redis hsetnx命令

HSETNX key field value

Sets field in the hash stored at key to value, only if field does not
yet exist.
If key does not exist, a new key holding a hash is created.
If field already exists, this operation has no effect.


Integer reply, specifically:

  • 1 if field is a new field in the hash and value was set.
  • 0 if field already exists in the hash and no operation was performed.


redis>  HSETNX myhash field “Hello”

(integer) 1

redis>  HSETNX myhash field “World”

(integer) 0

redis>  HGET myhash field