onboard/app/Models/Department.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Department extends Model
{
    public $timestamps = false;

    protected $primaryKey = 'department_id';

    protected $fillable = [
        'name_full',
        'name_short',
        'rf_mis_department_id',
        'rf_department_type'
    ];

    public function metrikaDefault()
    {
        return $this->hasMany(DepartmentMetrikaDefault::class, 'rf_department_id', 'department_id');
    }

    public function observationPatients(): \Illuminate\Database\Eloquent\Relations\HasMany
    {
        return $this->hasMany(ObservationPatient::class, 'rf_department_id', 'department_id');
    }

    public function reports(): \Illuminate\Database\Eloquent\Relations\HasMany
    {
        return $this->hasMany(Report::class, 'rf_department_id', 'department_id');
    }

    public function departmentType()
    {
        return $this->belongsTo(DepartmentType::class, 'rf_department_type', 'department_type_id');
    }
}