Uno R3 + Ethernet Shield W5100 + Project send and receive data to mysql

HI Guy

I am just to start learning with programming with Arduino. My project is send data command from Uno R3 to Hardware with RS-232 protocol and also sent the data to MySQL for keeping for update the data. For now I has attachment the my project to understand. Could you please provide me for the guideline and then I will try and leaning by myself. From attachment in the Item1,2 that part of communication from Arduino vs Hardware with serial comport RS-232 which example code that I can copy or leaning for adjust to my project and in the past item 3 that Arduino sent data that received from hardware to MySQL by internet Host so in this part not sure that I can leaning with the example on Webclient. Thank you for sharing something good to each other.