SQL查询今日的信息方法

$time_0 = strtotime(date('Y-m-d 00:00:00', time()));
$time_1 = strtotime(date('Y-m-d 23:59:59', time()));
$jinrishouru1 = mysqli_query($magcon,"SELECT sum(amount) as amount FROM mag_order WHERE paystate=3 AND paytime between $time_0 and $time_1");
$jinrishouru2 = mysqli_fetch_array($jinrishouru1);