HMSET key field value [field value ...]
Time complexity: O(N) where N is the number of fields being set.
ACL categories: @write, @hash, @fast
Sets the specified fields to their respective values in the hash stored at
This command overwrites any specified fields already existing in the hash.
key does not exist, a new key holding a hash is created.
dragonfly> HMSET myhash field1 "Hello" field2 "World"
dragonfly> HGET myhash field1
dragonfly> HGET myhash field2