Django - 如何通过中介链接到遗留数据库？ [英] Django - How to link to a legacy database via intermediary?

问题描述

我必须将遗留设计与我的Django项目进行整合，我正在寻找一些关于使用中介的建议。现有的设计工作，但现在我需要通过第三个表过滤该项目。

英文 - 我有一个组织（Django），它指向许多项目）。但是所有的项目都不是指该组织。我有一个第三个表ProjectMap是通过一个触发器来构建的。它对应于一个项目的Organization.name。

如何粘合在一起，以便我这样做。

  projects = Organization.objects.get（pk = 1）.projects.all（）
  

它不会得到所有项目只是在第三个表中匹配的项目。这是我到目前为止..

顺便说一句，如果有一个更好的策略，我都耳朵

 类组织（models.Model）：
 name = models.CharField（max_length = 32）
 projects = models.ManyToManyField （项目）
 
类项目（models.Model）：
这是项目信息页面
 
注意：'id'确实存在，是$ p 

 result_number = models.IntegerField（null = True，db_column ='LBLDGRUNNO'，blank = True）
 building_number = models.IntegerField（db_column ='LBLDGNO' ）
 name = models.CharField（max_length = 150，db_column ='SPIBLGNAME'，blank = True）
 
 class Meta：
 db_table = u'PROJINFO'
 managed = False 
 
 class ProjectMap（models.Model）：
 projinfo_table_id = models.IntegerField（null = True）项目
的名称'id'$ name = models.CharField（max_length = 128，null = True）＃'name'在组织$ b $中b  

非常感谢！

解决方案

不知道这是你的问题，但是您可以在ManyToManyField上使用通过调用来定义一个中间表：

 类组织（models.Model）：
 name = models.CharField（max_length = 32）
 projects = models.ManyToManyField ，through =ProjectOrganisation）
 
 class Project（models.Model）：
 #Stuff Here 
 
 class ProjectOrganisation（models.Model）：
 project = models.ForeignKey（Project）
 organization = models.ForeignKey（Organization）
＃其他字段
  

Django无论如何都会自动使用manytomany字段，只要你想添加额外的字段，这是这样做的。

I have to integrate a legacy design with my Django project and I am looking for some advice on using an intermediary. The existing design works but now I need to filter the Project by a third table.

In english - I have a Organization (Django) and which points to many Projects (Legacy). But all of the Project don't refer to that Organization. I have a third table ProjectMap which was build via a Trigger to address that. It corresponds the Organization.name to a project.

How do I glue this together in order allow me to do this.

projects = Organization.objects.get(pk=1).projects.all()

And it won't get ALL of the projects just the ones which match in the third table. Here is what I have so far..

By the way if anyone has a better strategy I'm all ears

class Organization(models.Model):
    name = models.CharField(max_length=32)
    projects = models.ManyToManyField(Project)

class Project(models.Model):
    """This is the project info page..

    Note: 'id' does exist and is the pk.
    """
    result_number = models.IntegerField(null=True, db_column='LBLDGRUNNO', blank=True) 
    building_number = models.IntegerField(db_column='LBLDGNO') 
    name = models.CharField(max_length=150, db_column='SPIBLGNAME', blank=True)

    class Meta:
        db_table = u'PROJINFO'
        managed = False

class ProjectMap(models.Model):
    projinfo_table_id = models.IntegerField(null=True) # 'id' of Project
    name = models.CharField(max_length=128, null=True) # 'name' in Organization

Thanks so much!

解决方案

Not sure if this is what your asking, but you can use the through call on the ManyToManyField to define an intermediate table:

class Organization(models.Model):
    name = models.CharField(max_length=32)
    projects = models.ManyToManyField(Project, through="ProjectOrganisation")

class Project(models.Model):
    #Stuff Here

class ProjectOrganisation(models.Model):
    project = models.ForeignKey(Project)
    organization = models.ForeignKey(Organization)
    #Other Fields Here

Django does this automatically with manytomany fields anyway, just if you want to add extra fields, this is the way to do it.

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