<span style="background-color:#C4A000"><font color="#2E3436">╰─────────────────────────────────────────────────────╯</font></span>

<font color="#4E9A06">INFO</font>:     Will watch for changes in these directories: [&apos;/home/user/code/awesomeapp&apos;]
<font color="#4E9A06">INFO</font>:     Uvicorn running on <b>http://127.0.0.1:8000</b> (Press CTRL+C to quit)

```

因为上述数据未包含已存储的属性 `"tax": 20.2`，新的输入模型会把 `"tax": 10.5` 作为默认值。

因此，本次操作把 `tax` 的值「更新」为 `10.5`。

## 用 `PATCH` 进行部分更新

<a href="https://developer.mozilla.org/zh-CN/docs/Web/HTTP/Methods/PATCH" class="external-link" target="_blank">HTTP `PATCH`</a> 操作用于更新 *部分* 数据。

即，只发送要更新的数据，其余数据保持不变。

!!! note "笔记"

    `PATCH` 没有 `PUT` 知名，也怎么不常用。

    很多人甚至只用 `PUT` 实现部分更新。

    **FastAPI** 对此没有任何限制，可以**随意**互换使用这两种操作。

        {
            "detail": [
                {
                    "type": "string_pattern_mismatch",
                    "loc": ["query", "item-query"],
                    "msg": "String should match pattern '^fixedquery$'",
                    "input": "nonregexquery",
                    "ctx": {"pattern": "^fixedquery$"},
                }
            ]
        }
    ) | IsDict(

des changements non rétrocompatibles.

FastAPI suit également la convention que tout changement de version "PATCH" est pour des corrections de bogues et
des changements rétrocompatibles.

!!! tip "Astuce"
    Le "PATCH" est le dernier chiffre, par exemple, dans `0.2.3`, la version PATCH est `3`.

Donc, vous devriez être capable d'épingler une version comme suit :

```txt
fastapi>=0.45.0,<0.46.0
```

            - openapi
            - websocket
            - include_router
            - get
            - put
            - post
            - delete
            - options
            - head
            - patch
            - trace
            - on_event
            - middleware

async def read_items(
    q: Union[str, None] = Query(
        default=None,
        alias="item-query",
        title="Query string",
        description="Query string for the items to search in the database that have a good match",
        min_length=3,
        max_length=50,
        pattern="^fixedquery$",
        deprecated=True,
    ),
):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:

          }
        }
      }
    }

    await fs.promises.writeFile(
      filePath,
      JSON.stringify(openapiContent, null, 2),
    )
    console.log('File successfully modified')
  } catch (err) {
    console.error('Error:', err)
  }
}

const filePath = './openapi.json'

def test_get_portal():
    response = client.get("/teleport", follow_redirects=False)
    assert response.status_code == 307, response.text
    assert response.headers["location"] == "https://www.youtube.com/watch?v=dQw4w9WgXcQ"


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "openapi": "3.1.0",

def test_get_redirect():
    response = client.get("/portal", params={"teleport": True}, follow_redirects=False)
    assert response.status_code == 307, response.text
    assert response.headers["location"] == "https://www.youtube.com/watch?v=dQw4w9WgXcQ"


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "openapi": "3.1.0",

```Python hl_lines="6  11"
{!../../../docs_src/path_params/tutorial003.py!}
```

Otherwise, the path for `/users/{user_id}` would match also for `/users/me`, "thinking" that it's receiving a parameter `user_id` with a value of `"me"`.

Similarly, you cannot redefine a path operation:

```Python hl_lines="6  11"