Django 使用现有数据库时无法运行迁移
我正在使用最新版本的Django 3和Python3来学习Django 我想为我的django项目使用现有的sqlite3数据库。但是我在使用migrate命令时遇到了问题 到目前为止,我对我的项目只做了几步: 1.使用venv,升级pip,安装django 2.生成一个项目 3.插入一个应用程序,并将其添加到Django 使用现有数据库时无法运行迁移,django,Django,我正在使用最新版本的Django 3和Python3来学习Django 我想为我的django项目使用现有的sqlite3数据库。但是我在使用migrate命令时遇到了问题 到目前为止,我对我的项目只做了几步: 1.使用venv,升级pip,安装django 2.生成一个项目 3.插入一个应用程序,并将其添加到已安装的应用程序中 4.在settings.py中,我将现有数据库添加到数据库中,如下所示 DATABASES = { 'default': { 'ENGINE':
已安装的应用程序中
4.在settings.py
中,我将现有数据库添加到数据库中,如下所示
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
},
'testdb': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'TestDB.sqlite3'),
},
}
然后我使用如下所示的方法生成models.py文件。
生成的models.py
如下所示:(其中我添加了max_length=25
)
6.然后运行python manage.py migrate
和/或python manage.py makemigrations
,在这里我看到以下错误:
(venv) PS D:\Workfolder_Web\testProject\backend\project> python .\manage.py migrate
Traceback (most recent call last):
File ".\manage.py", line 21, in <module>
main()
File ".\manage.py", line 17, in main
execute_from_command_line(sys.argv)
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\core\management\__init__.py", line 401, in execute_from_command_line
utility.execute()
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\core\management\__init__.py", line 377, in execute
django.setup()
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\__init__.py", line 24, in setup
apps.populate(settings.INSTALLED_APPS)
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\apps\registry.py", line 114, in populate
app_config.import_models()
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\apps\config.py", line 211, in import_models
self.models_module = import_module(models_module_name)
File "C:\Users\Administrator\AppData\Local\Programs\Python\Python38-32\lib\importlib\__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
File "<frozen importlib._bootstrap>", line 991, in _find_and_load
File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 779, in exec_module
File "<frozen importlib._bootstrap_external>", line 916, in get_code
File "<frozen importlib._bootstrap_external>", line 846, in source_to_code
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
ValueError: source code string cannot contain null bytes
(venv)PS D:\Workfolder\u Web\testProject\backend\project>python。\manage.py迁移
回溯(最近一次呼叫最后一次):
文件“\manage.py”,第21行,在
main()
文件“\manage.py”,主菜单第17行
从命令行(sys.argv)执行命令
文件“D:\Workfolder\u Web\testProject\backend\venv\lib\site packages\django\core\management\\uuuuuu init\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu
utility.execute()
文件“D:\Workfolder\u Web\testProject\backend\venv\lib\site packages\django\core\management\\uuuuuuu init\uuuuuu.py”,第377行,在execute中
django.setup()
文件“D:\Workfolder\u Web\testProject\backend\venv\lib\site packages\django\\uuuuuu init\uuuuu.py”,第24行,在安装程序中
应用程序。填充(设置。已安装的应用程序)
文件“D:\Workfolder\u Web\testProject\backend\venv\lib\site packages\django\apps\registry.py”,第114行,在“填充”中
app_config.import_models()
文件“D:\Workfolder\u Web\testProject\backend\venv\lib\site packages\django\apps\config.py”,第211行,在导入模型中
self.models\u module=导入模块(models\u module\u name)
文件“C:\Users\Administrator\AppData\Local\Programs\Python\Python38-32\lib\importlib\\uuuuuuu init\uuuuuu.py”,第127行,在导入模块中
return _bootstrap._gcd_import(名称[级别:],包,级别)
文件“”,第1014行,在\u gcd\u导入中
文件“”,第991行,在“查找”和“加载”中
文件“”,第975行,在“查找”和“加载”中解锁
文件“”,第671行,在\u加载\u解锁
exec_模块中第779行的文件“”
文件“”,第916行,get_代码
文件“”,第846行,源代码为
文件“”,第219行,在“调用”中,删除了“帧”
ValueError:源代码字符串不能包含空字节
7.我的数据库TestDB.sqlite3
非常简单,它看起来像:
问题:我如何调试它?我在当前代码中没有使用任何引导、URL、视图或路由器
谢谢你的帮助 如果更改了模型,则为新字段添加默认值或删除数据库。如果更改了模型,则为新字段添加默认值或删除数据库
(venv) PS D:\Workfolder_Web\testProject\backend\project> python .\manage.py migrate
Traceback (most recent call last):
File ".\manage.py", line 21, in <module>
main()
File ".\manage.py", line 17, in main
execute_from_command_line(sys.argv)
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\core\management\__init__.py", line 401, in execute_from_command_line
utility.execute()
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\core\management\__init__.py", line 377, in execute
django.setup()
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\__init__.py", line 24, in setup
apps.populate(settings.INSTALLED_APPS)
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\apps\registry.py", line 114, in populate
app_config.import_models()
File "D:\Workfolder_Web\testProject\backend\venv\lib\site-packages\django\apps\config.py", line 211, in import_models
self.models_module = import_module(models_module_name)
File "C:\Users\Administrator\AppData\Local\Programs\Python\Python38-32\lib\importlib\__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
File "<frozen importlib._bootstrap>", line 991, in _find_and_load
File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 779, in exec_module
File "<frozen importlib._bootstrap_external>", line 916, in get_code
File "<frozen importlib._bootstrap_external>", line 846, in source_to_code
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
ValueError: source code string cannot contain null bytes