related_name和related_query_name举例区别

举例，一

class UserInfo(models.Model):
    nickname = models.CharField(max_length=32)
    username = models.CharField(max_length=32)
    password = models.CharField(max_length=64)

    gender_choices = (
        (1,'男'),
        (2,'女'),
    )
    gender = models.IntegerField(choices=gender_choices)

ralated_query_name　

class U2U(models.Model):
    g = models.ForeignKey('UserInfo',ralated_query_name='a')
    b = models.ForeignKey('UserInfo',ralated_query_name='b')

   # ralated_query_name

  #  obj.对象男.b_set.all()
  #  obj.对象女.a_set.all()

ralated_name

class U2U(models.Model):
    g = models.ForeignKey('UserInfo',ralated_name='a')
    b = models.ForeignKey('UserInfo',ralated_name='b')

   # ralated_name

  #  obj.对象男.b.all()
  #  obj.对象女.a.all()

　回顾以往例子：反向查找别名替换

class UserType(models.Model):
    title = models.CharField(max_length=32)

class User(models.Model):
    username = models.CharField(max_length=32)
    ut = models.ForeignKey('UserType',related_name='xxx')

## related_name='xxx'：

反向：小写表名user_set ===>xxx

## related_query_name = 'xxx'
反向：user_set==>xxx_set

推荐用：

 ut = models.ForeignKey('UserType',related_name='users')

    obj.users

#M2M自关联的特性：

##1，obj.m  前一列
##2，obj.userinfo_set 后一列

obj = models.UserInfo.objects.filter(id=1).first()

#男---前一列
obj.m    =>select xx from xx where  from_userinfo_id = 1

#女----后一列
obj.userinfo_set =>select xx from xx where to_userinfo_id = 1

　　

定义：

前面列：男生ID

后面列：女生ID

应用：　　

#男生obj
obj = models.UserInfo.objects.filter(id=1).first()
# 根据男生id=1，查找关联的所有女生
obj.m.all()
 

#女生obj
obj = models.UserInfo.objects.filter(id=4).first()
#根据女生id=4，查找关联的所有男生
obj.userinfo_set.all()

　　# FK自关联