ZRANK key member

Available since 2.0.0.

Time complexity: O(log(N))

Returns the rank of member in the sorted set stored at key, with the scores ordered from low to high. The rank (or index) is 0-based, which means that the member with the lowest score has rank 0.

Use ZREVRANK to get the rank of an element with the scores ordered from high to low.

*Return value

• If member exists in the sorted set, Integer reply: the rank of member.
• If member does not exist in the sorted set or key does not exist, Bulk string reply: nil.

*Examples

redis> ZADD myzset 1 "one"

(integer) 1

redis> ZADD myzset 2 "two"

(integer) 1

redis> ZADD myzset 3 "three"

(integer) 1

redis> ZRANK myzset "three"

(integer) 2

redis> ZRANK myzset "four"

(nil)