@Override
 public Row next() {
   CursorLifecycle.checkIdleOrActive(this);
   Row row = scan.next();
   if (row == null) {
     setIdle();
   }
   return row;
 }
 @Override
 public void rebind(HKey hKey, boolean deep) {
   CursorLifecycle.checkIdle(this);
 }