Django Query Json Result

Question

在我的代码中，我创建了这个'dict'类型数组：

blog_reference = {'reference': kwargs.get('reference')}

它被保存到数据库表列中content_reference：

class UsageStatistics(models.Model):
    content_type_choices = (
        ('unspecified', 'Unspecified'),
        ('blog', 'Blog'),
        ('newsletter', 'Newsletter'),
        ('video', 'Video'),
    )
    reference = models.BigAutoField(primary_key=True)
    access_date = models.DateTimeField(blank=True, null=True)
    ip_address = models.GenericIPAddressField()
    passport_user = models.ForeignKey('Passport', models.DO_NOTHING, blank=True, null=True)
    language_iso = models.TextField()
    content_type = models.CharField(
        max_length=12,
        choices=content_type_choices,
        default='unspecified'
    )
    content_reference = JSONField()
    class Meta:
        db_table = 'usage_statistics'

我编写了以下数据库查询：

result = UsageStatistics.objects.filter(
    content_type='blog',access_date__gte=datetime.utcnow() - timedelta(days=90)
).values('content_reference').annotate(
    total=Count('reference')
).order_by('-total')[:10]

它给出的结果是：

<QuerySet [
    {'total': 1, 'content_reference': {'reference': '160'}}, 
    {'total': 1, 'content_reference': {'reference': '159'}}, 
    {'total': 1, 'content_reference': {'reference': '162'}}
]>

通过这个 FOR 循环，我尝试访问 content_reference['reference'] 的所有值(即 160、159、162(并将它们放入数组in_array。

for item in result:
    content_reference = json.loads(item['content_reference'])
    in_array.append(content_reference.reference)

这是错误的完整回溯content_reference = json.loads(item.content_reference( 正在创建：

追踪：

File "/usr/local/lib/python3.5/dist-packages/django/core/handlers/exception.py" in inner
  42.             response = get_response(request)
File "/usr/local/lib/python3.5/dist-packages/django/core/handlers/base.py" in _get_response
  187.                 response = self.process_exception_by_middleware(e, request)
File "/usr/local/lib/python3.5/dist-packages/django/core/handlers/base.py" in _get_response
  185.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/rpiggott/PyCharmProjects/rons-home.net/blog/views.py" in popular
  253.     result = ServicePopular.search()
File "/home/rpiggott/PyCharmProjects/rons-home.net/blog/service/popular.py" in search
  34.             b = json.loads(item.content_reference)
Exception Type: AttributeError at /en/blog/popular
Exception Value: 'dict' object has no attribute 'content_reference'

Answer 1

你可以做

for item in result:
    content_reference = item['content_reference']
    in_array.append(content_reference['reference'])

Answer 2

如果你只想要值，你可以做一个列表理解......

in_array = 结果中 x 的 [x['content_reference']['引用']

然后您将拥有值列表的in_array：['160'， '159'， '162']