$link = mysqli_connect("localhost","root","root","dbname"); // 连接数据库
$sql = "select field from dbname limit 1";
$ressql = mysqli_query($link,$sql);// 执行 sql
$res = $ressql->fetch_object()->field;// 得到结果
来源: http://www.bubuko.com/infodetail-2460052.html