嘿，我正在尝试初始化一个新数据库，但在设置迁移时遇到了一些问题。我得到的错误似乎源于设置我的表格。在我使用的表单中，我正在创建一个选择字段:
from django import forms
from ..custom_admin import widgets, choices
class MemberForm(forms.Form):
provinces = forms.ChoiceField(label='Provinces', choices=choices.PROVINCE_CHOICES, required=True)
PROVINCE_CHOICES 来自这里:
from ..base.models import ProvinceCode
PROVINCE_CHOICES = []
for province in ProvinceCode.objects.filter(country_code_id=1).order_by('code'):
PROVINCE_CHOICES.append((province.code, province.code))
问题似乎是在迁移发生之前调用了这个循环，给我一个错误，指出 Province 模型不存在。注释掉对该文件的引用允许迁移工作，但是，这似乎是继续使用的不切实际的解决方案。有办法解决这个错误吗？
作为引用，这是我在运行 manage.py makemigrations 时遇到的错误:
./manage.py makemigrations
Traceback (most recent call last):
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/db/backends/utils.py", line 64, in execute
return self.cursor.execute(sql, params)
psycopg2.ProgrammingError: relation "pc_psr_code" does not exist
LINE 1: ...escription", "pc_psr_code"."country_code_id" FROM "pc_psr_co...
^
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "./manage.py", line 9, in <module>
django.setup()
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/__init__.py", line 18, in setup
apps.populate(settings.INSTALLED_APPS)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/apps/registry.py", line 115, in populate
app_config.ready()
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/debug_toolbar/apps.py", line 15, in ready
dt_settings.patch_all()
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/debug_toolbar/settings.py", line 228, in patch_all
patch_root_urlconf()
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/debug_toolbar/settings.py", line 216, in patch_root_urlconf
reverse('djdt:render_panel')
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/core/urlresolvers.py", line 568, in reverse
app_list = resolver.app_dict[ns]
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/core/urlresolvers.py", line 360, in app_dict
self._populate()
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/core/urlresolvers.py", line 293, in _populate
for pattern in reversed(self.url_patterns):
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/utils/functional.py", line 33, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/core/urlresolvers.py", line 417, in url_patterns
patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/utils/functional.py", line 33, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/core/urlresolvers.py", line 410, in urlconf_module
return import_module(self.urlconf_name)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/importlib/__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 986, in _gcd_import
File "<frozen importlib._bootstrap>", line 969, in _find_and_load
File "<frozen importlib._bootstrap>", line 958, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 673, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 662, in exec_module
File "<frozen importlib._bootstrap>", line 222, in _call_with_frames_removed
File "/Users/js/Documents/app/platform/test/pc/urls.py", line 7, in <module>
from .custom_admin import urls as custom_urls
File "/Users/js/Documents/app/platform/test/pc/custom_admin/urls.py", line 3, in <module>
from ..party import views as party_views
File "/Users/js/Documents/app/platform/test/pc/party/views.py", line 1, in <module>
from ..party import forms
File "/Users/js/Documents/app/platform/test/pc/party/forms.py", line 2, in <module>
from ..custom_admin import widgets, choices
File "/Users/js/Documents/app/platform/test/pc/custom_admin/choices.py", line 9, in <module>
for province in ProvinceCode.objects.filter(country_code_id=1).order_by('code'):
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/db/models/query.py", line 258, in __iter__
self._fetch_all()
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/db/models/query.py", line 1074, in _fetch_all
self._result_cache = list(self.iterator())
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/db/models/query.py", line 52, in __iter__
results = compiler.execute_sql()
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/db/models/sql/compiler.py", line 848, in execute_sql
cursor.execute(sql, params)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/db/backends/utils.py", line 79, in execute
return super(CursorDebugWrapper, self).execute(sql, params)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/db/backends/utils.py", line 64, in execute
return self.cursor.execute(sql, params)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/db/utils.py", line 95, in __exit__
six.reraise(dj_exc_type, dj_exc_value, traceback)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/utils/six.py", line 685, in reraise
raise value.with_traceback(tb)
File "/Users/js/Documents/VirtualEnvironments/pcenv/lib/python3.5/site-packages/django/db/backends/utils.py", line 64, in execute
return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: relation "pc_psr_code" does not exist
LINE 1: ...escription", "pc_psr_code"."country_code_id" FROM "pc_psr_co...
省模型:
class ProvinceCode(models.Model):
code = models.CharField(blank=False, null=False, unique=True)
country_code = models.ForeignKey('CountryCode', blank=False, null=True)
请您参考如下方法:
您不能在应用注册表初始化期间执行查询。您的 choices.py 文件在此期间被间接导入，导致错误。要解决此问题，您可以将可调用传递给 choices:
def get_provinces():
province_choices = []
for province in ProvinceCode.objects.filter(country_code_id=1).order_by('code'):
province_choices.append((province.code, province.code))
return province_choices
class MemberForm(forms.Form):
provinces = forms.ChoiceField(label='Provinces', choices=get_provinces, required=True)
