How to get last IP address of DB update request ? I have a MySql Database hosted in the cloud. 

From an embedded device connected to the Internet network via an ISP  I write some values (coming from a sensor) in a table of this Database.

Is it possible to know the last IP address of the embedded device  by querying the DB ?
No.

The file access.log contains connections, but that is not accessible via SQL.  (And your hosting service may not let you access that file.)