// Without eager loading (N+1 problem)
foreach (App\Models\Post::all() as $post) {
    echo $post->user->name; // Each user access makes a new query
}

// With eager loading (solves N+1 problem)
$posts = App\Models\Post::with('user')->get();
foreach ($posts as $post) {
    echo $post->user->name; // User is already loaded, no extra queries
}

// Eager loading multiple relationships
$posts = App\Models\Post::with(['user', 'comments'])->get();

// Eager loading with constraints
$posts = App\Models\Post::with(['comments' => function ($query) {
    $query->where('approved', 1);
}])->get();