Django爲子類設計的模型/數據庫設計

Question

好吧，我在描述的狗屎。這是一個關係診斷。 relationship diag http://img248.imageshack.us/img248/3568/surveyrel.jpg

在Django中我做了我的車型，如：

from django.db import models 
from datetime import datetime 

class Survey(models.Model): 
    name = models.CharField(max_length=100) 
    pub_date = models.DateTimeField('date published',default=datetime.now) 
    def __unicode__(self): 
     return self.name 

# This model should be abstracted by a more specific model 
class Section(models.Model): 
    survey = models.ForeignKey(Survey) 
    name = models.CharField(max_length=100) 
    def __unicode__(self): 
     return self.name 

# Models for supporting the 'ratings' mode 
class RatingSection(Section): 
    pass 

class RatingQuestion(models.Model): 
    section = models.ForeignKey(RatingSection) 
    name = models.CharField(max_length=255) 
    def __unicode__(self): 
     return self.name 

class RatingAnswer(models.Model): 
    section = models.ForeignKey(RatingSection) 
    name = models.CharField(max_length=60) 
    def __unicode__(self): 
     return self.name 

class RatingVotes(models.Model): 
    question = models.ForeignKey(RatingQuestion) 
    answer = models.ForeignKey(RatingAnswer) 
    votes = models.PositiveIntegerField(default=0) 
    def __unicode__(self): 
     return self.votes + self.answer.name + ' votes for ' + self.question.name 

# Models for supporting the 'multichoice' mode 
class MultiChoiceSection(Section): 
    can_select_multiple = models.BooleanField() 

class MultiChoiceQuestion(models.Model): 
    section = models.ForeignKey(MultiChoiceSection) 
    name = models.CharField(max_length=255) 
    def __unicode__(self): 
     return self.name 

class MultiChoiceAnswer(models.Model): 
    section = models.ForeignKey(MultiChoiceSection) 
    name = models.CharField(max_length=60) 
    votes = models.PositiveIntegerField(default=0) 
    def __unicode__(self): 
     return self.name 

的問題是，我幾乎可以肯定，這不是做正確的方式，即使是這樣，我可以」 t解決了如何讓Django中的管理區域向用戶顯示一個選擇，詢問他們想要的部分子類型。

什麼是構建這種模型的最佳方法？

Answer 1

你也可以有一個部分類，有一個屬性type，可以是評級或多選 - 這將被顯示在管理員然後作爲選擇框。
但我認爲你應該看看Django的可能性創造抽象的模型：http://docs.djangoproject.com/en/dev/topics/db/models/#id6

class Section(models.Model): 
    survey = models.ForeignKey(Survey) 
    name = models.CharField(max_length=100) 

    class Meta: 
     abstract = True  # no db table created for this model 

    def __unicode__(self): 
     return self.name 


class RatingSection(Section): 
    pass 

class MultiChoiceSection(Section): 
    can_select_multiple = models.BooleanField()