We are creating an application which will share objects with other users in the same group. For instance, when object A is created by user 1, and user 2 is added to the same group, the object A has to be available for user 2.

Currently, the user_id is saved for the objects, and there are found based on this ID:

$q = A::where('user_id', Auth::$user->id); return $q->get();

However, we want to return al the objects from A from all the users who are in a group. My instinct would to make a user_group table and a usergroups table to link users to each other and replace Auth::$user->id with all id's from the group(s) the user is in. But is that the optimal method, from an performance perspective?