<?php

define('DB_HOST', "db");
define("DB_PORT", "3306");
define('DB_USER', "user");
define('DB_PASSWORD', "password");
define('DB_NAME', "trainee_db");

define('DSN', "mysql:host=" . DB_HOST . ";port=" . DB_PORT . ";dbname=" . DB_NAME . ";charset=utf8mb4");

$dbh = new PDO(DSN, DB_USER, DB_PASSWORD);

// エラーが発生した場合に例外をスローする設定
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$rows = $dbh->query("SELECT NOW() AS current_datetime")->fetchAll(PDO::FETCH_ASSOC);

foreach ($rows as $row) {
    echo "Current Date and Time: " . $row['current_datetime'] . "\n";
}

// MySQL接続を閉じる
$dbh = null;