Detect if a model has changed before calling save in Django

Question

I have a database model that is being updated based on changes in remote data (via an HTML scraper).

I want to maintain a field called changed - a times

Answer 1

Sounds to me like what you want is Signals: http://docs.djangoproject.com/en/1.2/topics/signals/

You could use a post_save signal to update a related field in another model to store the previous value. Then on the next go-round you'd have something to compare.