Laravel where date / Carbon 相關操作

->whereYear('datetime', 2021)

->whereMonth('datetime', 7)

->whereDate('datetime', '<=', (new Carbon("2021-7"))->subMonth(1))

$today = Carbon::today();
$today->subMonth(6)  //這時$today=2021/03/24

->whereDate('create_datetime', '>=', $today->toImmutable()->subMonth(6))
->whereDate('create_datetime', '>=', $today->toImmutable()->subMonth(1))

->whereBetween('data_create_datetime', 
[(new Carbon($start_date))->startOfDay(), 
(new Carbon($end_date))->endOfDay()]);

$start_date = 2021/10/13
$end_date = 2021/10/20
(new Carbon($start_date))->startOfDay()   // => 2021/10/13 00:00:00
(new Carbon($end_date))->endOfDay()      // => 2021/10/20 23:59:59

->whereDate('start_datetime', '<=', $date)->whereDate('end_datetime', '>=', $date)

Carbon::parse("2021/11/28")->format('Y-m-d');   //2021-11-28

Carbon::parse("2021-12-03 16:00:00")->subHour(1);  //2021-12-03 15:00:00

$diff_in_minutes = (Carbon::now())->diffInMinutes('09:00:00', false);