对于扩展的信息，我应该使用Django的多表继承或显式的OneToOneField [英] For extended information, should I use Django's Multi-table Inheritance or an explicit OneToOneField

问题描述

我在模型上有一些不总是填写的字段（例如，直到项目结束之前的实际完成日期和成本）。因此，我以为我会将模型分成两部分：

I have some fields on a model that won't always be filled in (e.g., the actual completion date and costs until the project is over). Because of this, I thought I'd split the model into two:

1. 模型＃1 ：密集表包含经常搜索和始终填写的字段


2. 模型＃2 ：包含不常搜索但不总是填写字段的稀疏表

1. Model #1: Dense table containing frequently searched and always completed fields
2. Model #2: Sparse table containing infrequently searched and not always completed fields

问题

Questions

1. 我正在思考将其分成两个模型/表？ li>
   
2. 我应该使用Django的多表继承，还是应该明确定义一个 OneToOneField ？为什么？

1. Am I thinking correctly in splitting this into two models/tables?
2. Should I use Django's Multi-table Inheritance, or should I explicitly define a OneToOneField? Why?

配置

• Django版本1.3.1



class Project(models.Model):
    project_number = models.SlugField(max_length=5, blank=False,
            primary_key=True)
    budgeted_costs = models.DecimalField(max_digits=10, decimal_places=2)

class ProjectExtendedInformation(Project):
    submitted_on = models.DateField(auto_now_add=True)
    actual_completion_date = models.DateField(blank=True, null=True)
    actual_project_costs = models.DecimalField(max_digits=10, decimal_places=2,
            blank=True, null=True)





使用显式 OneToOneField





Using an Explicit OneToOneField

class Project(models.Model):
    project_number = models.SlugField(max_length=5, blank=False,
            primary_key=True)
    budgeted_costs = models.DecimalField(max_digits=10, decimal_places=2)

class ProjectExtendedInformation(models.Model):
    project = models.OneToOneField(CapExProject, primary_key=True)
    submitted_on = models.DateField(auto_now_add=True)
    actual_completion_date = models.DateField(blank=True, null=True)
    actual_project_costs = models.DecimalField(max_digits=10, decimal_places=2,
            blank=True, null=True)




推荐答案

你在这里主要处理苹果和苹果。 Django的MTI实现（多表继承）使用隐式的OneToOneField。

You're essentially dealing with apples and apples here. Django's implementation of MTI (multi-table inheritance) uses an implicit OneToOneField.

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