<?php
$host = "localhost";
$dbuser = "home_user";
$dbpass = "AZ*******l9";
$db = "data";
$charset = 'utf8';

$dsn = "mysql:host=$host;dbname=$db;charset=$charset";
$opt = [
           PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
           PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
           PDO::ATTR_EMULATE_PREPARES => false,
       ];
$pdo = new PDO($dsn, $dbuser, $dbpass, $opt);

$id = $_GET["id"];
$data = $_GET["data"];
$sql = "INSERT INTO `data_table` (`id`, `data`) VALUES ('".$id."', '".$data."');";
$send = $pdo->prepare($sql);
$send->execute();
echo("ok");
?>

print($send->errorInfo());

try{...} catch (PDOException $e)
{
    print($e);
}

<?php
ini_set('error_reporting', E_ALL);
ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);