title: NSPredicate search for child entity instance based on property of parent entity
body: <p>Im trying to do a search for a child entity based on a field "guid".  The guid field is defined in the parent entity.  I would like to find the child instance whos guid is equal to some value i pass in but it always returns a result of 0 values.  Im assuming core data isn't seeing the guid property since its defined in the parent entity.</p>
  
  <p>Here is my predicate:</p>
  
  <pre><code>NSFetchRequest *request = [[NSFetchRequest alloc] init];
  
  [request setEntity:[NSEntityDescription entityForName:CHILD_ENTITY inManagedObjectContext:managedObjectContext]];
  [request setPredicate:[NSPredicate predicateWithFormat:@"(guid like '%@')", guid]];
  
  NSError *error = nil;
  
  NSArray *results = [managedObjectContext executeFetchRequest:request error:&amp;error];
  
  if (results != nil &amp;&amp; results.count &gt; 0)
      return YES;
  else 
      return NO;
  </code></pre>
  
  <p>Is my predicate format wrong? </p>