在django操作数据库的时候如何找出内容不为空的数据呢?
from django.db.models import Q
class Index(VIew):
def get(self, request):
userObj = models.Asset.objects.filter(~Q(asset_id = '')
return HttpResponse('yes')
上面代码中的models.Asset.objects.filter(~Q(nick = ”)则是使用Q函数去找出nick不为空的数据,主要使用~Q
补充知识:Django报错 HINT: Add or change a related_name argument to the definition for ‘GodownentryReturn.suppl
Unhandled exception in thread started by <function wrapper at 0x05569030 Traceback (most recent call last): File “G:\workspace\pycharm\carwin\carwin_env\lib\site-packages\django\utils\autoreload.py”, line 226, in wrapper fn(*args, **kwargs) File “G:\workspace\pycharm\carwin\carwin_env\lib\site-packages\django\core\management\commands\runserver.py”, line 116, in inner_run self.check(display_num_errors=True) File “G:\workspace\pycharm\carwin\carwin_env\lib\site-packages\django\core\management\base.py”, line 472, in check raise SystemCheckError(msg) django.core.management.base.SystemCheckError: SystemCheckError: System check identified some issues: ERRORS: article.GodownentryReturn.supplier: (fields.E304) Reverse accessor for ‘GodownentryReturn.supplier’ clashes with reverse accessor for ‘GodownentryReturn.supplier’. HINT: Add or change a related_name argument to the definition for ‘GodownentryReturn.supplier’ or ‘GodownentryReturn.supplier’. part.GodownentryReturn.supplier: (fields.E304) Reverse accessor for ‘GodownentryReturn.supplier’ clashes with reverse accessor for ‘GodownentryReturn.supplier’. HINT: Add or change a related_name argument to the definition for ‘GodownentryReturn.supplier’ or ‘GodownentryReturn.supplier’.
原因:
因为在一个表中多次引用某个外键表,而且没有指定唯一的releated_name,而导致的。
解决方案:
将同一个表中外键,增加不同的releated_name。
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