Returns the count of members in a sorted set that have scores within a range.
ZCOUNT
key min
max
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.
Integer reply: the number of members in the specified score range.
O(log(N)) with N being the number of elements in the sorted set.
@fast @read @sortedset
127.0.0.1:6379> ZADD myzset 1 "one"
(integer) 1
127.0.0.1:6379> ZADD myzset 2 "two"
(integer) 1
127.0.0.1:6379> ZADD myzset 3 "three"
(integer) 1
127.0.0.1:6379> ZCOUNT myzset -inf +inf
(integer) 3
127.0.0.1:6379> ZCOUNT myzset (1 3
(integer) 2
BZMPOP, BZPOPMAX, BZPOPMIN, ZADD, ZCARD, ZDIFF, ZDIFFSTORE, ZINCRBY, ZINTER, ZINTERCARD, ZINTERSTORE, ZLEXCOUNT, ZMPOP, ZMSCORE, ZPOPMAX, ZPOPMIN, ZRANDMEMBER, ZRANGE, ZRANGESTORE, ZRANK, ZREM, ZREMRANGEBYLEX, ZREMRANGEBYRANK, ZREMRANGEBYSCORE, ZREVRANK, ZSCAN, ZSCORE, ZUNION, ZUNIONSTORE.