lue can be one of: ``'table'`` Table format. Write as a PyTables Table structure which may perform worse but allow more flexible operations like searching / selecting subsets of the data. index : bool, default True Write DataFrame index as a column. append : bool, default True Append the input data to the existing. data_columns : list of columns, or True, default None List of columns to create as indexed data columns for on-disk queries, or True to use all columns. By default only the axes of the object are indexed. See `here `__. min_itemsize : dict of columns that specify minimum str sizes nan_rep : str to use as str nan representation chunksize : size to chunk the writing expectedrows : expected TOTAL row size of this table encoding : default None, provide an encoding for str dropna : bool, default False, optional Do not write an ALL nan row to the store settable by the option 'io.hdf.dropna_table'. Notes ----- Does *not* check if data being appended overlaps with existing data in the table, so be careful Nz>columns is not a supported keyword in append, try data_columnsz