IntegrityError: null value in column violates NOT NULL constraint

IntegrityError: null value in column violates NOT NULL constraint

$ python manage.py shell -c "from app.models import Item; Item.objects.create(name=None)"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
IntegrityError: null value in column "name" violates not-null constraint

Why this happens

Field is defined with null=False and the database rejects NULLs when you try to save one.

Fix

Provide a value, set defaults, or adjust field to allow nulls.

Wrong code

class Item(models.Model):
    name = models.CharField(max_length=100)

Item.objects.create(name=None)

Fixed code

class Item(models.Model):
    name = models.CharField(max_length=100, null=True, blank=True)  # if acceptable

Item.objects.create(name="Test")