更新仅发生在第一个数据库中，而不发生在第二个数据库中

When we try to update, all the outputs ("Successful step") 1,2,4,5 are shown. But when we try to check the database, only the 1st database was able to do the update.

$host = "172.16.1.16";
$user  = "root";
$password =  "root";
$dbname1 = "nocs";
$dbname2 = "nocs_backup";

Here is the first database

$db1 = new mysqli($host, $user, $password, $dbname1);
if($db1->connect_errno > 0){
    die('Unable to connect to database' . $db1->connect_error);
}
else
{
    $updateComponentSql = "UPDATE component 
                           SET `Component_name`='$name', `Brand`='$brand', 
                               `Model`='$model', `Type`='$type',
                               `Capacity`='$capacity',`Serial_no`='$serial', 
                               `Description`='Installed' 
                           WHERE `Component_id`='$d_id' 
                           AND `computer_id`='$c_id'";

    if (mysqli_query($db1, $updateComponentSql))
    {
        echo "<script type='text/javascript'>
                alert('Succesful step 1');
              </script>";   
    }

Here is the second

    $db2 = mysqli_connect($host, $user, $password, $dbname2);
    echo "<script type='text/javascript'>alert('Succesful step 2');</script>";

    if($db2->connect_errno > 0)
    {   
        die('Unable to connect to database' . $db2->connect_error);
        echo "<script type='text/javascript'>alert('Successful step 3');</script>";
    }
    else
    {
        echo "<script type='text/javascript'>alert('Succesful step 4');</script>";
            if (mysqli_query($db2, "UPDATE component 
                                    SET (`Component_name`='$name', 
                                         `Brand`='$brand', `Model`='$model', 
                                         `Type`='$type',`Capacity`='$capacity',
                                         `Serial_no`='$serial', 
                                         `Description`='Installed' 
                                     WHERE `Component_id`='$d_id' 
                                     AND `computer_id`='$c_id)" ))
            {
                echo "<script type='text/javascript'>
                        alert('Succesful step 5');
                      </script>";
            }   
        }

}

We're at our wit's end. Please help us :(

You have extraneous parentheses in the second UPDATE query.

if (mysqli_query($db2, "UPDATE component 
                        SET `Component_name`='$name', `Brand`='$brand', `Model`='$model', 
                            `Type`='$type', `Capacity`='$capacity', `Serial_no`='$serial', 
                            `Description`='Installed' 
                        WHERE `Component_id`='$d_id' AND `computer_id`='$c_id" ))
{
    echo "<script type='text/javascript'>alert('Succesful step 5');</script>";
} else {
    echo "<script type='text/javascript'>alert(" . json_encode(mysqli_error($db2)) . ");</script>";
}