ZRANK
Syntax
ZRANK key member
Time complexity: O(log(N))
ACL categories: @read, @sortedset, @fast
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
.
The optional WITHSCORE
argument supplements the command’s reply with the score of the element returned.
Use ZREVRANK
to get the rank of an element with the scores ordered from high to low.
Return
- If
member
exists in the sorted set Integer reply: the rank ofmember
. - If
member
does not exist in the sorted set orkey
does not exist Bulk string reply:nil
.
Examples
dragonfly> ZADD myzset 1 "one"
(integer) 1
dragonfly> ZADD myzset 2 "two"
(integer) 1
dragonfly> ZADD myzset 3 "three"
(integer) 1
dragonfly> ZRANK myzset "three"
(integer) 2
dragonfly> ZRANK myzset "four"
(nil)