HLEN
HLEN key
Returns the number of fields contained in the hash stored at key.
Return value
Integer reply: number of fields in the hash, or 0 when key does not exist.
Examples
 redis>  HSET myhash field1 "Hello" 
  (integer) 1 redis>  HSET myhash field2 "World" (integer) 1 redis>  HLEN myhash (integer) 2
    © 2009–2020 Salvatore Sanfilippo
Licensed under the Creative Commons Attribution-ShareAlike License 4.0.
    https://redis.io/commands/hlen