When saving, how can you check if a field has changed?

Question

In my model I have :

class Alias(MyBaseModel):
    remote_image = models.URLField(max_length=500, null=True, help_text=\"A URL that is downloaded and cached          


        

Answer 1

As of Django 1.8, there's the from_db method, as Serge mentions. In fact, the Django docs include this specific use case as an example:

https://docs.djangoproject.com/en/dev/ref/models/instances/#customizing-model-loading

Below is an example showing how to record the initial values of fields that are loaded from the database