SMISMEMBER – Redis

Available since 6.2.0.

Time complexity: O(N) where N is the number of elements being checked for membership

Returns whether each member is a member of the set stored at key.

For every member, 1 is returned if the value is a member of the set, or 0 if the element is not a member of the set or if key does not exist.

*Return value

Array reply: list representing the membership of the given elements, in the same order as they are requested.

redis> SADD myset "one"

(integer) 1

redis> SADD myset "one"

(integer) 0

redis> SMISMEMBER myset "one" "notamember"

1) (integer) 1
2) (integer) 0