Django查询Json结果

时间:2017-04-10 13:09:53

标签: python json django

在我的代码中,我创建了这个'dict'类型数组:

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

它保存在数据库表格列 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'

我写过这个数据库查询:

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]

它给出了结果:

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

使用此 FOR 循环,我尝试访问content_reference ['参考']的所有值(即160,159,162)并将它们放入数组中的 in_array

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

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

回溯:

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'

2 个答案:

答案 0 :(得分:2)

你可以做到

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

答案 1 :(得分:1)

如果您只想要这些值,您可以进行列表理解......

in_array = [x [&#39; content_reference&#39;] [&#39;参考&#39;] for x in result]

你的in_array将包含值列表: [&#39; 160&#39;,&#39; 159&#39;,&#39; 162&#39;]