如何在 Django 中从 OneToOneField 填充模型的新字段？

Question

在Django 3.1.2中，我想将OneToOneField中的数据复制到多个字段。

我想更改

class A(models.Model):
name = models.TextField()
description = models.TextField()
class B(models.Model):
a = models.OneToOneField(A, on_delete=models.CASCADE, related_name='b_a')

至

class A(models.Model):
name = models.TextField()
description = models.TextField()
class B(models.Model):
name = models.TextField()
description = models.TextField()

同时保留现有数据。

感谢您提前抽出时间！

Answer 1

步骤1

class A(models.Model):
name = models.TextField()
description = models.TextField()
class B(models.Model):
a = models.OneToOneField(A, on_delete=models.CASCADE, related_name='b_a')
name = models.TextField()
description = models.TextField()

步骤2

makemigrations
migrate
def sync():
for i in B.objects.all():
i.name = i.a.name
i.description = i.a.description
i.save()

步骤3

change model B
class B(models.Model):
name = models.TextField()
description = models.TextField()

步骤4

makemigrations
migrate