{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[40:45] hl[40:45] *}

</details>

Here we use the `SessionDep` dependency (a `Session`) to add the new `Hero` to the `Session` instance, commit the changes to the database, refresh the data in the `hero`, and then return it.

### Read Heroes

We can **read** `Hero`s from the database using a `select()`. We can include a `limit` and `offset` to paginate the results.

		t.Fatalf("No error should raise, but got %v", err)
	}

	if err = tx2.First(&User{}, "name = ?", "transaction-2").Error; err != nil {
		t.Fatalf("Should find saved record, but got %v", err)
	}

	tx2.Commit()

	if err = db.First(&User{}, "name = ?", "transaction-2").Error; err != nil {
		t.Fatalf("Should be able to find committed record, but got %v", err)
	}

}

// Use a Scanner with a custom split function to parse a comma-separated
// list with an empty final value.
func ExampleScanner_emptyFinalToken() {
	// Comma-separated list; last entry is empty.
	const input = "1,2,3,4,"
	scanner := bufio.NewScanner(strings.NewReader(input))
	// Define a split function that separates on commas.
	onComma := func(data []byte, atEOF bool) (advance int, token []byte, err error) {

			"B",
		),
		"THIS.\n",
	},
	{
		"nested #define with args",
		lines(
			"#define A #define B(x) x",
			"A",
			"B(THIS)",
		),
		"THIS.\n",
	},
	/* This one fails. See comment in Slice.Col.
	{
		"nested #define with args",
		lines(
			"#define A #define B (x) x",
			"A",
			"B(THIS)",
		),
		"x.\n",
	},
	*/
}

func TestLex(t *testing.T) {

    * Suivez-moi pour voir quand je crée un nouveau projet Open Source.
* <a href="https://twitter.com/tiangolo" class="external-link" target="_blank">Me suivre sur **Twitter**</a>.
    * Dites-moi comment vous utilisez FastAPI (j'adore entendre ça).
    * Entendre quand je fais des annonces ou que je lance de nouveaux outils.

## Paramètres optionnels

De la même façon, vous pouvez définir des paramètres de requête comme optionnels, en leur donnant comme valeur par défaut `None` :

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

Ici, le paramètre `q` sera optionnel, et aura `None` comme valeur par défaut.

/// check | "Remarque"

This means that you can send only the data that you want to update, leaving the rest intact.

/// note

`PATCH` is less commonly used and known than `PUT`.

And many teams use only `PUT`, even for partial updates.

You are **free** to use them however you want, **FastAPI** doesn't impose any restrictions.

import java.util.Locale;
import java.util.Map;
import java.util.concurrent.TimeUnit;
import java.util.regex.Pattern;

import javax.net.ssl.SSLContext;

import org.apache.commons.io.output.DeferredFileOutputStream;
import org.apache.commons.lang3.SystemUtils;
import org.apache.http.Header;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;

<div class="termy">

```console
$ Get-Command python

C:\Users\user\code\awesome-project\.venv\Scripts\python
```

</div>

////

Isso significa que o programa `python` que será usado é aquele **no ambiente virtual**.

você usa `which` no Linux e macOS e `Get-Command` no Windows PowerShell.

<div class="termy">

```console
$ which pip

some/directory/fastapi/env/bin/pip
```

</div>

////

//// tab | Windows PowerShell

<div class="termy">

```console
$ Get-Command pip

some/directory/fastapi/env/bin/pip
```

</div>

////

Если в терминале появится ответ, что бинарник `pip` расположен по пути `.../env/bin/pip`, значит всё в порядке. 🎉