通过@property订购Django queryset [英] Ordering Django queryset by an @property

问题描述

我试图通过在模型中定义的属性来排序查询集，但不能确定最佳的方法。这是以下属性：

I'm trying to order a query set by a property I defined in the model, but not sure the best way to do this. Here's the property:

@property
def name(self):
    if self.custom_name:
        return self.custom_name
    else:
        return self.module_object.name

基本上，我想做一个：

things = Thing.objects.all().order_by('-name')

但当然，在呈现时会获得一个Caught FieldError：无法将关键字'name'解析为字段

but of course getting a Caught FieldError while rendering: Cannot resolve keyword 'name' into field.

任何想法？

编辑：我明白我不能这样排序 @property 不是数据库字段。我的问题是如何排序，因为 @property 不是数据库字段。

I understand that I can't sort this way because the @property isn't a database field. My question is how to sort given that @property isn't a database field.

推荐答案

您不能这样做，因为该属性不在MySQL中，而是在您的python代码中。如果你真的想这样做，你可以在客户端（虽然会很慢）：

You can't do that because that property is not in MySQL, but in your python code. If you really want to do this, you can on the client-side(though it will be very slow):

sorted(Thing.objects.all(), key=lambda t: t.name)

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