HLEN – Redis

Available since 2.0.0.

时间复杂度： O(1)

Returns the number of fields contained in the hash stored at key.

返回值

Integer reply: number of fields in the hash, or 0 when key does not exist.

redis> HSET myhash field1 "Hello"

(integer) 1

redis> HSET myhash field2 "World"

(integer) 1

redis> HLEN myhash

(integer) 2