# SQL (Relational) Databases

**FastAPI** doesn't require you to use a SQL (relational) database. But you can use **any database** that you want.

Here we'll see an example using <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel</a>.

<div class="screenshot">
<img src="/img/tutorial/sql-databases/image01.png">
</div>

## Atualizar o App com Múltiplos Modelos

Agora vamos **refatorar** este app um pouco para aumentar a **segurança** e **versatilidade**.

---> 100%
```

</div>

## ✍ 🇸🇲 🍕

➡️ 🔗 📁 `sql_app/database.py`.

### 🗄 🇸🇲 🍕

```Python hl_lines="1-3"
{!../../docs_src/sql_databases/sql_app/database.py!}
```

### ✍ 💽 📛 🇸🇲

```Python hl_lines="5-6"
{!../../docs_src/sql_databases/sql_app/database.py!}
```

👉 🖼, 👥 "🔗" 🗄 💽 (📂 📁 ⏮️ 🗄 💽).

📁 🔜 🔎 🎏 📁 📁 `sql_app.db`.

---> 100%
```

</div>

## 创建 SQLAlchemy 部件

让我们转到文件`sql_app/database.py`。

### 导入 SQLAlchemy 部件

```Python hl_lines="1-3"
{!../../docs_src/sql_databases/sql_app/database.py!}
```

### 为 SQLAlchemy 定义数据库 URL地址

```Python hl_lines="5-6"
{!../../docs_src/sql_databases/sql_app/database.py!}
```

在这个例子中，我们正在“连接”到一个 SQLite 数据库（用 SQLite 数据库打开一个文件）。

# Testing a Database

You can study about databases, SQL, and SQLModel in the <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel docs</a>. 🤓

There's a mini <a href="https://sqlmodel.tiangolo.com/tutorial/fastapi/" class="external-link" target="_blank">tutorial on using SQLModel with FastAPI</a>. ✨

Dit betekent ook dat je in veel gevallen het object dat je van een request krijgt **direct naar je database** kunt sturen, omdat alles automatisch wordt gevalideerd.

Hetzelfde geldt ook andersom, in veel gevallen kun je dus het object dat je krijgt van de database **direct doorgeven aan de client**.

This also means that in many cases you can pass the same object you get from a request **directly to the database**, as everything is validated automatically.

The same applies the other way around, in many cases you can just pass the object you get from the database **directly to the client**.

    page = context.new_page()
    page.goto("http://localhost:8000/docs")
    page.get_by_label("post /heroes/").click()
    # Manually add the screenshot
    page.screenshot(path="docs/en/docs/img/tutorial/sql-databases/image02.png")

    # ---------------------
    context.close()
    browser.close()


process = subprocess.Popen(
    ["fastapi", "run", "docs_src/sql_databases/tutorial002.py"],
)
try:

    page = context.new_page()
    page.goto("http://localhost:8000/docs")
    page.get_by_label("post /heroes/").click()
    # Manually add the screenshot
    page.screenshot(path="docs/en/docs/img/tutorial/sql-databases/image01.png")

    # ---------------------
    context.close()
    browser.close()


process = subprocess.Popen(
    ["fastapi", "run", "docs_src/sql_databases/tutorial001.py"],
)
try:

You will see examples of this in the next chapters, about relational and NoSQL databases, security, etc.

## **FastAPI** compatibility

The simplicity of the dependency injection system makes **FastAPI** compatible with:

* all the relational databases
* NoSQL databases
* external packages
* external APIs
* authentication and authorization systems
* API usage monitoring systems