laravel中处理时间，把时间拆分成天、小时（注：小时展示时要/24）

$day_diff = DB::raw(“timestampdiff(day, now(), completed_at) as diff_day”);

$hour_diff = DB::raw(“timestampdiff(hour, now(), completed_at) as diff_hour”);

$query=Demand::first([$day_diff,$hour_diff ]);
//运行结果
“data”: {
“diff_day”: 29,
“diff_hour”: 714
}