hello,
thank you for reply,

i main ex..

i have emp_no,emp_name,salary,overtime,total....etc

i insert emp_no,empname,salary(like300),overtime(like 25),
if i found something wrong at salary i updated to 350 ,when i pass to overtime
(on click or enter)to total ,the value change to 0 in overtime(textbox), i want to keep this value as its(25).