<?php
$hostname = "localhost";
$username = "유저이름";
$password = "비밀번호";
$database = "DB이름";

$conn = new mysqli($hostname, $username, $password, $database);
$conn->set_charset("utf-8"); //한글깨짐 방지

if ($conn->connect_error) { //연결성공여부 확인
    die("Connection failed: " . $conn->connect_error);
}

//DB연결후 사용 예시
$result = mysqli_query($conn, "SELECT * FROM member");
while($row = mysqli_fetch_array($result)){
    echo $row['id'] . "<br/>";
}
?>