Python 如何使用外键约束从django模型中检索值?
我有两种型号,一种是Python 如何使用外键约束从django模型中检索值?,python,django,django-models,django-templates,Python,Django,Django Models,Django Templates,我有两种型号,一种是 class NewsLikes(models.Model): id = models.IntegerField(db_column="id", max_length=11, help_text="") userId = models.ForeignKey(Users, db_column='userId', max_length=11, help_text="") newsId = models.ForeignKey(NewsMappings, db_column='new
class NewsLikes(models.Model):
id = models.IntegerField(db_column="id", max_length=11, help_text="")
userId = models.ForeignKey(Users, db_column='userId', max_length=11, help_text="")
newsId = models.ForeignKey(NewsMappings, db_column='newsMappingId', max_length=11, help_text="")
createdAt = models.DateTimeField(db_column='createdAt', auto_now=True, help_text="
另一种模式是
class NewsMappings(models.Model):
id = models.IntegerField(db_column="id", max_length=11, help_text="")
newsId = models.ForeignKey(News, db_column='newsId', max_length=11, help_text="")
boardId = models.ForeignKey(Boards, db_column='boardId', max_length=11, help_text="")
isWallPost = models.BooleanField(db_column="isWallPost", default=False, help_text="")
模型news-like包含新闻映射的外键。我在django模板中将新闻映射作为上下文传递,我想计算关于新闻映射的新闻类id的数量,并将其显示在模板上。有一个django文档可供参考 其中解释了外键之间的关系映射。在您的情况下,如果您正在寻找每个NewsLikeID的所有NewsMappings列表,那么请检查以下内容
NewsLikes.objects.filter(NewsMapping__newsId='SomeNewsID')