What is it that you are storing? As an example, let say the you are storing employee addresses, you can create a table that contains two columns, one with the employee's name (or ID) and another column called "last_updated". Everytime you make a change in the form (ex: when clicking the save button), in your code you edit the record containing the last_updated value to equal the current date (you can get the current date by using the Now() function).
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