FOREIGN KEY constraint failed in signals - django

Question

I tried to insert data into the table Account, but I keep getting this error message.
I delete all my migrations and make migrations again but I keep getting this error.
Here is my models.
class Student(models.Model):
user = models.OneToOneField(Account, on_delete=models.CASCADE)
name = models.CharField(max_length=50, null=True, blank=True)
phone = models.CharField(max_length=15, blank=True, null=True)
gender = models.CharField(max_length=1, choices=GENDER_CHOICES, blank=True, null=True)
section = models.ForeignKey(Section, on_delete=models.CASCADE, default=1)
dept = models.ForeignKey(Dept, on_delete=models.CASCADE, blank=True, null=True)
batch = models.CharField(max_length=15, null=True, blank=True)
USN = models.CharField(primary_key='True', max_length=100)
DOB = models.DateField(default='1998-01-01')
profile_image = models.ImageField(upload_to='student/profile_images/%Y/%m/%d/', blank=True, null=True)
address = models.CharField(max_length=300, null=True, blank=True)
nationality = models.CharField(max_length=100, null=True, blank=True)
guardian_name = models.CharField(max_length=200, null=True, blank=True)
guardian_number = models.CharField(max_length=15, null=True, blank=True)
guardian_address = models.CharField(max_length=300, null=True, blank=True)
blood_group = models.CharField(max_length=3, null=True, blank=True)
exam_name = models.CharField(max_length=300, null=True, blank=True)
background = models.CharField(max_length=300, null=True, blank=True)
passing_year = models.CharField(max_length=8, null=True, blank=True)
score = models.CharField(max_length=10, null=True, blank=True)
school_name = models.CharField(max_length=300, null=True, blank=True)
country = models.CharField(max_length=100, null=True, blank=True)
certificate = models.FileField(upload_to='certificates/%Y/%m/%d/', null=True, blank=True)
Here is Account model.
class Account(AbstractBaseUser, PermissionsMixin):
unid = models.CharField(max_length=20, unique=True, null=True, blank=True)
email = models.EmailField(verbose_name="email", max_length=60, unique=True)
username = models.CharField(max_length=30, unique=True)
is_admin = models.BooleanField(default=False)
is_active = models.BooleanField(default=True)
is_staff = models.BooleanField(default=False)
is_superuser = models.BooleanField(default=False)
is_student = models.BooleanField(default=False)
is_teacher = models.BooleanField(default=False)
group = models.ForeignKey(Group, on_delete=models.CASCADE, null=True, blank=True)
user_permissions = models.ManyToManyField(
Permission,
verbose_name=_('user permissions'),
blank=True,
null=True,
help_text=_('Specific permissions for this user.'),
related_name="user_set",
related_query_name="user",
)
date_joined = models.DateTimeField(verbose_name='date joined', auto_now_add=True)
last_login = models.DateTimeField(verbose_name='last login', auto_now=True)
registered = models.BooleanField(default=False)
so what I did is that when I create account if the is_student is True I create a signals that going to create student model for that account instance automatically.
here is the signals
def create_student_or_teacher(sender, created, instance, **kwargs):
if created:
if instance.is_student:
Student.objects.create(
user=instance,
USN=instance.unid,
)
elif instance.is_teacher:
Teacher.objects.create(
user=instance,
id=instance.unid,
)
So when I create the account for student the tracker will highlight in the signals Student.objects.create(...)
If you have any idea I hope it would help me.
UPDATED:
When I'm creating teacher it is working find.
here is the teacher model
class Teacher(models.Model):
name = models.CharField(max_length=50, null=True, blank=True)
phone = models.CharField(max_length=15, blank=True, null=True)
gender = models.CharField(max_length=1, choices=GENDER_CHOICES, blank=True)
salary = models.IntegerField(default=1)
school = models.ForeignKey(School, blank=True, null=True, on_delete=models.CASCADE)
section = models.ForeignKey(Section, blank=True, null=True, on_delete=models.CASCADE)
user = models.OneToOneField(Account, on_delete=models.CASCADE, null=True)
id = models.CharField(primary_key=True, max_length=100)
dept = models.ForeignKey(Dept, on_delete=models.CASCADE, blank=True, null=True)
DOB = models.DateField(default='1980-01-01')
profile_image = models.ImageField(upload_to='teacher/profile_images/%Y/%m/%d/', blank=True, null=True)
nationality = models.CharField(max_length=300, null=True, blank=True)
address = models.CharField(max_length=300, null=True, blank=True)

Answer 1

Finally after few hours I solved my error it was simple
in the section I set default value which was not exist
so I just change the value to an exist one and that was it.