I have the following model
@python_2_unicode_compatible
class Booking(models.Model):
session = models.ForeignKey(verbose_name=_('Session'), to=Session, default=None, null=False, blank=False)
quantity = models.PositiveIntegerField(verbose_name=_('Quantity'), default=1, null=False, blank=False)
price = models.DecimalField(verbose_name=_('Price'), max_digits=10, decimal_places=2,
default=None, null=False, blank=False)
name = models.CharField(verbose_name=_('Name'), max_length=100, default=None, null=False, blank=False)
email = models.EmailField(verbose_name=_('Email'), default=None, null=True, blank=True)
phone_number = models.CharField(verbose_name=_('Phone Number'), max_length=30, default=None, null=True, blank=True)
Say I need to change my email and phone_number fields. I want them to have null=False and blank=False. Do these alterations require a new migration?
Yes they do. null=False requires a change to the database schema itself; blank=False does not, but Django needs a migration anyway so that the migration runner's internal graph of the model state is up to date.
Sure. To check it you can run python manage.py makemigrations --dry-run (the --dry-run doesn't save a new migration file, but shows if it's necessary)
https://docs.djangoproject.com/en/1.11/topics/db/models/#field-options
Django document says:
null
If True, Django will store empty values as NULL in the database. Default >is False.
blank
If True, the field is allowed to be blank. Default is False.
Note that this is different than null. null is purely database-related, whereas blank is validation-related. If a field has blank=True, form validation will allow entry of an empty value. If a field has blank=False, the field will be required.
For change in null you need to migrate
For change in blank you need not to migrate, because its admin form related