[the_callant]

Is there a simple way to automatically add or change a date within calibre. I have created a custom column which gives the date that a book is added to my Calibre Library. I have been manually entering this date when I have added books, so I now have a column where sometimes there is a date, but sometimes it is blank. Is there a way of setting up a script which would check if the field was empty, then copy across the existing date field content if it is empty and automatically set the date added to the todays date when I add the book?
The first question really is can it be done?
If it can is there a prewritten script or where would i look to try and create one?