Another Cannot set values on a ManyToManyField which specifies an intermediary model
我得到错误：
我被ipaswdb.providerlocations manager部分绊倒了，我在views.py中的代码中认为，我以有效的形式正确地处理了模型的M2M关系。
我确实看到了这个答案：Django无法在指定中间模型的ManyToManyField上设置值。改用管理器
这导致我添加了self.object.save()，但似乎没有做任何事情。在updateView中，代码似乎可以工作，但我要检查，即使我选择了两个位置，通过print语句，我可以看到从表单返回，我在数据库中只看到一个…
我确实在createView上看到了这个错误，添加了self.object.save()或不添加self.object.save()(我以为我得到它是因为commit=false，而该对象尚未保存)。我也会在底部添加涉及的模型，它们的关系很复杂。
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 | class ProviderCreateView(CreateView): model = Provider form_class = ProviderForm template_name = 'ipaswdb/provider/provider_form.html' success_url = 'ipaswdb/provider/' def form_valid(self, form): self.object = form.save(commit=True) #traceback shows this as offending line ProviderLocations.objects.filter(provider=self.object).delete() self.object.save() for group_location in form.cleaned_data['group_locations']: location = ProviderLocations() location.provider = self.object location.group_location = group_location location.save() return super(ModelFormMixin, self).form_valid(form) class ProviderUpdateView(UpdateView): model = Provider form_class = ProviderForm template_name = 'ipaswdb/provider/provider_form.html' success_url = 'ipaswdb/provider/' def form_valid(self, form): self.object = form.save(commit=False) ProviderLocations.objects.filter(provider=self.object).delete() self.object.save() for group_location in form.cleaned_data['group_locations']: print("here!" + self.object.first_name) location = ProviderLocations() location.provider = self.object location.group_location = group_location location.save() return super(ModelFormMixin, self).form_valid(form) |
然后我的模型：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 | class Provider(models.Model): first_name = models.CharField(max_length = 50) last_name = models.CharField(max_length = 50) date_of_birth = models.DateField(auto_now_add=False) group_locations = models.ManyToManyField('GroupLocations', through='ProviderLocations', blank=True, null=True) etc... class ProviderLocations(models.Model): #group_location = models.ForeignKey('GroupLocations', on_delete=models.CASCADE) provider = models.ForeignKey('Provider', on_delete=models.CASCADE) group_location = models.ForeignKey('GroupLocations', on_delete=models.CASCADE) created_at=models.DateField(auto_now_add=True) updated_at=models.DateField(auto_now=True) def __str__(self): return self.provider.first_name class GroupLocations(models.Model): address = models.ForeignKey('Address', on_delete= models.SET_NULL, null=True) group = models.ForeignKey('Group', on_delete=models.CASCADE) doing_business_as = models.CharField(max_length = 255) created_at=models.DateField(auto_now_add=True) updated_at=models.DateField(auto_now=True) def __str__(self): return self.doing_business_as class Group(models.Model): group_name = models.CharField(max_length=50) etc... |
好的，调试日志一直向上显示这个SQL在打印语句显示它试图添加的许多位置时只执行一次插入：
1 2 3 4 5 6 7 8 9 10 | 0.001) SELECT"ipaswdb_grouplocations"."id","ipaswdb_grouplocations"."address_id","ipaswdb_grouplocations"."group_id","ipaswdb_grouplocations"."doing_business_as","ipaswdb_grouplocations"."created_at","ipaswdb_grouplocations"."updated_at" FROM"ipaswdb_grouplocations" WHERE"ipaswdb_grouplocations"."id" IN (3, 2, 5, 4); args=(3, 2, 5, 4) (0.000) BEGIN; args=None (0.000) DELETE FROM"ipaswdb_providerlocations" WHERE"ipaswdb_providerlocations"."provider_id" = NULL; args=(None,) (0.000) BEGIN; args=None (0.001) INSERT INTO"ipaswdb_provider" ("first_name","last_name","date_of_birth","license_number","license_experation","dea_number","dea_experation","phone","fax","ptan","caqh_number","effective_date","provider_npi","provisional_effective_date","date_joined","provider_contact","credentialing_contact","notes","hospital_affiliation","designation_id","specialty_id","created_at","updated_at") VALUES ('Onemore', 'Test', '2016-08-12', 'kljlk', '2016-08-12', 'kljjkl', '2016-08-12', '', '', '', 'lk;fsd', '2016-08-12', 'jksalfas', '2016-08-12', '2016-08-12', 'kj;jasdf', ';kjsfas', '', '', NULL, NULL, '2016-08-12', '2016-08-12'); args=[u'Onemore', u'Test', u'2016-08-12', u'kljlk', u'2016-08-12', u'kljjkl', u'2016-08-12', u'', u'', u'', u'lk;fsd', u'2016-08-12', u'jksalfas', u'2016-08-12', u'2016-08-12', u'kj;jasdf', u';kjsfas', u'', u'', None, None, u'2016-08-12', u'2016-08-12'] here!IPAABQ <-- all the locations to add is with the here! here!ststs here!2312 here!fsfd315 (0.000) BEGIN; args=None |
见一个插入
1 2 3 4 5 | (0.000) INSERT INTO"ipaswdb_providerlocations" ("provider_id","group_location_id","created_at","updated_at") VALUES (22, 5, '2016-08-12', '2016-08-12'); args=[22, 5, u'2016-08-12', u'2016-08-12'] [12/Aug/2016 19:46:26]"POST /ipaswdb/provider/add/ HTTP/1.1" 302 0 (0.001) SELECT COUNT(*) AS"__count" FROM"ipaswdb_provider"; args=() (0.000) SELECT"ipaswdb_provider"."id","ipaswdb_provider"."first_name","ipaswdb_provider"."last_name","ipaswdb_provider"."date_of_birth","ipaswdb_provider"."license_number","ipaswdb_provider"."license_experation","ipaswdb_provider"."dea_number","ipaswdb_provider"."dea_experation","ipaswdb_provider"."phone","ipaswdb_provider"."fax","ipaswdb_provider"."ptan","ipaswdb_provider"."caqh_number","ipaswdb_provider"."effective_date","ipaswdb_provider"."provider_npi","ipaswdb_provider"."provisional_effective_date","ipaswdb_provider"."date_joined","ipaswdb_provider"."provider_contact","ipaswdb_provider"."credentialing_contact","ipaswdb_provider"."notes","ipaswdb_provider"."hospital_affiliation","ipaswdb_provider"."designation_id","ipaswdb_provider"."specialty_id","ipaswdb_provider"."created_at","ipaswdb_provider"."updated_at" FROM"ipaswdb_provider" LIMIT 3; args=() [12/Aug/2016 19:46:26]"GET /ipaswdb/provider/add/ipaswdb/provider/ HTTP/1.1" 200 4835 |
看起来有点像Traceback：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 | Environment: Request Method: POST Request URL: http://localhost:8001/ipaswdb/provider/add/ Django Version: 1.9.5 Python Version: 2.7.11 Installed Applications: ['ipaswdb.apps.IpaswdbConfig', 'django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.messages', 'django.contrib.staticfiles'] Installed Middleware: ['django.middleware.security.SecurityMiddleware', 'django.contrib.sessions.middleware.SessionMiddleware', 'django.middleware.common.CommonMiddleware', 'django.middleware.csrf.CsrfViewMiddleware', 'django.contrib.auth.middleware.AuthenticationMiddleware', 'django.contrib.auth.middleware.SessionAuthenticationMiddleware', 'django.contrib.messages.middleware.MessageMiddleware', 'django.middleware.clickjacking.XFrameOptionsMiddleware'] Traceback: File"/usr/local/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response 149. response = self.process_exception_by_middleware(e, request) File"/usr/local/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response 147. response = wrapped_callback(request, *callback_args, **callback_kwargs) File"/usr/local/lib/python2.7/site-packages/django/views/generic/base.py" in view 68. return self.dispatch(request, *args, **kwargs) File"/usr/local/lib/python2.7/site-packages/django/views/generic/base.py" in dispatch 88. return handler(request, *args, **kwargs) File"/usr/local/lib/python2.7/site-packages/django/views/generic/edit.py" in post 256. return super(BaseCreateView, self).post(request, *args, **kwargs) File"/usr/local/lib/python2.7/site-packages/django/views/generic/edit.py" in post 222. return self.form_valid(form) File"/Users/shane.thomas/programming/py3env/ipa_django/mysite/ipaswdb/views.py" in form_valid 38. self.object = form.save(commit=True) File"/usr/local/lib/python2.7/site-packages/django/forms/models.py" in save 452. self._save_m2m() File"/usr/local/lib/python2.7/site-packages/django/forms/models.py" in _save_m2m 434. f.save_form_data(self.instance, cleaned_data[f.name]) File"/usr/local/lib/python2.7/site-packages/django/db/models/fields/related.py" in save_form_data 1618. setattr(instance, self.attname, data) File"/usr/local/lib/python2.7/site-packages/django/db/models/fields/related_descriptors.py" in __set__ 481. manager.set(value) File"/usr/local/lib/python2.7/site-packages/django/db/models/fields/related_descriptors.py" in set 882. (opts.app_label, opts.object_name) Exception Type: AttributeError at /ipaswdb/provider/add/ Exception Value: Cannot set values on a ManyToManyField which specifies an intermediary model. Use ipaswdb.ProviderLocations's Manager instead. |
保存保存时不要提交。如本文所述，如果指定
通过指定