I'm working on an iPhone application with a few data relationships (Author -> Books for example). When a user deletes an Author object from the application, I have a few SQLite triggers that run on the delete to remove any books from the database that have a foreign key matching the Author's primary key. 

I'm also using a trigger to insert some data when a new item is created. 

I can't help but shake the feeling that this might be bad design or lead to some problems down the road I am not thinking of. That said, should I rely on code in my app to handle propagating the deletes like this when the database has the capability built in to handle it? 

What say you?