Django“无法添加或更新子行：外键约束失败” [英] Django "Cannot add or update a child row: a foreign key constraint fails"

问题描述

我有一个模型优惠券和一个模型照片与 ForeignKey 给它：

  class Photo（models.Model）：
 coupon = models.ForeignKey 
 related_name ='description_photos'
 title = models.CharField（max_length = 100）
 image = models.ImageField（upload_to ='images'）
  

我在管理员中设置了内联，所以现在我可以从管理员添加照片到优惠券。

我尝试添加一个，上传成功，但是我得到Django的调试页面，出现这个错误：

 code> IntegrityError at / admin / coupon / coupon / 321 / 
（1452，'无法添加或更新子行：外键约束失败（`my_project`.`coupon_photo`，CONSTRAINT`coupon_id_refs_id_90d7f06` FOREIGN KEY（`coupon_id`）参考`coupon_coupon`（`id`））'）
  

什么是这个怎么解决这个问题？ / p>

（如果重要，这是一个MySQL数据库。）

编辑：我在一个稍微不同的数据集的Sqlite3数据库上尝试过，它的工作，所以也许在我当前的数据库中有松散的数据？我如何找到它并删除它？

解决方案

我的一些表在InnoDB中，有些在MyISAM ...我将所有内容更改为MyISAM，问题已解决。

I have a model Coupon, and a model Photo with a ForeignKey to it:

class Photo(models.Model):
    coupon = models.ForeignKey(Coupon,
                               related_name='description_photos')
    title = models.CharField(max_length=100)
    image = models.ImageField(upload_to='images')

I set up inlines in the admin so now I'm able to add photos to a coupon from the admin.

I attempt to add one, and upload is successful, but then I get Django's debug page with this error:

IntegrityError at /admin/coupon/coupon/321/
(1452, 'Cannot add or update a child row: a foreign key constraint fails (`my_project`.`coupon_photo`, CONSTRAINT `coupon_id_refs_id_90d7f06` FOREIGN KEY (`coupon_id`) REFERENCES `coupon_coupon` (`id`))')

What is this and how can I solve this problem?

(If it matters, this is a MySQL database.)

EDIT: I tried it on an Sqlite3 database that has a slightly different dataset, and it worked, so perhaps there's loose data in my current DB? How can I find it and delete it?

解决方案

Some of my tables were in InnoDB and some were in MyISAM... I changed everything to MyISAM and the problem was solved.

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