Studying Espresso can take a few hours and is best done while not under pressure to deliver results. The Help file explains each phrase. Whichever way you learn Espresso, we know it will be very useful. Views take very little storage. A user with full write resource permissions is very unlikely to consume more than 1MB of database space.
DBsurfer users have no control over that.
However, you can redesign this arrangement easily. Say you need to find out regularly the average grades for a particular course description. The description is in the Course entity, the grades in the Grade entity. If these entities are large, that might take longer than necessary. Your database now looks like this and you can design exactly the same Espresso query, but DBsurfer will see that there is a short-circuit and take the shorter path automatically .