> For the complete documentation index, see [llms.txt](https://yeasy.gitbook.io/openstack_code_neutron/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://yeasy.gitbook.io/openstack_code_neutron/neutron/db/model_basepy.md).

# model\_base.py

定义了继承自 oslo.db.sqlalchemy.models.ModelBase的NeutronBase 和继承自其的 NeutronBaseV2 类。

![](/files/-M5y0ZUrKaw9PvPORyr_)

实际上，oslo.db.sqlalchemy.models.ModelBase是sqlalchemy的模型基础类，因此继承自其的类自动完成映射，可以对数据库进行操作。

最后，还定义了BASEV2作为其他地方可以继承的模型类。

```
BASEV2 = declarative.declarative_base(cls=NeutronBaseV2)
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://yeasy.gitbook.io/openstack_code_neutron/neutron/db/model_basepy.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.