Hello Paul. Thanks for your advice. My strategy was based on "backup data once" approach but this would produce to many files I now realize.
But I still want to avoid to backup the entire database (N=0) on regular basis. Whats your opinion about this approach? First backup N=0 Every day N=1 for a month (replace file each time) Increment N next month. This would produce 12 files every year. Thanks, Hugo