@Override
 @Transactional(propagation = Propagation.REQUIRED, isolation = Isolation.DEFAULT)
 public Shop loadShopByGuid(String guid) {
   return shopDao.findByGuid(Shop.class, guid);
 }
 @Override
 public CommentAttachment loadCommentAttachment(String guid) {
   return shopDao.findByGuid(CommentAttachment.class, guid);
 }