Python 如何在没有base.metadata的情况下使用sqlAlchemy删除表

我想使用db.Model删除一个特定的表，但我不知道如何删除。 我遵循Miguel Grinberg（）的tuto教程，它使用db.Model而不是doc（）显示的Base声明性Base。 我不知道什么是最好的解决办法

我使用蓝图，所以我在init.py中声明db

我在models.py中导入db

在我的代码中：

...
Label.__table__.drop()

我可以不使用Base从数据库中删除一个表吗？如果是，如何进行

如果不可能，如何以及在何处声明基、引擎等？（我不知道如何处理蓝图和创建应用程序（） 我在那里找到了解决办法[https://stackoverflow.com/questions/35918605/how-to-delete-a-table-in-sqlalchemy/35918731]它使用的是基本概念

标签。表格.drop（）

但要么它需要引擎，要么它在我执行建议的解决方案时不工作，要么

Label.__table___.drop(db)
...
Error : 
File "C:\Python38\Lib\site-packages\flask\app.py", line 2464, in __call__
File "C:\Python38\Lib\site-packages\flask\app.py", line 2450, in wsgi_app
File "C:\Python38\Lib\site-packages\flask\app.py", line 1867, in handle_exception
File "C:\Python38\Lib\site-packages\flask\_compat.py", line 39, in reraise
File "C:\Python38\Lib\site-packages\flask\app.py", line 2447, in wsgi_app
File "C:\Python38\Lib\site-packages\flask\app.py", line 1952, in full_dispatch_request
File "C:\Python38\Lib\site-packages\flask\app.py", line 1821, in handle_user_exception
File "C:\Python38\Lib\site-packages\flask\_compat.py", line 39, in reraise
File "C:\Python38\Lib\site-packages\flask\app.py", line 1950, in full_dispatch_request
File "C:\Python38\Lib\site-packages\flask\app.py", line 1936, in dispatch_request
File "C:\Users\Documents\code\MyApp\views.py", line 28, in foo
"C:\Python38\Lib\site-packages\sqlalchemy\sql\schema.py", line 884, in drop
AttributeError: 'SQLAlchemy' object has no attribute '_run_visitor'

我不做drop_all（），因为我的数据库中有更多的表 谢谢你的回答

...
Label.__table__.drop()

Label.__table___.drop(db)
...
Error : 
File "C:\Python38\Lib\site-packages\flask\app.py", line 2464, in __call__
File "C:\Python38\Lib\site-packages\flask\app.py", line 2450, in wsgi_app
File "C:\Python38\Lib\site-packages\flask\app.py", line 1867, in handle_exception
File "C:\Python38\Lib\site-packages\flask\_compat.py", line 39, in reraise
File "C:\Python38\Lib\site-packages\flask\app.py", line 2447, in wsgi_app
File "C:\Python38\Lib\site-packages\flask\app.py", line 1952, in full_dispatch_request
File "C:\Python38\Lib\site-packages\flask\app.py", line 1821, in handle_user_exception
File "C:\Python38\Lib\site-packages\flask\_compat.py", line 39, in reraise
File "C:\Python38\Lib\site-packages\flask\app.py", line 1950, in full_dispatch_request
File "C:\Python38\Lib\site-packages\flask\app.py", line 1936, in dispatch_request
File "C:\Users\Documents\code\MyApp\views.py", line 28, in foo
"C:\Python38\Lib\site-packages\sqlalchemy\sql\schema.py", line 884, in drop
AttributeError: 'SQLAlchemy' object has no attribute '_run_visitor'