无法从数据库中提取 BLOB

Cannot extract BLOB from the database

我正在使用 wamp 服务器和 phpmyadmin 以及 php 来实现我的数据库应用程序。我在数据库中存储了 BLOB 文件。但是我无法以原始格式提取 blob 文件并允许用户以原始格式下载它。有人能帮帮我吗?附上我从数据库中提取blob时的格式截图。

还附上了从数据库中提取的代码。该代码正确提取了除 BLOBS 之外的所有内容。请有人帮助我。

foreach($_POST['passport'] as $entry) 
{
    $sql = "SELECT $entry FROM passport WHERE UID = '$j'";
    $a = mysqli_query($conn,$sql);
    $b = mysqli_fetch_array($a);
    $c = $b[0];
    echo "<tr><td>{$entry}</td><td>$c</td></tr>";
}

The screenshot of the image as I have mentioned in my comment

试试这个:

foreach ($_POST['passport'] as $entry) 
{
    $sql = "SELECT $entry FROM passport WHERE UID = '$j'";
    $a = mysqli_query($conn,$sql);
    $b = mysqli_fetch_array($a);
    $c = $b[0];
    echo '<tr><td><img src="data:image/jpeg;base64,' . base64_encode($entry) . '"></td><td>' . $c . '</td></tr>';
}