python - 无法弄清楚如何调试这个: ValueError: invalid literal for int() with base 10: '

Question

我刚刚遇到了这个错误，我尝试在论坛上类似错误的帮助下进行调试，但尚未解决任何问题。我想它来 self 的模型，涉及模型字段及其返回方式。特别是 Booking 和 Room 模型下的 Book_id 和 Room_Number 。任何帮助表示赞赏。注意:我更改了模型字段，每当我运行 manage.py migrate 时都会弹出值错误

模型.py

class Room(models.Model):
    Hostel = models.ForeignKey(List)
    Room_Number = models.CharField(max_length=3, default="", primary_key=True)
    Total_rooms = models.IntegerField(blank=True)
    Price_single = models.IntegerField(blank=True)
    Price_double = models.IntegerField(blank=True)

    def __str__(self):
        return self.Room_Number


class Booking(models.Model):
    Book_id = models.IntegerField(default="")
    Hostel = models.ForeignKey(List)
    Room_Number = models.ForeignKey(Room)
    Room_capacity = models.CharField(max_length=1, choices=[('S', 'Single'), ('D', 'Double')], default="")
    Booked_by = models.ForeignKey(Student, default="")
    Booked_on = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return "%s, booked a '%s' room in '%s' '%s' at '%s'" % (
            self.Booked_by, self.Room_capacity, self.Hostel, self.Room_Number, self.Booked_on)

在控制台中显示:

Running migrations:
  Rendering model states... DONE
  Applying Gyobera.0011_booking_book_id...Traceback (most recent call last):
  File "C:\Program Files (x86)\JetBrains\PyCharm 4.5.2\helpers\pycharm\django_manage.py", line 41, in <module>
    run_module(manage_file, None, '__main__', True)
  File "C:\Python34\lib\runpy.py", line 182, in run_module
    return _run_module_code(code, init_globals, run_name, mod_spec)
  File "C:\Python34\lib\runpy.py", line 96, in _run_module_code
    mod_name, mod_spec, pkg_name, script_name)
  File "C:\Python34\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:/Users/Scott Businge/Ewange\manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "C:\Python34\lib\site-packages\django\core\management\__init__.py", line 338, in execute_from_command_line
    utility.execute()
  File "C:\Python34\lib\site-packages\django\core\management\__init__.py", line 330, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "C:\Python34\lib\site-packages\django\core\management\base.py", line 390, in run_from_argv
    self.execute(*args, **cmd_options)
  File "C:\Python34\lib\site-packages\django\core\management\base.py", line 441, in execute
    output = self.handle(*args, **options)
  File "C:\Python34\lib\site-packages\django\core\management\commands\migrate.py", line 221, in handle
    executor.migrate(targets, plan, fake=fake, fake_initial=fake_initial)
  File "C:\Python34\lib\site-packages\django\db\migrations\executor.py", line 110, in migrate
    self.apply_migration(states[migration], migration, fake=fake, fake_initial=fake_initial)
  File "C:\Python34\lib\site-packages\django\db\migrations\executor.py", line 147, in apply_migration
    state = migration.apply(state, schema_editor)
  File "C:\Python34\lib\site-packages\django\db\migrations\migration.py", line 115, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "C:\Python34\lib\site-packages\django\db\migrations\operations\fields.py", line 62, in database_forwards
    field,
  File "C:\Python34\lib\site-packages\django\db\backends\sqlite3\schema.py", line 179, in add_field
    self._remake_table(model, create_fields=[field])
  File "C:\Python34\lib\site-packages\django\db\backends\sqlite3\schema.py", line 77, in _remake_table
    self.effective_default(field)
  File "C:\Python34\lib\site-packages\django\db\backends\base\schema.py", line 211, in effective_default
    default = field.get_db_prep_save(default, self.connection)
  File "C:\Python34\lib\site-packages\django\db\models\fields\__init__.py", line 710, in get_db_prep_save
    prepared=False)
  File "C:\Python34\lib\site-packages\django\db\models\fields\__init__.py", line 702, in get_db_prep_value
    value = self.get_prep_value(value)
  File "C:\Python34\lib\site-packages\django\db\models\fields\__init__.py", line 1868, in get_prep_value
    return int(value)
ValueError: invalid literal for int() with base 10: ''

Answer 1

您的 bookid 默认为空字符串，

Book_id = models.IntegerField(default="")

您可能想要允许空值或将默认值设置为数字

Book_id = models.IntegerField(default=1)