Save only one field to database which refereced to FieldFile

[3dflex@…]

django.db.models.fields.FieldFile:

def save(self, name, content, save=True):
....
    if save:
        self.instance.save(update_fields=[self.field.name])
....

or:

def save(self, name, content, save=True, **kwargs)
....
    if save:
        self.instance.save(**kwargs)
....

So, we get rid of re-saving fields when updating

[Łukasz Rekucki]

Option 1 is highly backwards incompatible and option 2 looks like an API bloat - passing save=False and calling instance.save() does exactly the same and avoids potential kwargs naming conflict.

[3dflex@…]

This is useful when you need to update the field contains id in the name(path), which can be obtained after the save. Now we can do:

def get_files_path(instance, filename):
    return os.path.join('files', str(instance.id), filename)

class MyFile(models.Model):
    ...
    file = models.FileField(upload_to=get_files_path)

model.save()
model.file.save(content.name, content)

The second query repeatedly update all fields, which is not acceptable when the data and fields to save is more.

Sorry for my English :)

[Jacob]

This ticket's effectively obsoleted by update_fields in Django 1.5 (​https://docs.djangoproject.com/en/dev/ref/models/instances/#specifying-which-fields-to-save).

[3dflex@…]

There is no such option in FieldFile.save (​https://docs.djangoproject.com/en/dev/ref/models/fields/#django.db.models.fields.files.FieldFile.save)

[Alex Gaynor]

Marking as accepted, the ability to not save all the things makes sense. Not sure if it should be the default or an option yet.

[anonymous]

As the expected release of Django 1.6, can we see this feature in it?

[Tim Graham]

The reason this was originally closed is because you can do this:

obj.file.save(content.name, content, save=False)
obj.save(update_fields=['file'])

This seems acceptable to me.