$objectManager = MagentoFrameworkAppObjectManager::getInstance();
$resource = $objectManager->get('MagentoFrameworkAppResourceConnection');
$connection = $resource->getConnection();

$sqlx = "SELECT * FROM sales_order ORDER BY entity_id DESC LIMIT 1";
$connection->query($sqlx);
$resultx = $connection->fetchAll($sqlx);
foreach($resultx as $resulx)
{
    $entityid  = $resulx['entity_id'];
}

$sql = "SELECT * FROM sales_order_item WHERE order_id='$entityid'";
$connection->query($sql);
$results = $connection->fetchAll($sql);

foreach($results as $result)
{
    $item_id = $result['item_id'];

    /* DO WHATEVER YOU WANT HERE */

    $upsql = "UPDATE sales_order_item SET product_options='$finalque' WHERE item_id='$item_id'";
    $connection->query($upsql);
    }
}