Column 'department_id' in where clause is ambiguous - laravel

Question

I got error on my page like the title above.
I am trying to export an Excel with the Laravel Excel extension.
Here is my code:
public function query()
{
$test = Leave::query()
->join('departments as dep', 'leaves.department_id', '=', 'dep.id')
->join('employees as emp', 'leaves.employee_id', '=', 'emp.id')
->join('users as emplUser', 'emp.user_id', '=', 'emplUser.id')
->join('users as apprUser', 'leaves.approved_by_id', '=', 'apprUser.id')
->select('leaves.id',
'dep.name',
'emplUser.first_name',
'leaves.start',
'leaves.end',
'leaves.type',
'leaves.reason',
'leaves.approved',
'leaves.approved_on',
'apprUser.first_name',
'leaves.approved_comment',
'leaves.created_at',
'leaves.updated_at',
)
->whereDate('leaves.start','>=', $this->periodStart)
->whereDate('leaves.end', '<=', $this->periodEnd);
return $test;
}
and here is the SQL from the error message:
select
`leaves`.`id`,
`dep`.`name`,
`emplUser`.`first_name`,
`leaves`.`start`,
`leaves`.`end`,
`leaves`.`type`,
`leaves`.`reason`,
`leaves`.`approved`,
`leaves`.`approved_on`,
`apprUser`.`first_name`,
`leaves`.`approved_comment`,
`leaves`.`created_at`,
`leaves`.`updated_at`
from `leaves`
inner join `departments` as `dep` on `leaves`.`department_id` = `dep`.`id`
inner join `employees` as `emp` on `leaves`.`employee_id` = `emp`.`id`
inner join `users` as `emplUser` on `emp`.`user_id` = `emplUser`.`id`
inner join `users` as `apprUser` on `leaves`.`approved_by_id` = `apprUser`.`id`
where date(`leaves`.`start`) >= 2021-07-04 and date(`leaves`.`end`) <= 2021-12-31
and (`department_id` = 2 or `department_id` is null)
order by `leaves`.`id` asc limit 1000 offset 0
I have notice that it says:
where ... and (`department_id` = 2 or `department_id` is null)
But I have never specified department_id, just like the start and end date. I think it needs like leaves.department_id, but how can I do that when I have never write it from the first time?
Update with more code:
This is from the LeaveController:
public function export()
{
$now = Carbon::now()->startOfWeek(Carbon::SUNDAY);
$start = $now;
$end = $now->copy()->endOfYear();
$period = new Period($start, $end);
return (new LeavesExport)->forPeriod($period->start, $period->end)->download('download.xlsx');
}
This is some of the code from Leave, that I found that contains department in some way:
use App\Traits\HasDepartment;
* App\Leave
* #property int $department_id
* #property-read \App\Department $department
* #method static \Illuminate\Database\Eloquent\Builder|\App\Leave whereDepartmentId( $value )
class Leave extends Model
{
use HasDepartment, ...
public static function getTypes()
{
try {
return LeaveType::where('department_id', current_department()->id)->pluck('name', 'id');
} catch (\Exception $e) {
error_log('User id: ' . auth()->user()->id . ' does not have an assigned Department');
return collect([]);
}
}
}

Answer 1

The error in your WHERE clause is ambiguous means that the system is not able to indentify department_id because there are more than 1 column with that name. You need to specify it first.
return LeaveType::where('leaves.department_id', current_department()->id)->pluck('name', 'id');