$dean_ids = Auth::user()->dean_id; // "9,11"
$subjects = Subject::whereIn('dean_id', [$dean_ids])->select('id')->get();
returns only data for "9" but when i trying like this:
$subjects = Subject::whereIn('dean_id', [9,11])->select('id')->get();
//it returns all data that what i want.
how can i fix it?