ZCOUNT
Syntax
ZCOUNT key min max
Time complexity: O(log(N)) with N being the number of elements in the sorted set.
Returns the number of elements in the sorted set at key
with a score between
min
and max
.
The min
and max
arguments have the same semantic as described for
ZRANGEBYSCORE
.
Note: the command has a complexity of just O(log(N)) because it uses elements ranks (see ZRANK
) to get an idea of the range. Because of this there is no need to do a work proportional to the size of the range.
Return
Integer reply: the number of elements in the specified score range.
Examples
dragonfly> ZADD myzset 1 "one"
(integer) 1
dragonfly> ZADD myzset 2 "two"
(integer) 1
dragonfly> ZADD myzset 3 "three"
(integer) 1
dragonfly> ZCOUNT myzset -inf +inf
(integer) 3
dragonfly> ZCOUNT myzset (1 3
(integer) 2