Python 德扬戈元'；不要运行迁移。TypeError:应为字符串或缓冲区

当我尝试在Django项目中运行迁移时，我得到了

TypeError：预期的字符串或缓冲区。如果我将
日期字段添加到现有模型
creation=models.DateField（auto\u now\u add=True）
，则会发生这种情况

我能绕过它的唯一方法是启动一个新项目，将代码从旧复制到新。我尝试过删除迁移，删除数据库，删除最初导致问题的代码

如何在删除所有错误后仍然会弹出错误？更重要的是，如何在实时数据库上阻止错误发生

回溯

Applying apps.0011_auto_20150928_1515...Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/core/management/__init__.py", line 338, in execute_from_command_line
    utility.execute()
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/core/management/__init__.py", line 330, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/core/management/base.py", line 393, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/core/management/base.py", line 444, in execute
    output = self.handle(*args, **options)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 222, in handle
    executor.migrate(targets, plan, fake=fake, fake_initial=fake_initial)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/migrations/executor.py", line 110, in migrate
    self.apply_migration(states[migration], migration, fake=fake, fake_initial=fake_initial)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/migrations/executor.py", line 148, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/migrations/migration.py", line 115, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/migrations/operations/fields.py", line 62, in database_forwards
    field,
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/backends/sqlite3/schema.py", line 179, in add_field
    self._remake_table(model, create_fields=[field])
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/backends/sqlite3/schema.py", line 77, in _remake_table
    self.effective_default(field)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/backends/base/schema.py", line 211, in effective_default
    default = field.get_db_prep_save(default, self.connection)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/models/fields/__init__.py", line 710, in get_db_prep_save
    prepared=False)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/models/fields/__init__.py", line 1322, in get_db_prep_value
    value = self.get_prep_value(value)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/models/fields/__init__.py", line 1317, in get_prep_value
    return self.to_python(value)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/models/fields/__init__.py", line 1274, in to_python
    parsed = parse_date(value)
  File "/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/utils/dateparse.py", line 60, in parse_date
    match = date_re.match(value)
TypeError: expected string or buffer

应用apps.0011\u auto\u 20150928\u 1515…回溯（最近一次呼叫最后一次）：
文件“manage.py”，第10行，在
从命令行（sys.argv）执行命令
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/core/management/__init__uuuuuu.py”，第338行，从命令行执行
utility.execute（）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/core/management/_-init___.py”，第330行，在execute中
self.fetch_命令（子命令）。从_argv（self.argv）运行_
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/core/management/base.py”，第393行，运行时从
self.execute（*args，**cmd_选项）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/core/management/base.py”，执行中第444行
输出=self.handle（*args，**选项）
handle中的文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/core/management/commands/migrate.py”，第222行
executor.migrate（目标、计划、假=假、假首字母=假首字母）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/migrations/executor.py”，第110行，在migrate中
self.apply\u迁移（状态[迁移]，迁移，假=假，假首字母=假首字母）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/migrations/executor.py”，第148行，在apply_migration中
state=migration.apply（状态，模式编辑器）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/migrations/migration.py”，第115行，在apply中
操作。数据库转发（self.app\u标签、模式编辑器、旧状态、项目状态）
数据库中的文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/migrations/operations/fields.py”，第62行
领域
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/backends/sqlite3/schema.py”，第179行，在add_字段中
self.\u重新生成\u表（模型，创建字段=[field]）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/backends/sqlite3/schema.py”，第77行，在“重新制作”表中
自生效默认值（字段）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/backends/base/schema.py”，第211行，默认有效
默认值=field.get\u db\u prep\u save（默认值，self.connection）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/models/fields/_init__.py”，第710行，在get_db_prep_save中
准备就绪（错误）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/models/fields/__init____;.py”，第1322行，在get_db_prep_值中
value=self.get\u prep\u值（value）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/db/models/fields/__init____;.py”，第1317行，在get_prep_值中
返回self.to_python（值）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site-packages/django/db/models/fields/_-init___;.py”，第1274行，在python中
已解析=解析日期（值）
文件“/Users/Name/pyProjects/projects/project/env/lib/python2.7/site packages/django/utils/dateparse.py”，parse_date中的第60行
匹配=日期匹配（值）
TypeError:应为字符串或缓冲区
请显示完整的错误和回溯。我已经添加了感谢您也可以发布您的模型！？你能不能也写一下Django的版本和你使用的数据库？我的模型里有什么并不重要。我可以注释掉所有的代码，但我仍然能够理解。请显示完整的错误并进行回溯。我已经添加了感谢您也可以发布您的模型！？你能不能也写一下Django的版本和你使用的数据库？我的模型里有什么并不重要。我可以注释掉所有代码，但我仍然能理解。