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ZLEXCOUNT

Returns the number of members in a sorted set within a lexicographical range.

Usage
ZLEXCOUNT key min max
Complexity
O(log(N)) with N being the number of elements in the sorted set.
Since
2.8.9
ACL Categories
@fast, @read, @sortedset
Command flags
READONLY, FAST

When all the elements in a sorted set are inserted with the same score, in order to force lexicographical ordering, this command returns the number of elements in the sorted set at key with a value between min and max.

The min and max arguments have the same meaning as described for ZRANGEBYLEX.

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.

Examples

127.0.0.1:6379> ZADD myzset 0 a 0 b 0 c 0 d 0 e
(integer) 5
127.0.0.1:6379> ZADD myzset 0 f 0 g
(integer) 2
127.0.0.1:6379> ZLEXCOUNT myzset - +
(integer) 7
127.0.0.1:6379> ZLEXCOUNT myzset [b [f
(integer) 5

Replies

RESP2

Integer reply: the number of members in the specified score range.

RESP3

Integer reply: the number of members in the specified score range.