查询集上的自定义删除方法 [英] Custom delete method on queryset

问题描述

我的Django模型在 delete 方法中具有自定义逻辑。因此，由于我想确保在我调用此逻辑在我的 queryset 上调用delete，我编写了自己的 queryset delete。

My Django model has custom logic in the delete method. Therefore since I wane to make sure that this logic is called when I call delete on my queryset, I wrote my own queryset delete.

class MyQuerySet(QuerySet):
    # Do we have to be any fancier here?
    def delete(self):
        for m in self:
            m.delete()

，我的问题是，除了在每个实例上迭代并调用 delete 之外，我还需要做其他更有趣的事情吗？

and my question is do I have to do anything fancier than iterating and calling delete on each instance?

推荐答案

您应该清除结果缓存，以便如果查询集将被重用，则将再次评估数据库查询。

You should clear the result cache so if the queryset will be reused then DB query will be evaluated again.

还必须设置两个属性：

• alters_data = True 阻止调用此属性模板中的方法；



• queryset_only = True 从用作管理器的查询集中隐藏此方法。

• alters_data=True prevents calling this method from templates;

• queryset_only=True hides this method from queryset used as manager.

类MyQuerySet（QuerySet）：

class MyQuerySet(QuerySet):

def delete(self):
    for m in self:
        m.delete()
    self._result_cache = None    
delete.alters_data = True
delete.queryset_only = True

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