I need your help. I have been doing invitee management system. In this system, user can add, update,view and delete the data. I have used SQL to connect to database. The system I did is quite messed up$.$ I need a clean code with comments in it and workable code. I cannot perform group delete, please give code for that as well. Please give the entire code with methods and event handler code. I attach the code that I have done so far. Modify my code.