So, they will be included in the JSON response.

!!! tip
    Notice that the default values can be anything, not only `None`.

    They can be a list (`[]`), a `float` of `10.5`, etc.

### `response_model_include` and `response_model_exclude`

You can also use the *path operation decorator* parameters `response_model_include` and `response_model_exclude`.

    options:
        members:
            - openapi_version
            - webhooks
            - state
            - dependency_overrides
            - openapi
            - websocket
            - include_router
            - get
            - put
            - post
            - delete
            - options
            - head
            - patch
            - trace
            - on_event

### `response_model_include` 和 `response_model_exclude`

你还可以使用*路径操作装饰器*的 `response_model_include` 和 `response_model_exclude` 参数。

它们接收一个由属性名称 `str` 组成的 `set` 来包含（忽略其他的）或者排除（包含其他的）这些属性。

如果你只有一个 Pydantic 模型，并且想要从输出中移除一些数据，则可以使用这种快捷方法。

!!! tip
    但是依然建议你使用上面提到的主意，使用多个类而不是这些参数。

    这是因为即使使用 `response_model_include` 或 `response_model_exclude` 来省略某些属性，在应用程序的 OpenAPI 定义（和文档）中生成的 JSON Schema 仍将是完整的模型。

!!! info "情報"
    以下も使用することができます:

    * `response_model_exclude_defaults=True`
    * `response_model_exclude_none=True`

## Include an `APIRouter` in another

The same way you can include an `APIRouter` in a `FastAPI` application, you can include an `APIRouter` in another `APIRouter` using:

```Python
router.include_router(other_router)
```

This is different from using an `APIRouter` as a mounted application is completely independent. The OpenAPI and docs from your main application won't include anything from the mounted application, etc.

You can read more about this in the [Advanced User Guide](../advanced/index.md){.internal-link target=_blank}.

## Details

### Disable automatic server from `root_path`

If you don't want **FastAPI** to include an automatic server using the `root_path`, you can use the parameter `root_path_in_servers=False`:

```Python hl_lines="9"
{!../../../docs_src/behind_a_proxy/tutorial004.py!}
```

and then it won't include it in the OpenAPI schema.

## Mounting a sub-application

    FastAPI will use the `response_model` parameter (that includes dataclasses) to convert the response.

You can combine `dataclasses` with other type annotations in many different combinations to form complex data structures.

Check the in-code annotation tips above to see more specific details.

## Learn More

You can also combine `dataclasses` with other Pydantic models, inherit from them, include them in your own models, etc.

* **Uvicorn**:
    * Will have the best performance, as it doesn't have much extra code apart from the server itself.
    * You wouldn't write an application in Uvicorn directly. That would mean that your code would have to include more or less, at least, all the code provided by Starlette (or **FastAPI**). And if you did that, your final application would have the same overhead as having used a framework and minimizing your app code and bugs.

# Testing a Database

!!! info
    These docs are about to be updated. 🎉

    The current version assumes Pydantic v1, and SQLAlchemy versions less than 2.0.

    The new docs will include Pydantic v2 and will use <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel</a> (which is also based on SQLAlchemy) once it is updated to use Pydantic v2 as well.