title: How to write a query in Core Data in iPhone
body: <p>I have used core data in my apps. My application works fine in online and offline mode . I have doubt about, how to write a query in Core data(Similar SQLite). I wrote a query and used in SQLite. But I want to know about, how to write a query(select, insert, update, etc,.) using core data.</p>
  
  <p>Please guide me and give me some useful links.</p>