<?php
$host = 'localhost';
$user_name = 'sunlight';
$password = 'sunlight';
$database_name = 'sunlight_db';
$port = 3306;

// データベースへ接続
$mysqli = @new mysqli( $host, $user_name, $password, $database_name, $port );

// 接続エラーの確認
if( $mysqli->connect_errno )
{
    die($mysqli->connect_errno . ' : ' . $mysqli->connect_error);
}

echo "Connected successfully : {$host}/{$database_name}";

// 接続解除
$mysqli->close();