如何在Django中查询多到多个关系

Question

我有很多关于关系的作者，“Django邮报”。

我想要的是，执行一个查询并获得显示在表中的结果。

我怎样才能执行这个动作？多谢你们的支持。

# models.py

class Author(models.Model):
    name = models.CharField(max_length=200)
    email = models.EmailField()

class Post(models.Model):
    authors = models.ManyToManyField(Author)
    headline = models.CharField(max_length=255)
    body_text = models.TextField(null=True, blank=True)

表

+------------+----------------+--------------------+
| author_id  | name           | email              |
+============+================+====================+
| 1          | John Doe       | jdoe@test.com      |
+------------+----------------+--------------------+
| 2          | Peter Smith    | psmith@test.com    |
+------------+----------------+--------------------+
| 3          | Karen Jackson  | kjackson@test.com  |
+------------+----------------+--------------------+


+----------+--------------------+--------------------------------------+
| post_id  | headline           | body                                 |
+==========+====================+======================================+
| 1        | Worpress tutorial  | Lorem Ipsum is simply dummy text...  |
+----------+--------------------+--------------------------------------+
| 2        | Developer news     | Lorem Ipsum is simply dummy text...  |
+----------+--------------------+--------------------------------------+
| 3        | Science news       | Lorem Ipsum is simply dummy text...  |
+----------+--------------------+--------------------------------------+

结果表

+----------------+------------+----------------+---------------------+----------+--------------------+-----------+
| autor_post_id  | author_id  | name           | email               | post_id  | headline           | body      |
+================+============+================+=====================+==========+====================+===========+
| 1              | 1          | John Doe       | jdoe@test.com       | 1        | Worpress tutorial  | Lorem...  |
+----------------+------------+----------------+---------------------+----------+--------------------+-----------+
| 2              | 2          | Peter Smith    | psmith@test.com     | 1        | Worpress tutorial  | Lorem...  |
+----------------+------------+----------------+---------------------+----------+--------------------+-----------+
| 3              | 1          | John Doe       | jdoe@test.com       | 2        | Developer news     | Lorem...  |
+----------------+------------+----------------+---------------------+----------+--------------------+-----------+
| 4              | 2          | Peter Smith    | psmith@test.com     | 2        | Developer news     | Lorem...  |
+----------------+------------+----------------+---------------------+----------+--------------------+-----------+
| 5              | 3          | Karen Jackson  | kjackson@test.com   | 3        | Science news       | Lorem...  |
+----------------+------------+----------------+---------------------+----------+--------------------+-----------+
| 6              | 1          | John Doe       | jdoe@test.com       | 3        | Science news       | Lorem...  |
+----------------+------------+----------------+---------------------+----------+--------------------+-----------+

Answer 1

这很简单：

Post.authors.through.objects.values_list('pk', 'author_id', 'author__name', 'author__email', 'post_id', 'post__headline', 'post__body')

其他的可能性是-处理对象：

queyset=Post.authors.through.objects.select_related('author', 'post')

在queryset中，您可以找到具有有界作者和post的通透对象。