It's easier to follow what you are saying if you find your original post and use "Post a answer" to reply. That way readers can review previous messages on the subject to figure out what was said previously.
You don't need to return to Manage | Database just to get a summary field to update. Just change the value of the field that the summary field summarizes and commit the change. This can be as simple as clicking a blank area of the layout after editing a field. You can even click in the summary field column.
See this demo file and let me know if it's design is significantly different in any way: http://www.4shared.com/file/md2jPETJ/Summary_in_TableView.html