Django loaddata UNIQUE约束失败

Question

我正在运行python manage.py loaddata 'path/to/mydata.json'一个空数据库(User并且UserProfile表已创建但未填充),但是,我收到以下错误:

django.db.utils.IntegrityError: Problem installing fixture 'path/to/mydata.json': Could not load myapp.UserProfile(pk=1): UNIQUE constraint failed: myapp_userprofile.user_id

我检查了(即使在运行此命令后)并且根本没有填充数据库.那么怎么能给出pk不是唯一的错误呢？

如果相关,UserProfile只需User使用此处OneToOneField建议的关系扩展默认模型.

这mydata.json包含:

[
    {
        "model": "auth.user",
        "pk": 1,
        "fields": {
            "password": "pbkdf2_sha256..",
            "last_login": "2016-10-22T15:19:46.926Z",
            "is_superuser": true,
            "username": "thesuperuser",
            "first_name": "",
            "last_name": "",
            "email": "a@a.co",
            "is_staff": true,
            "is_active": true,
            "date_joined": "2016-10-22T14:48:27.394Z",
            "groups": [],
            "user_permissions": []
        }
    },
    {
        "model": "auth.user",
        "pk": 2,
        "fields": {
            "password": "pbkdf2_sha256..",
            "last_login": null,
            "is_superuser": false,
            "username": "user1",
            "first_name": "User",
            "last_name": "One",
            "email": "",
            "is_staff": false,
            "is_active": true,
            "date_joined": "2016-10-22T15:20:32Z",
            "groups": [],
            "user_permissions": []
        }
    },
    {
        "model": "auth.user",
        "pk": 4,
        "fields": {
            "password": "pbkdf2_sha256..",
            "last_login": null,
            "is_superuser": false,
            "username": "user3",
            "first_name": "User",
            "last_name": "Three",
            "email": "",
            "is_staff": false,
            "is_active": true,
            "date_joined": "2016-10-22T15:21:09Z",
            "groups": [],
            "user_permissions": []
        }
    },
    {
        "model": "auth.user",
        "pk": 3,
        "fields": {
            "password": "pbkdf2_sha256..",
            "last_login": null,
            "is_superuser": false,
            "username": "user2",
            "first_name": "User",
            "last_name": "Two",
            "email": "",
            "is_staff": false,
            "is_active": true,
            "date_joined": "2016-10-22T15:21:03Z",
            "groups": [],
            "user_permissions": []
        }
    },
    {
        "model": "myapp.userprofile",
        "pk": 1,
        "fields": {
            "user": 1,
            "money": 100
        }
    },
    {
        "model": "myapp.userprofile",
        "pk": 2,
        "fields": {
            "user": 2,
            "money": 100
        }
    },
    {
        "model": "myapp.userprofile",
        "pk": 3,
        "fields": {
            "user": 3,
            "money": 100
        }
    },
    {
        "model": "myapp.userprofile",
        "pk": 4,
        "fields": {
            "user": 4,
            "money": 100
        }
    }
]

谢谢你的帮助,

Answer 1

今天（2020 年 4 月 24 日）我在Django 2.2 上遇到了类似的问题

我的装置文件就像这样简单：

[
{
    "model": "contenttypes.contenttype",
    "pk": 1,
    "fields": {
        "app_label": "admin",
        "model": "logentry"
    }
},
{
    "model": "contenttypes.contenttype",
    "pk": 2,
    "fields": {
        "app_label": "auth",
        "model": "permission"
    }
}]

当我跑时./manage.py loaddata initial_data.json，我得到：

django.db.utils.IntegrityError: Problem installing fixture '/home/user/reponame/projectname/initial_data.json': Could not load contenttypes.ContentType(pk=2): UNIQUE constraint failed: django_content_type.app_label, django_content_type.model

我做了什么，使其工作只是重新命名pk，以id对contenttypes.contenttype模型。之后，迁移按预期进行。

./manage.py loaddata initial_data.json 
Installed 2 object(s) from 1 fixture(s)

更改后，我的initial_data.json文件是：

[
{
    "model": "contenttypes.contenttype",
    "id": 1,
    "fields": {
        "app_label": "admin",
        "model": "logentry"
    }
},
{
    "model": "contenttypes.contenttype",
    "id": 2,
    "fields": {
        "app_label": "auth",
        "model": "permission"
    }
}]

值得一提的是，我原来的initial_dataj.json还有很多其他的模型，只是为了解决我的问题才把pk重命名为idcontenttypes.contenttype。

Answer 2

创建数据库转储时排除 ContentType 和 Auth Permissions 对象。

python manage.py dumpdata --natural-foreign --natural-primary -e contenttypes -e auth.Permission --indent 2 > dump.json

之后，您应该能够毫无问题地运行该命令

python manage.py loaddata dump.json

感谢 https://www.coderedcorp.com/blog/how-to-dump-your-django-database-and-load-it-into-/ 救了我的一天

Answer 3

我有一个类似的问题。灵感来自这篇文章：

https://github.com/yourlabs/django-cities-light/issues/89（参见“如何修复它”）

在运行 loaddata 命令之前，我在“保存功能”之前评论了接收器信号装饰器，并且它起作用了。