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django-不允许在字段上查找不支持的JSONField或join

django-jsonfield django-views django-models python-3.x django

0

Pankaj Sharma · 技术社区 · 7 年前

我的模型中有一个Json字段-

class Product(models.Model):
    ...
    detailed_stock           = JSONField(load_kwargs={'object_pairs_hook': collections.OrderedDict},default=dict)

{
  "total":0,
  "5[1]":0
}

我正在尝试筛选total=0的对象,为此我尝试了-

Product.objects.filter(detailed_stock__total = 0) 但这会带来错误-

Unsupported lookup 'total' for JSONField or join on the field not permitted.

documentation 允许使用以下代码。

这是完全的回溯-

Traceback (most recent call last):
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\core\handlers\exception.py", line 35, in inner
    response = get_response(request)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\core\handlers\base.py", line 128, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\core\handlers\base.py", line 126, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\views\generic\base.py", line 69, in view
    return self.dispatch(request, *args, **kwargs)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\braces\views\_access.py", line 102, in dispatch
    request, *args, **kwargs)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\views\generic\base.py", line 89, in dispatch
    return handler(request, *args, **kwargs)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\views\generic\list.py", line 142, in get
    self.object_list = self.get_queryset()
  File "c:\Users\lenovo\Desktop\My_Django_Stuff\bekaim\accounts\views.py", line 142, in get_queryset
    queryset = Product.objects.filter(detailed_stock__total = 0)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\db\models\query.py", line 836, in filter
    return self._filter_or_exclude(False, *args, **kwargs)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\db\models\query.py", line 854, in _filter_or_exclude
    clone.query.add_q(Q(*args, **kwargs))
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1253, in add_q
    clause, _ = self._add_q(q_object, self.used_aliases)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1271, in _add_q
    current_negated, allow_joins, split_subq)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1277, in _add_q
    split_subq=split_subq,
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1215, in build_filter
    condition = self.build_lookup(lookups, col, value)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1069, in build_lookup
    lhs = self.try_transform(lhs, name)
  File "C:\Users\lenovo\AppData\Local\conda\conda\envs\myDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1115, in try_transform
    (name, lhs.output_field.__class__.__name__))
django.core.exceptions.FieldError: Unsupported lookup 'total' for JSONField or join on the field not permitted.
[31/Dec/2018 16:13:37] "GET /accounts/product-list/?clean=outofstock HTTP/1.1" 500 150927

我在网上搜索,但找不到解决方案,请帮助。

1 回复 | 直到 7 年前

1

9

escaped 7 年前

我想你正在使用 django-jsonfield load_kwargs={'object_pairs_hook': collections.OrderedDict} 而不是 django.contrib.postgres.fields.JSONField .

django-jsonfield dict 类型,并基于一个简单的 TextField product.detail_stock str 转换为 字典 json.loads() 由该领域本身。因此,您只能使用以下操作 icontains 和 contains 用于查询该字段。

如果您使用postgres作为数据库,则可以充分利用 django.contrib.postgres.fields.JSONField 正如文件所述。但您必须导入正确的 JSONfield 利用 django.contrib.postgres.fields import JSONField .

有一个解决办法 mysql (套餐 django-mysql )也是。

2

0

incarnadine 5 年前

from json_field import JSONField

那么您就不能从SQL查找中获益。如上所述,JSONField覆盖仅限文本字段。它验证JSONformat并将其转储为字符串。

class JSONField(models.TextField):
    """ Stores and loads valid JSON objects. """

from django.db import models
data = models.JSONField(null=True)