title: core data : differences between managed object and entities?
body: <p>i would like to understand a bit more Core Data, why do we "fetch" and search for entities while the entities are "inside" managed objects? For example :</p>
  
  <pre><code>NSManagedObjectContext *moc = [self managedObjectContext];  
  NSEntityDescription *entityDescription =
      [NSEntityDescription entityForName:@"Employee" inManagedObjectContext:moc];  
  NSFetchRequest *request = [[[NSFetchRequest alloc] init] autorelease];  
  [request setEntity:entityDescription];
  </code></pre>
  
  <p>also, what does a persistent object store contain? if i understood, the persistent object store takes data from a sqlite file, but then it gets a bit confused, is it : one entity, for one persistent object store, for one data inside the sqlite file?</p>
  
  <p>Thanks for your answers</p>
  
  <p>Paul</p>