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
Use ZREVRANK to get the rank of an element with the scores ordered from high to low.
memberexists in the sorted set, Integer reply: the rank of
memberdoes not exist in the sorted set or
keydoes not exist, Bulk string reply:
(integer) 1redis> ZADD myzset 2 "two"
(integer) 1redis> ZADD myzset 3 "three"
(integer) 1redis> ZRANK myzset "three"
(integer) 2redis> ZRANK myzset "four"