laravel model save relation code example
Example 1: laravel eloquent without relation
$books = Book::without('author')->get();
Example 2: associate laravel
When updating a belongsTo relationship, you may use the associate method. This
method will set the foreign key on the child model:
$account = App\Account::find(10);
$user->account()->associate($account);
$user->save();
When removing a belongsTo relationship, you may use the dissociate method. This
method will set the relationship foreign key to null:
$user->account()->dissociate();
$user->save();