//// tab | Python 3.10+

```Python hl_lines="17-19"
{!> ../../docs_src/body_multiple_params/tutorial001_py310.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="19-21"
{!> ../../docs_src/body_multiple_params/tutorial001.py!}
```

////

/// note | "Nota"

# Первые шаги

Самый простой FastAPI файл может выглядеть так:

```Python
{!../../docs_src/first_steps/tutorial001.py!}
```

Скопируйте в файл `main.py`.

Запустите сервер в режиме реального времени:

<div class="termy">

```console
$ uvicorn main:app --reload

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)

Pour cela, importez d'abord `Query` depuis `fastapi` :

{* ../../docs_src/query_params_str_validations/tutorial002.py hl[3] *}

## Utiliser `Query` comme valeur par défaut

Construisez ensuite la valeur par défaut de votre paramètre avec `Query`, en choisissant 50 comme `max_length` :

{* ../../docs_src/query_params_str_validations/tutorial002.py hl[9] *}

Por exemplo, você pode adicionar um arquivo `config.py` com:

```Python
{!../../docs_src/settings/app01/config.py!}
```

E utilizar essa configuração em `main.py`:

```Python hl_lines="3  11-13"
{!../../docs_src/settings/app01/main.py!}
```

/// dica

在文档中也有一篇使用 Peewee 的等效的文章。

///

## 文件结构

对于这些示例，假设您有一个名为的目录`my_super_project`，其中包含一个名为的子目录`sql_app`，其结构如下：

```
.
└── sql_app
    ├── __init__.py
    ├── crud.py
    ├── database.py
    ├── main.py
    ├── models.py
    └── schemas.py
```

该文件`__init__.py`只是一个空文件，但它告诉 Python `sql_app` 是一个包。

现在让我们看看每个文件/模块的作用。

## 安装 SQLAlchemy

首先你需要安装`SQLAlchemy`:

<div class="termy">

```console

```Python hl_lines="4"
{!> ../../docs_src/body_fields/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="4"
{!> ../../docs_src/body_fields/tutorial001_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="4"
{!> ../../docs_src/body_fields/tutorial001_an.py!}
```

////

//// tab | Python 3.10+ non-Annotated

/// tip

```Python hl_lines="2-4"
{!../../docs_src/dependencies/tutorial007.py!}
```

O valor gerado (yielded) é o que é injetado nas *operações de rota* e outras dependências.

```Python hl_lines="4"
{!../../docs_src/dependencies/tutorial007.py!}
```

O código após o `yield` é executado após a resposta ser entregue:

```Python hl_lines="5-6"
{!../../docs_src/dependencies/tutorial007.py!}
```

/// tip | "Dica"

```Python hl_lines="28-33"
{!> ../../../docs_src/body_updates/tutorial001_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="30-35"
{!> ../../../docs_src/body_updates/tutorial001_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="30-35"
{!> ../../../docs_src/body_updates/tutorial001.py!}
```

////

```Python hl_lines="28-33"
{!> ../../docs_src/body_updates/tutorial001_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="30-35"
{!> ../../docs_src/body_updates/tutorial001_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="30-35"
{!> ../../docs_src/body_updates/tutorial001.py!}
```

////

`PUT` is used to receive data that should replace the existing data.

```Python hl_lines="1"
{!> ../../docs_src/python_types/tutorial009_py310.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="1  4"
{!> ../../docs_src/python_types/tutorial009.py!}
```

////

//// tab | Python 3.8+ Alternative

```Python hl_lines="1  4"
{!> ../../docs_src/python_types/tutorial009b.py!}
```

////

#### `Union` oder `Optional` verwenden?