Django migrate value invalid literal

Question

I have problem with Django migrate function. I was trying to add new field to my user model and it looks like this.

class UserProfile(models.Model):
    """ Model to represent additional information about user """
    user = models.OneToOneField(
        User,
        on_delete=models.CASCADE,
        related_name='profile'
    )
    bio = models.TextField(
        max_length=2000,
        blank=True,
        default=''
    )
    # we use URL instead of imagefield because we'll use 3rd party img hosting later on
    avatar = models.URLField(default='', blank=True)
    status = models.CharField(max_length=16, default='', blank=True)
    name = models.CharField(max_length=32, default='')
    balance = models.BigIntegerField(default='0')

    def __str__(self):
        return self.user.username

balance is new what I added, and after that I'm receving messages like

Operations to perform: Apply all migrations: accounts, admin, auth, authtoken, contenttypes, forums, posts, sessions, threads Running migrations: Applying accounts.0005_userprofile_balance...Traceback (most recent call last): File "manage.py", line 15, in execute_from_command_line(sys.argv) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\core\management__init__.py", line 371, in execute_from_command_line utility.execute() File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\core\management__init__.py", line 365, in execute self.fetch_command(subcommand).run_from_argv(self.argv) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\core\management\base.py", line 288, in run_from_argv self.execute(*args, **cmd_options) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\core\management\base.py", line 335, in execute output = self.handle(*args, **options) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\core\management\commands\migrate.py", line 200, in handle fake_initial=fake_initial, File "C:\Users\Rade\Desktop\rengorum-master\backend\env\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\Rade\Desktop\rengorum-master\backend\env\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\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\db\migrations\executor.py", line 244, in apply_migration state = migration.apply(state, schema_editor) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\db\migrations\migration.py", line 122, in apply operation.database_forwards(self.app_label, schema_editor, old_state, project_state) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\db\migrations\operations\fields.py", line 84, in database_forwards field, File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\db\backends\sqlite3\schema.py", line 315, in add_field self._remake_table(model, create_field=field) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\db\backends\sqlite3\schema.py", line 187, in _remake_table self.effective_default(create_field) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\db\backends\base\schema.py", line 240, in effective_default default = field.get_db_prep_save(default, self.connection) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\db\models\fields__init__.py", line 767, in get_db_prep_save return self.get_db_prep_value(value, connection=connection, prepared=False) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\db\models\fields__init__.py", line 762, in get_db_prep_value value = self.get_prep_value(value) File "C:\Users\Rade\Desktop\rengorum-master\backend\env\lib\site-packages\django\db\models\fields__init__.py", line 1826, in get_prep_value return int(value) ValueError: invalid literal for int() with base 10: ''

after I received that message, I tried to set default value to 0.00, but it's still same message, I deleted balance field and still receiving same message. Any ideas?

Answer 1

This is basically a migration issue, as the migration files are generated based on your initial codes and when migrating, these migration files are being executed and throwing errors.

I think you can use either one of the following solution to fix it:

Solution One

First you should delete the migration file(ie 0003_auto_<some id>.py) inside <app>/migrations directory which was created when you ran python manage.py makemigrations. If you are unsure about which one to delete, then check the django_migrations table in your database and see till which migrations it has been applied. After removing the last migration file(or files), you need to change the default value to 0. Then you should run makemigrations and migrate commands.

Solution Two

Change the default value to 0 in models. Then change the migration file which has been created when you added the Field in model, like this:

    operations = [
        migrations.AddField(
            model_name='userprofile',
            name='balance',
            field=models.BigIntegerField(default=0),  # instead of default='0'
        ),

Also you should remove the additional migration files(if they are generated) when you fixed the default value and re ran the migration commands.

Answer 2

BigIntegerField default value needs to be a whole number and not in quotes:

balance = models.BigIntegerField(default=0)

alternatively, if you need decimals:

balance = models.DecimalField(max_digits=6, decimal_places=2, default=0)

or use MoneyField https://github.com/django-money/django-money