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Antoine Pitrou commented on ARROW-2450: --------------------------------------- Apparently Parquet produces a null array instead of a list array for that column. > [Python] Saving to parquet fails for empty lists > ------------------------------------------------ > > Key: ARROW-2450 > URL: https://issues.apache.org/jira/browse/ARROW-2450 > Project: Apache Arrow > Issue Type: Bug > Components: Python > Affects Versions: 0.9.0 > Reporter: Uwe L. Korn > Priority: Major > Fix For: 0.9.1 > > > When writing a table to parquet through pandas, if any column includes an > empty list, it fails with a segmentation fault. > Minimal example: > {code} > import pyarrow as pa > import pyarrow.parquet as pq > import pandas as pd > def save(rows): > table1 = pa.Table.from_pandas(pd.DataFrame(rows)) > pq.write_table(table1, 'test-foo.pq') > table2 = pq.read_table('test-foo.pq') > print('ROWS:', rows) > print('TABLE1:', table1.to_pandas(), sep='\n') > print('TABLE2:', table2.to_pandas(), sep='\n') > save([{'val': ['something']}]) > print('---') > save([{'val': []}]) # empty > {code} > Output: > {code} > ROWS: [{'val': ['something']}] > TABLE1: > val > 0 [something] > TABLE2: > val > 0 [something] > --- > ROWS: [{'val': []}] > TABLE1: > val > 0 [] > [1] 13472 segmentation fault (core dumped) python3 test.py > {code} > Versions: > {code} > $ pip3 list | grep pyarrow > pyarrow (0.9.0) > $ python3 --version > Python 3.5.2 > {code} -- This message was sent by Atlassian JIRA (v7.6.3#76005)