Batching up database changes into a single save

gistfile1.m

// Source: Stanford CS193P November 16, 2010 Lecture 16
// Use case: lots of Core Data changes. You want them to save once they settle down.

- (void)delayedSave:(NSManagedObjectContext *)ctxt 
{
    [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(doSave:) object:ctxt];
    [self performSelector:@selector(doSave:) withObject:ctxt afterDelay:1.0];
}