先設(shè)定一個關(guān)系模型如下：
from django.db import modelsclass Blog(models.Model): name = models.CharField(max_length=100) tagline = models.TextField() def __str__(self): return self.name class Author(models.Model): name = models.CharField(max_length=50) email = models.EmailField() def __str__(self): return self.name class Entry(models.Model): blog = models.ForeignKey(Blog) headline = models.CharField(max_length=255) body_text = models.TextField() authors = models.ManyToManyField(Author) def __str__(self): return self.headline
上面的數(shù)據(jù)關(guān)系很明晰,Entry中有Blog和Author的外鍵,如果要在Entry中讀取blog和author的數(shù)據(jù)很容易：
entry = Entry.objects.all()for e in entry: blog = e.blog author = e.authors
要在Blog和Author中讀取Entry也可以：
blog = Blog.objects.all()entry = blog.entry_set.all() author = Author.objects.all()entry = author.entry_set.all()
下面通過entry使blog和author互相讀取，比如要知道一個blog的Author只需如下：
blogs = Blog.objects.all()for blog in blogs: if blog.name== “我們想要查詢的博客的name” author = blog. entry_set.authors
要查詢一個author的所有blog如下：
authors = Author.objects.all()blogs = [] for author in authors: if author.name== “我們想要查詢的Author的name” for entry in author.entry_set.all(): blogs.append(entry. blog)
以上這篇django 外鍵model的互相讀取方法就是小編分享給大家的全部內(nèi)容了，希望能給大家一個參考，也希望大家多多支持VEVB武林網(wǎng)。
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