Django - Python 3 - "AssertionError: A model can't have more than one AutoField."

Question

I'm getting crazy over this.

I created my database with MySQLWorkbench

This his my Schema

Than I used the terminal command to get the model-code:

$python3 manage.py inspectdb

After passing the code to my models.py I try to use the models in the shell with

$python3 manage.py shell

But then I'm getting always this error:

"AssertionError: A model can't have more than one AutoField."

But the error makes no sense, since there are only one AutoField in each Model, see:

class Brands(models.Model):
    bid = models.AutoField(db_column='BID')  # Field name made lowercase.
    name = models.CharField(db_column='Name', max_length=45, blank=True, null=True)  # Field name made lowercase.
    fair = models.IntegerField(db_column='Fair', blank=True, null=True)  # Field name made lowercase.
    eco = models.IntegerField(db_column='Eco', blank=True, null=True)  # Field name made lowercase.
    country = models.CharField(db_column='Country', max_length=45, blank=True, null=True)  # Field name made lowercase.
    companies = models.ForeignKey('Companies', models.DO_NOTHING, db_column='Companies_ID')  # Field name made lowercase.

    class Meta:
        managed = False
        db_table = 'Brands'
        unique_together = (('bid', 'companies'),)


class Companies(models.Model):
    cid = models.AutoField(db_column='CID')  # Field name made lowercase.
    name = models.CharField(db_column='Name', max_length=45, blank=True, null=True)  # Field name made lowercase.
    fair = models.IntegerField(db_column='Fair', blank=True, null=True)  # Field name made lowercase.
    eco = models.IntegerField(db_column='Eco', blank=True, null=True)  # Field name made lowercase.
    country = models.CharField(db_column='Country', max_length=45, blank=True, null=True)  # Field name made lowercase.
    concerns = models.ForeignKey('Concerns', models.DO_NOTHING, db_column='Concerns_ID')  # Field name made lowercase.

    class Meta:
        managed = False
        db_table = 'Companies'
        unique_together = (('cid', 'concerns'),)


class Concerns(models.Model):
    cid = models.AutoField(db_column='CID', primary_key=True)  # Field name made lowercase.
    name = models.CharField(db_column='Name', max_length=45, blank=True, null=True)  # Field name made lowercase.
    fair = models.IntegerField(blank=True, null=True)
    eco = models.IntegerField(db_column='Eco', blank=True, null=True)  # Field name made lowercase.
    country = models.CharField(db_column='Country', max_length=45, blank=True, null=True)  # Field name made lowercase.

    class Meta:
        managed = False
        db_table = 'Concerns'


class Products(models.Model):
    pid = models.AutoField(db_column='PID')  # Field name made lowercase.
    name = models.CharField(db_column='Name', max_length=45, blank=True, null=True)  # Field name made lowercase.
    ean = models.IntegerField(db_column='EAN', blank=True, null=True)  # Field name made lowercase.
    fair = models.IntegerField(db_column='Fair', blank=True, null=True)  # Field name made lowercase.
    eco = models.IntegerField(db_column='Eco', blank=True, null=True)  # Field name made lowercase.
    companies_id = models.IntegerField(db_column='Companies_ID')  # Field name made lowercase.
    brands = models.ForeignKey(Brands, models.DO_NOTHING, db_column='Brands_ID')  # Field name made lowercase.
    brands_companies = models.ForeignKey(Brands, models.DO_NOTHING, db_column='Brands_Companies_ID')  # Field name made lowercase.

    class Meta:
        managed = False
        db_table = 'Products'
        unique_together = (('pid', 'companies_id', 'brands', 'brands_companies'),)


class ProductsHasShoppinglists(models.Model):
    products = models.ForeignKey(Products, models.DO_NOTHING, db_column='Products_ID')  # Field name made lowercase.
    products_companies = models.ForeignKey(Products, models.DO_NOTHING, db_column='Products_Companies_ID')  # Field name made lowercase.
    shoppinglists = models.ForeignKey('Shoppinglists', models.DO_NOTHING, db_column='ShoppingLists_ID')  # Field name made lowercase.
    shoppinglists_users = models.ForeignKey('Shoppinglists', models.DO_NOTHING, db_column='ShoppingLists_Users_ID')  # Field name made lowercase.

    class Meta:
        managed = False
        db_table = 'Products_has_ShoppingLists'
        unique_together = (('products', 'products_companies', 'shoppinglists', 'shoppinglists_users'),)


class Shoppinglists(models.Model):
    id = models.AutoField(db_column='ID')  # Field name made lowercase.
    products = models.CharField(db_column='Products', max_length=45, blank=True, null=True)  # Field name made lowercase.
    users = models.ForeignKey('Users', models.DO_NOTHING, db_column='Users_ID')  # Field name made lowercase.

    class Meta:
        managed = False
        db_table = 'ShoppingLists'
        unique_together = (('id', 'users'),)


class Users(models.Model):
    uid = models.AutoField(db_column='UID', primary_key=True)  # Field name made lowercase.
    firstname = models.CharField(db_column='FirstName', max_length=45, blank=True, null=True)  # Field name made lowercase.
    lastname = models.CharField(db_column='LastName', max_length=45, blank=True, null=True)  # Field name made lowercase.
    email = models.CharField(db_column='Email', max_length=45, blank=True, null=True)  # Field name made lowercase.

    class Meta:
        managed = False
        db_table = 'Users'

I just don't understand the problem!!!

Answer 1

From docs:

By default, Django gives each model the following field:

id = models.AutoField(primary_key=True)

This is an auto-incrementing primary key.

If you’d like to specify a custom primary key, just specify primary_key=True on one of your fields. If Django sees you’ve explicitly set Field.primary_key, it won’t add the automatic id column.

Each model requires exactly one field to have primary_key=True (either explicitly declared or automatically added).

So try to set primary_key=True like this:

bid = models.AutoField(db_column='BID', primary_key=True)

Answer 2

Try to set primary_key=True in yours AutoField's. Because if you dont set primary_key=True django will create Automatically other AutoFiled. See the doc bellow:

https://docs.djangoproject.com/en/1.11/ref/models/fields/ https://docs.djangoproject.com/en/1.11/topics/db/models/#automatic-primary-key-fields