在django中进行迁移错误：“没有这样的表”

Question

当我试图进行迁移时: python manage.py

发生以下错误: django.db.utils.OperationalError:没有这样的表: blog_category

Traceback (most recent call last):
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\utils.py", line 84, in _execute
return self.cursor.execute(sql, params)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django \db\backends\sqlite3\base.py", line 383, in execute
return Database.Cursor.execute(self, query, params)
sqlite3.OperationalError: no such table: blog_category

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
File "manage.py", line 15, in <module>
execute_from_command_line(sys.argv)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django \core\management\__init__.py", line 381, in execute_from_command_line
utility.execute()
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\management\__init__.py", line 375, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\management\base.py", line 323, in run_from_argv
self.execute(*args, **cmd_options)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\management\base.py", line 361, in execute
self.check()
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\management\base.py", line 390, in check
include_deployment_checks=include_deployment_checks,
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\management\base.py", line 377, in _run_checks
return checks.run_checks(**kwargs)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\checks\registry.py", line 72, in run_checks
new_errors = check(app_configs=app_configs)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\checks\urls.py", line 40, in check_url_namespaces_unique
all_namespaces = _load_all_namespaces(resolver)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\checks\urls.py", line 57, in _load_all_namespaces
url_patterns = getattr(resolver, 'url_patterns', [])
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\utils\functional.py", line 80, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\urls\resolvers.py", line 571, in url_patterns
patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\utils\functional.py", line 80, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\urls\resolvers.py", line 564, in urlconf_module
return import_module(self.urlconf_name)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\importlib\__init__.py",   line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
File "<frozen importlib._bootstrap>", line 983, in _find_and_load
File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 728, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "C:\xampp\htdocs\Django project\blooper\Bona-Blog-master\bona_blog\urls.py", line 27, in <module>
path('', include('blog.urls', namespace='blog')),  # Urls for article app.
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\urls\conf.py", line 34, in include
urlconf_module = import_module(urlconf_module)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\importlib\__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
File "<frozen importlib._bootstrap>", line 983, in _find_and_load
File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 728, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "C:\xampp\htdocs\Django project\blooper\Bona-Blog-master\blog\urls.py", line 5, in <module>
from blog.views.blog.article_views import (
File "C:\xampp\htdocs\Django project\blooper\Bona-Blog-master\blog\views\blog\article_views.py", line 25, in <module>
from blog.forms.blog.article_forms import (
File "C:\xampp\htdocs\Django project\blooper\Bona-Blog-master\blog\forms\blog\article_forms.py", line 16, in <module>
class ArticleCreateForm(forms.ModelForm):
File "C:\xampp\htdocs\Django project\blooper\Bona-Blog-master\blog\forms\blog\article_forms.py", line 18, in ArticleCreateForm
class Meta:
File "C:\xampp\htdocs\Django project\blooper\Bona-Blog-master\blog\forms\blog\article_forms.py", line 47, in Meta
"data-live-search": "true"
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\forms\widgets.py", line 562, in __init__
self.choices = list(choices)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\models\query.py", line 274, in __iter__
self._fetch_all()
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\models\query.py", line 1242, in _fetch_all
self._result_cache = list(self._iterable_class(self))
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\models\query.py", line 55, in __iter__
results = compiler.execute_sql(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\models\sql\compiler.py", line 1097, in execute_sql
cursor.execute(sql, params)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\utils.py", line 99, in execute
return super().execute(sql, params)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\utils.py", line 67, in execute
return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\utils.py", line 76, in _execute_with_wrappers
return executor(sql, params, many, context)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\utils.py", line 84, in _execute
return self.cursor.execute(sql, params)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\utils.py", line 89, in __exit__
raise dj_exc_value.with_traceback(traceback) from exc_value
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\utils.py", line 84, in _execute
return self.cursor.execute(sql, params)
File "C:\Users\injemam\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\db\backends\sqlite3\base.py", line 383, in execute
return Database.Cursor.execute(self, query, params)
django.db.utils.OperationalError: no such table: blog_category

使用Django-2.2

Answer 1

显然，

1. 或者手动更改了db表(例如通过db接口)
2. 您丢失了一个或多个所需的迁移文件。

由于您所处的是一个开发环境，我建议您

• 删除分贝
• 重新创建数据库
• 然后又是python manage.py migrate

Answer 2

这是博客软件中的一个漏洞。

在创建迁移时，代码中的模型将被内省，在此过程中，许多模块将与模型一起导入。在软件中，有一点是在导入时进行查询的(article_forms.py，第40行 )。此时，查询指向的表还不存在，并且失败了。

可能作者没有注意到错误，因为他/她在进行更改时已经拥有了表。他/她从来没有从头开始创建一个新的实例。

你应该把它报告为窃听器。

Answer 3

由于您正处于开发阶段，您可以放弃数据库并重新创建它。但在重新创建之前，删除所有应用程序上的所有以前的迁移文件。确保那些文件夹中只有lnlt文件。