code: @Override
    public <SN,N> MutationResult subDelete(final K key, final String cf, final SN supercolumnName,
        final N columnName, final Serializer<SN> sNameSerializer, final Serializer<N> nameSerializer) {
      return new MutationResultImpl(keyspace.doExecute(new KeyspaceOperationCallback<Void>() {
        @Override
        public Void doInKeyspace(KeyspaceService ks) throws HectorException {
          ks.remove(keySerializer.toByteBuffer(key), ThriftFactory.createSuperColumnPath(cf,
              supercolumnName, columnName, sNameSerializer, nameSerializer));
          return null;
        }
      }, consistency));
    }
docs: Deletes a subcolumn of a supercolumn
  @param <SN> super column type
  @param <N> subcolumn type