在Django中批量删除项目时引发AttributeError异常

Question

我正在尝试在我的Django网站的开发环境中批量删除所有评论，但Django却抛出了一个AttributeException的错误。

我在Python命令行中运行了以下代码：

>>> from django.contrib.comments.models import Comment
>>> Comment.objects.all().delete()
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/home/jeff/.virtualenvs/osl_main-website/lib/python2.6/site-packages/django/db/models/query.py", line 441, in delete
    obj._collect_sub_objects(seen_objs)
  File "/home/jeff/.virtualenvs/osl_main-website/lib/python2.6/site-packages/django/db/models/base.py", line 569, in _collect_sub_objects
    sub_obj._collect_sub_objects(seen_objs, self, related.field.null)
  File "/home/jeff/.virtualenvs/osl_main-website/lib/python2.6/site-packages/django/db/models/base.py", line 585, in _collect_sub_objects
    delete_qs = rel_descriptor.delete_manager(self).all()
AttributeError: 'ReverseSingleRelatedObjectDescriptor' object has no attribute 'delete_manager'

我不太明白为什么删除的操作没有成功。有没有人能帮我看看这是为什么，以及我该如何解决这个问题？

关于我的模型的额外信息：

我有一个叫做OslComment的模型，它是从Comment模型继承而来的。我还有一个Vote模型，它指向OslComment中的条目。

BaseCommentAbstractModel

class BaseCommentAbstractModel(models.Model):
    """
    An abstract base class that any custom comment models probably should
    subclass.
    """

    # Content-object field
    content_type   = models.ForeignKey(ContentType,
            verbose_name=_('content type'),
            related_name="content_type_set_for_%(class)s")
    object_pk      = models.TextField(_('object ID'))
    content_object = generic.GenericForeignKey(ct_field="content_type", fk_field="object_pk")

    # Metadata about the comment
    site        = models.ForeignKey(Site)

Comment

class Comment(BaseCommentAbstractModel):
    """
    A user comment about some object.
    """

    # Who posted this comment? If ``user`` is set then it was an authenticated
    # user; otherwise at least user_name should have been set and the comment
    # was posted by a non-authenticated user.
    user        = models.ForeignKey(User, verbose_name=_('user'),
                    blank=True, null=True, related_name="%(class)s_comments")
    user_name   = models.CharField(_("user's name"), max_length=50, blank=True)
    user_email  = models.EmailField(_("user's email address"), blank=True)
    user_url    = models.URLField(_("user's URL"), blank=True)

    comment = models.TextField(_('comment'), max_length=COMMENT_MAX_LENGTH)

    # Metadata about the comment
    submit_date = models.DateTimeField(_('date/time submitted'), default=None)
    ip_address  = models.IPAddressField(_('IP address'), blank=True, null=True)
    is_public   = models.BooleanField(_('is public'), default=True,
                    help_text=_('Uncheck this box to make the comment effectively ' \
                                'disappear from the site.'))
    is_removed  = models.BooleanField(_('is removed'), default=False,
                    help_text=_('Check this box if the comment is inappropriate. ' \
                                'A "This comment has been removed" message will ' \
                                'be displayed instead.'))

OslComment

class OslComment(Comment):
    parent_comment = models.ForeignKey(Comment, blank=True, null=True, related_name='parent_comment')
    inline_to_object = models.BooleanField(default=False)
    edit_timestamp = models.DateTimeField()
    transformed_comment = models.TextField(editable=False)
    is_deleted_by_user = models.BooleanField(default=False)

Vote

class Vote(models.Model):
    """
    A vote on an object by a User.
    """
    user         = models.ForeignKey(User)
    content_type = models.ForeignKey(ContentType)
    object_id    = models.PositiveIntegerField()
    object       = generic.GenericForeignKey('content_type', 'object_id')
    vote         = models.SmallIntegerField(choices=SCORES)

其他信息：

Python版本：2.6.5
操作系统：Linux Mint 9 (Linux 2.6.32-21-generic)
Django版本：1.2
数据库驱动：postgresql_psycopg2 (2.2.1)

django postgresql model inheritance attributeerror exception handling linux mint bulk delete comment model

在Django中批量删除项目时引发AttributeError异常

1 个回答

撰写回答