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  • Django 中 related_name/related_query_name 的区别

    related_name/related_query_name 一般出现在有 Foreignkey  或者 Manytomang 字段的时候

    一 一般查询

    class Department(models.Model):
       title = models.CharField(verbose_name='部门',max_length=32)
    
    class UserInfo(models.Model):
       depart = models.ForeignKey(verbose_name='部门',to='Department')
       user = models.CharField(verbose_name='用户',max_length=32)
       pwd = models.CharField(verbose_name='用户', max_length=32)

    以前查询

    正向查询---用点
     user_object = UserInfo.objects.get(id=1)
     user_object.depart
    反向查询---表名小写+set
     depart_object = Department.objects.get(id=9)
     depart_object.userinfo_set.all()

    二  如果是 related_query_name

    class Department(models.Model):
     title = models.CharField(verbose_name='部门',max_length=32)
    
    class UserInfo(models.Model):
     depart=models.ForeignKey(verbose_name='部门',to='Department',related_query_name="u")
     user = models.CharField(verbose_name='用户',max_length=32)
     pwd = models.CharField(verbose_name='用户', max_length=32)

    再查询

    正向查询---用点
     user_object = UserInfo.objects.get(id=1)
     user_object.depart
    反向查询---表名小写+set
     depart_object = Department.objects.get(id=9)
     depart_object.u_set.all()

    三 如果是 related_name的话

    class Department(models.Model):
     title = models.CharField(verbose_name='部门',max_length=32)
    
    class UserInfo(models.Model):
     depart=models.ForeignKey(verbose_name='部门',to='Department',related_name="u")
     user = models.CharField(verbose_name='用户',max_length=32)
     pwd = models.CharField(verbose_name='用户', max_length=32)

    再查询

    正向查询---用点
     user_object = UserInfo.objects.get(id=1)
     user_object.depart
    反向查询---表名小写+set
     depart_object = Department.objects.get(id=9)
     depart_object.u.all()
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  • 原文地址:https://www.cnblogs.com/a438842265/p/12595622.html
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