// Bad: N+1 problem (executes N+1 queries)
$posts = App\Models\Post::all();
foreach ($posts as $post) {
    echo $post->user->name; // Each access triggers a new query
}

// Good: Eager loading with `with()` (executes 2 queries)
$postsWithUsers = App\Models\Post::with('user')->get();
foreach ($postsWithUsers as $post) {
    echo $post->user->name; // User is already loaded
}

// Eager loading multiple relationships
$orders = App\Models\Order::with(['customer', 'items', 'items.product'])->get();

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