Use of meta class in django

问题

Can someone please explain why is meta class used in the following example.

Ex:

Class Employee (models.Model):
    name = models.ForeignKey(name)
    Gender = models.IntegerField()


    class Meta:
        ordering = ["Gender"]

Thanks.

回答1:

Because author/programmer wants to sort results by value of Gender field.

回答2:

Django models use the Meta class to contain extra information about the model that would not necessarily be appropriate to contain within the model class itself. Note that this is not the same as Python's metaclass; that is a completely different topic.

In this case it ordering or sorting the queries to this model by field "Gender"

回答3:

In this case it defines the default field for ordering if you don't provide ORDER_BY in your query.

回答4:

It is explained in Django Documentation for Models

https://docs.djangoproject.com/en/dev/topics/db/models/

Give your model metadata by using an inner class Meta, like:

Class Employee (models.Model):
    ....

    class Meta:
        ordering = ["attribute-X"]

Another useful option can be used in class Meta is verbose_name.

来源：https://stackoverflow.com/questions/2146363/use-of-meta-class-in-django