Django 1.8：为现有架构创建初始迁移 [英] Django 1.8: Create initial migrations for existing schema

问题描述

我开始了一个django 1.8项目，它使用迁移系统。

不知何故，事情变得凌乱，所以我从DB中删除了迁移文件夹和表，现在我试图重建它们，没有成功。

I started a django 1.8 project, which uses the migrations system.
Somehow along the way things got messy, so I erased the migrations folders and table from the DB, and now I'm trying to reconstruct them, with no success.

我有三个应用程序（3 models.py 文件），模型反映表格！

I have three apps (3 models.py files), and the models reflect the tables EXACTLY!

目前我发现的最佳方法是：

The best approach that I've found so far was:

1. 擦除所有迁移文件夹。完成！


2. 从 django_migrations 表中删除所有内容。完成！


3. 为每个应用程序运行 python manage.py makemigrations --empty< app> 完成！


4. 运行 python manage.py migrate --fake 。完成！ （虽然它只有在每个 makemigrations 命令之后运行时才起作用。

1. Erase all migrations folders. Done!
2. Delete everything from the django_migrations table. Done!
3. Run python manage.py makemigrations --empty <app> for every app. Done!
4. Run python manage.py migrate --fake. Done! (although it works only if I run it after every makemigrations command.

现在我添加一个新的字段，运行 makemigrations 命令，我收到以下错误：

django.db.utils .OperationalError：（1054，'未知列'accounts_plan.max_item_size'in'field list'）

Now I add a new field, run the makemigrations command, and I receive the following error:
django.db.utils.OperationalError: (1054, "Unknown column 'accounts_plan.max_item_size' in 'field list'")

我一直在燃烧HOURS这个东西，我可以如何初始化迁移，以便每次都可以继续工作，而不会有迁移中断？

I've been burning HOURS on this thing. How the h**l can I initialize the migrations so I can continue working without migration interruptions every time?

为什么这么复杂？有一个简单的单行： initiate_migrations_from_schema ？

Why is it so complicated? Why isn't there a simple one-liner: initiate_migrations_from_schema?

编辑：

现在事情变得平衡nastier，我截断了 django_migrations 表，并删除了所有的迁移文件夹。

现在我尝试运行 python manage.py migrate --fake-initial （我在DEV文档中找到的东西），只需设置Django的所有内部应用程序（auth，session等），我得到：

（1054，'django_content_type'中的未知列'名称）。 br>
现在，这个列不是一个真正的列。在Django的 contenttypes 应用程序中定义了一个 @property 。这里发生了什么？为什么将名称属性识别为真正的列？

Now things get even nastier. I truncated the django_migrations table and deleted all the migrations folder.
Now I try to run python manage.py migrate --fake-initial (something I found in the DEV docs), just so it sets up all of Django's 'internal' apps (auth, session, etc) and I'm getting:
(1054, "Unknown column 'name' in 'django_content_type'").
Now, this "column" is not a real column. It's a @property defined in Django's contenttypes app. WHAT IS GOING ON HERE? Why is it identifying the name property as a real column?

推荐答案

最终让它工作，虽然我不知道为什么，我希望它将来会有效。

经过多次试验，并通过Django的开发网站（链接）。

这是步骤（对于遇到这个问题的人）：

Finally got it to work, although I don't know why and I hope it will work in the future.
After doing numerous trials and going through Django's dev site (link).
Here are the steps (for whoever runs into this problem):

1. 清空 django_migrations 表： code>从django_migrations删除;


2. 对于每个应用程序，删除其迁移文件夹： code> rm -rf< app> / migrations /


3. 重置内置应用的迁移： python manage.py migrate --fake


4. 对于每个运行的应用程序： python manage.py makemigrations< app> 。最后： python manage.py migrate --fake-initial



1. Empty the django_migrations table: delete from django_migrations;
2. For every app, delete its migrations folder: rm -rf <app>/migrations/
3. Reset the migrations for the "built-in" apps: python manage.py migrate --fake
4. For each app run: python manage.py makemigrations <app>. Take care of dependencies (models with ForeignKey's should run after their parent model).
5. Finally: python manage.py migrate --fake-initial

之后，我运行了最后一个命令，没有 - fake-initial 标志，只是为了确保。

After that I ran the last command without the --fake-initial flag, just to make sure.

现在一切正常，我可以正常使用迁移系统。

Now everything works and I can use the migrations system normally.

我相信我不是唯一遇到这个问题的人。必须记录更好，甚至简化。

I'm sure I'm not the only one who encounters this issue. It must be documented better and even simplified.

Django 1.9用户更新：

我再次遇到这种情况一个Django 1.9.4和第5步失败了。

我所要做的就是用替换 - 假 - 初始 - fake 使其正常工作。

Update for Django 1.9 users:
I had this scenario again with a Django 1.9.4, and step 5 failed.
All I had to do is replace --fake-initial with --fake to make it work.

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