dragonfly> SADD key1 "a"
(integer) 1
dragonfly> SADD key1 "b"
(integer) 1
dragonfly> SADD key1 "c"
(integer) 1
dragonfly> SADD key2 "c"
(integer) 1
dragonfly> SADD key2 "d"
(integer) 1
dragonfly> SADD key2 "e"
(integer) 1
dragonfly> SDIFFSTORE key key1 key2
(integer) 2
dragonfly> SMEMBERS key
1) "b"
2) "a"