Exception while selecting a none-encoded text with Arrow

[cdessanti]

As reported in the community forum https://community.omnisci.com/communities/community-home/digestviewer/viewthread?MessageKey=9b5b5ce9-baba-4780-b8d2-3291530a220c&CommunityKey=d06df790-8ca4-4e54-91a0-244af0228ddc&tab=digestviewer#bm9b5b5ce9-baba-4780-b8d2-3291530a220c

selecting a text filed with encoding none will raise the following exception:
TMapDException(error_msg='Exception: TEXT is not supported in Arrow result sets.').

steps to reproduce the error

DDL & dataload

create table test_string_ne (iden integer,desc_de text encoding dict(32), desc_ne text encoding none);
insert into test_string_ne values (1,'aaaa','bbbb');

python call

>>> df = conn.select_ipc('select desc_de,iden from test_string_ne');
>>> df.head()
  desc_de  iden
0    aaaa     1
>>> df = conn.select_ipc('select desc_ne from test_string_ne');
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/mapd/.local/lib/python3.6/site-packages/pymapd/connection.py", line 315, in select_ipc
    first_n=first_n
  File "/home/mapd/.local/lib/python3.6/site-packages/mapd/MapD.py", line 1560, in sql_execute_df
    return self.recv_sql_execute_df()
  File "/home/mapd/.local/lib/python3.6/site-packages/mapd/MapD.py", line 1588, in recv_sql_execute_df
    raise result.e
mapd.ttypes.TMapDException: TMapDException(error_msg='Exception: TEXT is not supported in Arrow result sets.')

Selecting the text column not encoded, you will get the exception while selecting other fields is fine.