title: Why CoreData does not provide class named NSDeleteRequest like NSFetchRequest
body: <p>I was wondering why CoreData framework of iPhone does not provide the facility to delete objects from database in a group using NSPredicate. They have provided way to fetch data with NSFetchRequest, but I do not find any method or class to delete the objects in a group with NSPredicate. For example I want to delete those objects from customers table where balance of customer is zero. I can do this with for loop in core data but I wanted to know why the apple has not provided the way to delete objects in this way?</p>