如何在Laravel 5.3中使用多态关系？

I am using laravel 5.3 and I have a scenario as follows

I have 2 models

  1. Robot
  2. Location

A Robot can have many Locations but a location can belong to only 1 Robot, and each time a Robot have a new location the count field in location Table will increment

what I am trying to is that I want to use polymorph relation with Laravel and Eloquent, I want to get all the Locations of all Robots by last updated by using distinct() ?

By the way, Locatable_id in location table is refers to Robot ID. here is my models

Robot Model

public function locations() {
      return $this->morphMany('App\Models\Location', 'locatable');
    }

Location Model

public function locatable() {
      return $this->morphTo();

}

Locations Table

enter image description here

Any help would be really appreciated. Thanks.

The query below returns all the robots and for each one provides the latest location. The inner function could be used to filter the locations data.

Robot::with(['locations' => function($q) {
    $q->latest();
}])->get();


what I am trying to is that I want to use polymorph relation with Laravel and Eloquent, I want to get all the Locations of all Robots by last updated by using distinct() ?

This doesn't completely reach your goal but I think that is a good point to start.

Here is how I did solve it :)

// Grap all Robots with it's locations and Customer
  $robots = Robot::whereHas('locations', function($query){
    $query->whereNotNull('locatable_id')->orderBy('updated_at');
  })->with('locations')->with('customers')->get();

//Filter only latest Locations for each Robot
  $filterLocations= $robots->map(function($robot){
    $robot->timeEntries = $robot->locations()
      ->orderBy('updated_at', 'DESC')
      ->limit(1)
      ->get();
    return $robot;
  });

Appreciate your spending time for helping out :) Thank you samuele-colombo