title: Using NSFetchedResultsController Without UITableView
body: <p>Is it wrong to use an <code>NSFetchedResultsController</code> purely for data management, i.e., without using it to feed a <code>UITableView</code>?</p>
  
  <p>I have a to-many relationship in a Core Data iPhone app. Whenever data in that relationship changes, I need to perform a calculation which requires that data to be sorted. In Apple's standard Department/Employees example, this would be like determining the median salary in a given Department. Whenever an Employee is added to or removed from that Department, or an Employee's salary changes, the median calculation would need to be performed again.</p>
  
  <p>Keeping data sorted and current and getting notifications when it changes sounds like a great job for <code>NSFetchedResultsController</code>. The only "problem" is that I'm not using a <code>UITableView</code>. In other words, I'm not displaying sorted Employees in a <code>UITableView</code>. I just want an up-to-date sorted array of Employees so I can analyze them behind the scenes. (And, of course, I don't want to write a bunch of code that duplicates much of <code>NSFetchedResultsController</code>.)</p>
  
  <p>Is it a bad idea to use an <code>NSFetchedResultsController</code> purely for data management, i.e., without using it to feed a <code>UITableView</code>? I haven't seen this done anywhere, and thought I might be missing something.</p>