Question

我在model.py中有以下内容：

        DECLARE @defaultLanguage NVARCHAR(5)

        SET @defaultLanguage = (SELECT LanguageCode FROM LANGUAGE WHERE IsDefault = 1)

        SELECT
            c.Id,
            c.Name,
            c.OrgNr,
            c.UserId,
            c.Address,
            c.PostalArea,
            c.County,
            c.Country,
            c.Description,
            c.DescriptionFull,
            c.Telephone,
            c.Email,
            c.Website,
            c.IsApproved,
            s.Id,
            ISNULL(tr.Name, def.Name) Name

          FROM Company c

          INNER JOIN CompanyService cs on cs.CompanyId = C.Id

          INNER JOIN Service s on s.Id = cs.ServiceId 

          LEFT OUTER JOIN ServiceTranslation tr
            ON s.Id = tr.ServiceId AND tr.LanguageCode = @userLanguage
          -- join default language of the service:

          LEFT OUTER JOIN ServiceTranslation def
            ON s.Id = def.ServiceId AND def.LanguageCode = @defaultLanguage 

          WHERE c.IsApproved = 1 

          AND
          c.Id IN 
          (
              SELECT c1.Id FROM Company c1

              INNER JOIN CompanyService cs1 on cs1.CompanyId = c1.Id

              INNER JOIN Service s1 on s1.Id = cs1.ServiceId 

              INNER JOIN ServiceTranslation tr1
                ON s1.Id = tr1.ServiceId AND tr1.LanguageCode = @userLanguage
              -- join default language of the service:

              INNER JOIN ServiceTranslation def1
                ON s1.Id = def1.ServiceId AND def1.LanguageCode = @defaultLanguage



               AND s1.IsApproved = 1 AND  ISNULL(tr1.Name, def1.Name) LIKE '%' + @searchQuery + '%'
          )

我还有一个相应的表单，在填写和汇总时，可以正确地保存到数据库中。

我不明白的是from django.db import models from django.contrib.auth.models import User from django.db.models.signals import post_save from django.dispatch import receiver class Profile(models.Model): user = models.OneToOneField(User, on_delete=models.CASCADE) university = models.CharField(max_length=30, blank=True) birth_date = models.DateField(null=True, blank=True) ROLE = ( ('CUSTOMER', 'User'), # (value to be set on model, human readable value) ('WORKER', 'Worker'), ) role = models.CharField(max_length = 20, choices = ROLE, default = 'USER') def __str__(self): return self.user.username @receiver(post_save, sender=User) def create_user_profile(sender, instance, created, **kwargs): if created: Profile.objects.create(user=instance) @receiver(post_save, sender=User) def save_user_profile(sender, instance, **kwargs): instance.profile.save()这是如何运作的？对我来说，它似乎应该是instance.profile.save()，因为instance.Profile.save()存在。我不确定这个小写Profile来自何处？

Answer 1

在Django中，默认情况下，反向访问者使用小写中的相关模型名称定义。

由于您的Profile模型与one-to-one模型之间存在User关系，您可以访问属于User实例的配置文件实例（例如用户）为user.profile。

您可以使用参数覆盖此命名，您可以使用关键字参数related_name在模型定义中定义OneToOneField。

class Profile(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE, related_name='myprofile')

现在，您可以通过user.myprofile

进行访问

请参阅Django文档here

顺便提一下，当您通过User实例访问用户的个人资料时要小心。如果没有与Profile实例关联的User记录，则会引发DoesNotExist异常。

这个模型有效，但我不明白信号是如何工作的

1 个答案: