Connection lost to MySQL Server during query

Question

I have got a problem in mysql: My PHP gets disconnected from MySQL for a simple query. The error is:

Lost connection to MySQL server during query.

And it is thrown from :

  $stmt->execute();

Here is my PHP code:

$app->post('/checkmd5', function() use($app) {
    $data = $app->request()->params();
    $version = $data["VERSION"];
    $md5 = $data["MD5"];

    $stmt = getDb()->prepare("SELECT MD5 FROM UpdateInfo WHERE VersionName = ?");
    $stmt->bind_param("s", $version);
    $stmt->execute();
    $stmt->store_result();
    if ($stmt->num_rows() > 0) {
        $stmt->bind_result($dbMD5);
        $stmt->fetch();
        if ($md5 == $dbMD5)
        {
            $app->render(200, array("SUCCESS_MD5_MATCH", "VALID" => "true"));
        }
        else
        {
            $app->render(400, array("msg" => "ERROR_NO_MD5_MATCH", "VALID" => "false"));
        }
    }
    else
    {

        $app->render(400, array("msg" => "ERROR_VERSION_STRING_NOT_FOUND", "VALID" => "false", "VERSION" => $version));
    }
});

In PHPMyAdmin it works:

And this is what PHP gives out:

Answer 1

只需将getDb（）的返回值保存到变量中即可解决该问题。