KeyError: u"Migration rango.0002_auto_20150905_0345 依赖项引用不存在的父节点

Question

我是 django 的新手，开始搞砸一些事情，看看会发生什么。问题是我现在有点搞砸了，希望能得到帮助。

我手动删除了一些迁移，然后运行

manage.py squashmigrations app migration_name

并更改了一些迁移，然后再次运行该命令。 问题是我现在正面临这个小错误。上次迁移引用另一个作为父级，但它现在不存在。

(kali)maker@localhost:~/Poker/tango_with_django_project$ sudo python manage.py migrate       
Traceback (most recent call last):
  File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 385, in execute_from_command_line
utility.execute()
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 377, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
 File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 288, in run_from_argv
self.execute(*args, **options.__dict__)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 338, in execute
output = self.handle(*args, **options)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/commands/migrate.py", line 63, in handle
executor = MigrationExecutor(connection, self.migration_progress_callback)
  File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/executor.py", line 17, in __init__
self.loader = MigrationLoader(self.connection)
  File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/loader.py", line 48, in __init__
self.build_graph()
  File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/loader.py", line 237, in build_graph
self.graph.add_dependency(migration, key, parent)
  File "/usr/local/lib/python2.7/dist-packages/django/db/migrations/graph.py", line 46, in add_dependency
"Migration %s dependencies reference nonexistent parent node %r" % (migration, parent)
KeyError: u"Migration rango.0002_auto_20150905_0345 dependencies reference nonexistent parent node (u'rango', u'0001_squashed_0004_auto_20150904_2325')"

Answer 1

就我而言，

1. 删除数据库（请备份/导出数据）
2. 删除 migrate 文件夹中的 *.pyc 文件
3. 删除 migrate 文件夹中的迁移文件，除了 init.py
4. 创建具有相同名称的新数据库
5. 为用户 db 授予权限
6. 迁移
7. 迁移
8. 创建超级用户
9. 运行服务器

最后，它起作用了。