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Python Django分组以查找计数_Python_Django - Fatal编程技术网

Python Django分组以查找计数

Python Django分组以查找计数,python,django,Python,Django,我有下面给出的模型 class Page(models.Model): name = models.CharField(max_length=150) city = models.CharField(max_length=50) country = models.ForeignKey(Country) class Country(models.Model): name = models.CharField(max_length=150) 我所需要的就是得到每个

我有下面给出的模型

class Page(models.Model):
    name = models.CharField(max_length=150)
    city = models.CharField(max_length=50)
    country = models.ForeignKey(Country)

class Country(models.Model):
    name = models.CharField(max_length=150)
我所需要的就是得到每个国家的页数。i、 e

{country1:3,country2:4}

(特定于国家/地区的页数)


是否可以根据所示的国家/地区外键获取页面的计数?

您可以使用计数进行注释:

pages = Page.objects.annotate(num_countries=Count('country'))
pages[0].num_countries  # 3
pages[1].num_countries  # 4
聚合API文档中有关于此的详细信息