│                          │
 ╰──────────────────────────╯

<font color="#3465A4">INFO    </font> Using import string <font color="#8AE234"><b>main:app</b></font>

 <span style="background-color:#C4A000"><font color="#2E3436">╭────────── FastAPI CLI - Development mode ───────────╮</font></span>

```Python hl_lines="2-5  15  21"
{!../../../docs_src/handling_errors/tutorial006.py!}
```

## Docs

First, make sure you set up your environment as described above, that will install all the requirements.

### Docs live

During local development, there is a script that builds the site and checks for any changes, live-reloading:

<div class="termy">

```console
$ python ./scripts/docs.py live

这个`__tablename__`属性是用来告诉 SQLAlchemy 要在数据库中为每个模型使用的数据库表的名称。

### 创建模型属性/列

现在创建所有模型（类）属性。

这些属性中的每一个都代表其相应数据库表中的一列。

我们使用`Column`来表示 SQLAlchemy 中的默认值。

我们传递一个 SQLAlchemy “类型”，如`Integer`、`String`和`Boolean`，它定义了数据库中的类型，作为参数。

```Python hl_lines="1  10-13  21-24"
{!../../../docs_src/sql_databases/sql_app/models.py!}
```

### 创建关系

现在创建关系。

为此，我们使用SQLAlchemy  ORM提供的`relationship`。

デフォルトの例外ハンドラを`fastapi.exception_handlers`からインポートして再利用することができます:

```Python hl_lines="2 3 4 5 15 21"
{!../../../docs_src/handling_errors/tutorial006.py!}
```

この例では、非常に表現力のあるメッセージでエラーを`print`しています。

                            "items": {
                                "anyOf": [{"type": "string"}, {"type": "integer"}]
                            },
                        },
                        "msg": {"title": "Message", "type": "string"},
                        "type": {"title": "Error Type", "type": "string"},
                    },
                },
                "HTTPValidationError": {

                    "properties": {
                        "username": {"title": "Username", "type": "string"},
                        "password": {"title": "Password", "type": "string"},
                        "email": {
                            "title": "Email",
                            "type": "string",
                            "format": "email",
                        },

                            "pattern": "password",
                            "type": "string",
                        },
                        "username": {"title": "Username", "type": "string"},
                        "password": {"title": "Password", "type": "string"},
                        "scope": {"title": "Scope", "type": "string", "default": ""},
                        "client_id": IsDict(
                            {

                                "type": "string",
                            }
                        ),
                        "username": {"title": "Username", "type": "string"},
                        "password": {"title": "Password", "type": "string"},
                        "scope": {"title": "Scope", "type": "string", "default": ""},
                        "client_id": IsDict(

                            "items": {
                                "anyOf": [{"type": "string"}, {"type": "integer"}]
                            },
                        },
                        "msg": {"title": "Message", "type": "string"},
                        "type": {"title": "Error Type", "type": "string"},
                    },
                },
                "HTTPValidationError": {