I read the document <https://docs.djangoproject.com/en/1.11/ref/models/fields/#null> about field options 'null'.
It is said that. If True, Django will store empty values as NULL in the database. Default is > False. > > Avoid using null > <https://docs.djangoproject.com/en/1.11/ref/models/fields/#django.db.models.Field.null> > on > string-based fields such as CharField > <https://docs.djangoproject.com/en/1.11/ref/models/fields/#django.db.models.CharField> > and TextField > <https://docs.djangoproject.com/en/1.11/ref/models/fields/#django.db.models.TextField>. > > If a string-based field has null=True, that means it has two possible > values for “no data”: NULL, and the empty string. > Then I try make a field have "null=True", just save it to database. like that. >>> from backend.models import Scrapyd as S >>> s = S() >>> s.comment >>> type(s.comment) <class 'NoneType'> >>> s.save() >>> b = S.objects.all().last() >>> b <Scrapyd: Scrapyd object> >>> b.comment >>> type(b.comment) <class 'NoneType'> *What my question is why the value not like the document <https://docs.djangoproject.com/en/1.11/ref/models/fields/#null>said is empty string ''?* *I am confused.* -- You received this message because you are subscribed to the Google Groups "Django users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/django-users. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/1b239340-78d6-4df2-a12d-9531dfe7912d%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
