[FIXED] django.db.utils.ProgrammingError: multiple default values specified for column "id" of table "products_customer"

Issue

After make migrations , i tried to do migrate, but i am getting the django.db.utils.ProgrammingError: multiple default values specified for column "id" of table "products_customer"

But iam remove this customer table from models.py how i solve this ?

models.py

from django.db import models
from django.contrib.auth.models import User
from django.db.models.signals import post_save
from django.dispatch import receiver



# Create your models here.

class product(models.Model):
    product_id = models.IntegerField(primary_key=True)
    product_name = models.CharField(max_length=255)
    product_price = models.FloatField()
    product_stock = models.IntegerField()
    product_image = models.CharField(max_length=2500)



class order(models.Model):
    order_id = models.IntegerField(primary_key=True)
    product_id = models.ForeignKey(product,on_delete=models.CASCADE)
    user = models.ForeignKey(User,on_delete=models.CASCADE)
    order_quantity = models.IntegerField()
    order_total = models.IntegerField()
    order_shipped = models.BooleanField()


class address(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    house_name = models.CharField(max_length=255, blank=True)
    town = models.CharField(max_length=255, blank=True)
    post_office = models.CharField(max_length=255, blank=True)
    pincode = models.CharField(max_length=255)
    district = models.CharField(max_length=255, blank=True)
    land_mark = models.CharField(max_length=255, blank=True)
    phone = models.CharField(max_length=15, blank=True)

@receiver(post_save, sender=User)
    def create_user_address(sender, instance, created, **kwargs):
        if created:
            address.objects.create(user=instance)

@receiver(post_save, sender=User)
def save_user_address(sender, instance, **kwargs):
    instance.address.save()

Error message

PS C:\Users\sujit\OneDrive\Desktop\project\django> python manage.py makemigrations No changes detected PS C:\Users\sujit\OneDrive\Desktop\project\django> python manage.py migrate

Operations to perform: Apply all migrations: admin, auth, contenttypes, products, sessions Running migrations: Applying products.0004_auto_20211114_2342...Traceback (most recent call last): File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\backends\utils.py", line 84, in _execute return self.cursor.execute(sql, params) psycopg2.errors.SyntaxError: multiple default values specified for column "id" of table "products_customer"

The above exception was the direct cause of the following exception: Traceback (most recent call last): File "C:\Users\sujit\OneDrive\Desktop\project\django\manage.py", line 22, in main() File "C:\Users\sujit\OneDrive\Desktop\project\django\manage.py", line 18, in main execute_from_command_line(sys.argv) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management_init_.py", line 419, in execute_from_command_line utility.execute() File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management_init_.py", line 413, in execute self.fetch_command(subcommand).run_from_argv(self.argv) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\base.py", line 354, in run_from_argv self.execute(*args, **cmd_options) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\base.py", line 398, in execute output = self.handle(*args, **options) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\base.py", line 89, in wrapped res = handle_func(*args, **kwargs) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\commands\migrate.py", line 244, in handle post_migrate_state = executor.migrate( File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\executor.py", line 117, in migrate state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\executor.py", line 147, in _migrate_all_forwards state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\executor.py", line 227, in apply_migration state = migration.apply(state, schema_editor) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\migration.py", line 126, in apply operation.database_forwards(self.app_label, schema_editor, old_state, project_state) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\operations\fields.py", line 104, in database_forwards schema_editor.add_field( File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\backends\base\schema.py", line 522, in add_field self.execute(sql, params) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\backends\base\schema.py", line 145, in execute cursor.execute(sql, params) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\backends\utils.py", line 98, in execute return super().execute(sql, params) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\backends\utils.py", line 66, in execute return self._execute_with_wrappers(sql, params, many=False, executor=self._execute) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\backends\utils.py", line 75, in _execute_with_wrappers return executor(sql, params, many, context) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\backends\utils.py", line 84, in _execute return self.cursor.execute(sql, params) File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\utils.py", line 90, in exit raise dj_exc_value.with_traceback(traceback) from exc_value File "C:\Users\sujit\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\backends\utils.py", line 84, in _execute return self.cursor.execute(sql, params) django.db.utils.ProgrammingError: multiple default values specified for column "id" of table "products_customer"

Solution

I think you get this error because you try to make the migrations on a non-existent database table.

Try to delete everything from the migrations folder (except __init__.py), and delete the .sqlite3 database file as well, then rerun

python manage.py makemigrations

python manage.py migrate

Be aware, this will delete your database and your migrations so far!

But most likely it will fix your issue.

Answered By - ish