load eager loading laravel code example

Example 1: whereHas site:https://laravel.com/docs/

use Illuminate\Database\Eloquent\Builder;

// Retrieve posts with at least one comment containing words like code%...
$posts = Post::whereHas('comments', function (Builder $query) {
    $query->where('content', 'like', 'code%');
})->get();

// Retrieve posts with at least ten comments containing words like code%...
$posts = Post::whereHas('comments', function (Builder $query) {
    $query->where('content', 'like', 'code%');
}, '>=', 10)->get();

Example 2: morph relation laravel

You may register the morphMap in the boot function of your 
App\Providers\AppServiceProvider class or create a separate service provider 
if you wish.

use Illuminate\Database\Eloquent\Relations\Relation;

Relation::morphMap([
    'post' => 'App\Models\Post',
    'video' => 'App\Models\Video',
]);