I look the algolithm validate index_col's after connecting to bq. However I think this validation before connecting is convenience.

So python:pandas/pandas/io/gbq.py if index_col is not None: if index_col in final_df.columns: final_df.set_index(index_col, inplace=True) else: raise InvalidColumnOrder( 'Index column "{0}" does not exist in DataFrame.' .format(index_col) ) line 713 to 720 move to line 697

Comment From: KeiMae

Sorry my misunderstanding. It's optional... However It don't work when I set nothing....

Comment From: jreback

support for gbq has moved to https://github.com/pydata/pandas-gbq

you can file an issue there, though pls show a reproducible example.