Laravel查询预留房间数

// Reservation.php
namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Reservation extends Model
{
    protected $fillable = ['room_id', 'check_in_date', 'check_out_date'];

    public function room()
    {
        return $this->belongsTo(Room::class);
    }
}

// Room.php
namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Room extends Model
{
    protected $fillable = ['room_number'];
}

use App\Models\Reservation;
use Carbon\Carbon;

$start_date = Carbon::parse('2023-10-01');
$end_date = Carbon::parse('2023-10-31');

$reservedRoomsCount = Reservation::whereBetween('check_in_date', [$start_date, $end_date])
    ->orWhereBetween('check_out_date', [$start_date, $end_date])
    ->groupBy('room_id')
    ->count();

echo "Reserved Rooms Count: " . $reservedRoomsCount;