Joris Van den Bossche created ARROW-8729: --------------------------------------------
Summary: [C++][Dataset] Only selecting a partition column results in empty table Key: ARROW-8729 URL: https://issues.apache.org/jira/browse/ARROW-8729 Project: Apache Arrow Issue Type: Bug Components: C++ Reporter: Joris Van den Bossche Fix For: 1.0.0 Python reproducer: {code} import pyarrow as pa import pyarrow.parquet as pq import pyarrow.dataset as ds path = "test_dataset" table = pa.table({'part': ['a', 'a', 'b', 'b'], 'col': [1, 2, 3, 4]}) pq.write_to_dataset(table, str(path), partition_cols=["part"]) {code} gives {code} In [38]: ds.dataset(str(path), partitioning="hive").to_table().num_rows Out[38]: 4 In [39]: ds.dataset(str(path), partitioning="hive").to_table(columns=["part"]).num_rows Out[39]: 0 {code} The schema correctly only includes the "part" column, but there are no rows. cc [~bkietz] -- This message was sent by Atlassian Jira (v8.3.4#803005)