Core Data applying delete rule when updating
<p>Beginner in Core Data here, there is something very basic in Core Data that I don't understand. I know the delete rules, such that if my object gets deleted, if it has relationships that are cascade for example, those relationships will get deleted as well. But what happens on updates?</p>

<p>Example:
Person has a relationship to a car. Delete rule is cascade.
Person --> Car
If Person is deleted, Car will be gone too.
But now what if Person just points to another Car, the previous Car will NOT be deleted and will just be dangling in the DB.
Any solutions to this?</p>

<p>I figured ideally you should delete the first car before setting the new one, but this is automatically done from a server fetch.</p>