Greetings. I am using MS VISTA and Excel 2007 (I am a relative newcomer).

I was wondering if I can create a (Primary) Key column (or whatever it's
called), so that I can resort the spreadsheet back to the original order /
sequence (that is, after I make some revisions / updates in certain cells).

The problem arises when I have to insert new rows, which create gaps in the
column I am currently using (it is simply a column with a numbered sequence
1-about 700000!). How can this be done? And please explain in very simple
English. Thank you.