What common mistakes can occur when including PHP files in a table layout like the one shown in the code snippet?

One common mistake when including PHP files in a table layout is not properly closing the PHP tags within the included file. This can lead to syntax errors or unexpected outputs in the table layout. To solve this, ensure that the PHP tags are correctly opened and closed within the included file.

<!-- Incorrect way of including PHP file in a table layout -->
<table>
    <tr>
        <td>
            <?php include 'file.php'; ?>
        </td>
    </tr>
</table>
```

```php
<!-- Correct way of including PHP file in a table layout -->
<table>
    <tr>
        <td>
            <?php include 'file.php'; ?>
        </td>
    </tr>
</table>