code: @Override
  	public CommerceNotificationAttachment fetchByPrimaryKey(
  		Serializable primaryKey) {
  		Serializable serializable = entityCache.getResult(CommerceNotificationAttachmentModelImpl.ENTITY_CACHE_ENABLED,
  				CommerceNotificationAttachmentImpl.class, primaryKey);
  
  		if (serializable == nullModel) {
  			return null;
  		}
  
  		CommerceNotificationAttachment commerceNotificationAttachment = (CommerceNotificationAttachment)serializable;
  
  		if (commerceNotificationAttachment == null) {
  			Session session = null;
  
  			try {
  				session = openSession();
  
  				commerceNotificationAttachment = (CommerceNotificationAttachment)session.get(CommerceNotificationAttachmentImpl.class,
  						primaryKey);
  
  				if (commerceNotificationAttachment != null) {
  					cacheResult(commerceNotificationAttachment);
  				}
  				else {
  					entityCache.putResult(CommerceNotificationAttachmentModelImpl.ENTITY_CACHE_ENABLED,
  						CommerceNotificationAttachmentImpl.class, primaryKey,
  						nullModel);
  				}
  			}
  			catch (Exception e) {
  				entityCache.removeResult(CommerceNotificationAttachmentModelImpl.ENTITY_CACHE_ENABLED,
  					CommerceNotificationAttachmentImpl.class, primaryKey);
  
  				throw processException(e);
  			}
  			finally {
  				closeSession(session);
  			}
  		}
  
  		return commerceNotificationAttachment;
  	}
docs: Returns the commerce notification attachment with the primary key or returns <code>null</code> if it could not be found.
  
  @param primaryKey the primary key of the commerce notification attachment
  @return the commerce notification attachment, or <code>null</code> if a commerce notification attachment with the primary key could not be found