python - Django 错误有时会发生

Question

我现在很迷茫。我在 Django 中运行一个脚本来创建一个假数据库，一遍又一遍地循环相同的代码。当出现以下错误时，我已经创建了超过 2.5k 个对象:

ProgrammingError: autocommit cannot be used inside a transaction

我查了一下，得到了一个显然已修复的错误单，但那是针对以前的版本，我使用的是 Django 1.6。这是完整的回溯:

---------------------------------------------------------------------------
ProgrammingError                          Traceback (most recent call last)
<ipython-input-31-0597bce30f92> in <module>()
----> 1 make_listeners()

<ipython-input-29-5697f122e144> in make_listeners()
     28                         seed = random.randint(0,len(user_ids_copy)-1)
     29                         requested_user = user_ids_copy.pop(seed)
---> 30                         user.functions.listen_to(requested_user)
     31                         print i, user.pk, number_seed, original_seed
     32                         number_seed -= 1

.../models.py in listen_to(self, user_id)
    715                 except User.DoesNotExist:
    716                         return 'User DoesNotExist'
--> 717                 request = ListenerRequest.objects.get_or_create(user=requesting, user_requested=requester, is_active=True)
    718                 if not request[1]:
    719                         if request.is_accepted:

/Library/Python/2.7/site-packages/Django-1.6-py2.7.egg/django/db/models/manager.pyc in get_or_create(self, **kwargs)
    152
    153     def get_or_create(self, **kwargs):
--> 154         return self.get_queryset().get_or_create(**kwargs)
    155
    156     def create(self, **kwargs):

/Library/Python/2.7/site-packages/Django-1.6-py2.7.egg/django/db/models/query.pyc in get_or_create(self, **kwargs)
    378                 obj = self.model(**params)
    379                 with transaction.atomic(using=self.db):
--> 380                     obj.save(force_insert=True, using=self.db)
    381                 return obj, True
    382             except DatabaseError:

/Library/Python/2.7/site-packages/Django-1.6-py2.7.egg/django/db/transaction.pyc in __exit__(self, exc_type, exc_value, traceback)
    328                     connection.autocommit = True
    329                 else:
--> 330                     connection.set_autocommit(True)
    331             # Outermost block exit when autocommit was disabled.
    332             elif not connection.savepoint_ids and not connection.commit_on_exit:

/Library/Python/2.7/site-packages/Django-1.6-py2.7.egg/django/db/backends/__init__.pyc in set_autocommit(self, autocommit)
    331         self.validate_no_atomic_block()
    332         self.ensure_connection()
--> 333         self._set_autocommit(autocommit)
    334         self.autocommit = autocommit
    335

/Library/Python/2.7/site-packages/Django-1.6-py2.7.egg/django/db/backends/postgresql_psycopg2/base.pyc in _set_autocommit(self, autocommit)
    171     def _set_autocommit(self, autocommit):
    172         if self.psycopg2_version >= (2, 4, 2):
--> 173             self.connection.autocommit = autocommit
    174         else:
    175             if autocommit:

ProgrammingError: autocommit cannot be used inside a transaction

如果前 2500 个对象没有这个问题，为什么我会收到这个错误？

型号:

根据要求，这是 ListenerRequest 的模型，因为它似乎是导致错误的原因:

class ListenerRequest(models.Model):
    listener_relationship_id = models.AutoField(primary_key=True)
    #user is the person asking to listen
    user = models.ForeignKey(User, related_name='requests')
    #user_requested is the person being asked to be listen to
    user_requested = models.ForeignKey(User, related_name='requested')
    date_requested = models.DateTimeField(auto_now_add=True)
    date_accepted = models.DateTimeField(null=True,blank=True)
    denied_flag = models.BooleanField(default=False)
    denied_date = models.DateTimeField(null=True,blank=True)
    unlistened_flag = models.BooleanField(default=False)
    unlistened_date = models.DateTimeField(null=True,blank=True)
    is_active = models.BooleanField(default=True)
    is_accepted = models.BooleanField(default=False)

Answer 1

如果您使用的是 django_postgrespool，当前版本(在撰写本文时)正在吞噬错误并返回一般错误“ProgrammingError:autocommit cannot be used inside a transaction”。

您可以通过暂时注释掉 settings.py 中的以下行来查看实际错误

DATABASES['default']['ENGINE'] = 'django_postgrespool'

有关更多详细信息，请参阅当前 Unresolved 问题:https://github.com/kennethreitz/django-postgrespool/issues/24