How to add multiple key constraints for ORM eager loading in Laravel?

Question

Suppose I have three relations:

 1. departments
        - id (primary)
        - name
 2. quotas
        - id (primary)
        - name
 3. department_quota
        - id (primary)
        - department_id (foreign)
        - quota_id (foreign)
        - number_of_seats
        - unique(department_id, quota_id)

Now, I want to access number_of_seats per department grouped by quota, again I want to access number_of_seats per quota grouped by department. I need to do this task using laravel ORM eager loading.

I can access all quotas with departments using :

\App\Quota::with('departments')->get();

and also the opposite thing using by:

\App\Department::with('quotas')->get();

Yes, this is a many-to-many relation. But how can I access the number_of_seats as stated above ?

I need this because I am to serve the relation as JSON serialized data for REST.

Answer 1

If both models are belongsToMany you can add withPivot() to your departments() method.

public function departments(){
    return $this->belongsToMany('App\Department')->withPivot('number_of_seats');
}

it will be included in the json collection and it can be reached via code with

foreach(Quota::with('departments')->get() as $quota){
       foreach($quota->departments as $department){
           echo $department->pivot->number_of_seats;
       }
    }