[ARROW-9634] [C++][Python] Restore non-UTC time zones when reading Parquet file that was previously Arrow

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 4.0.0
• Component/s: C++, Python
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/25695
• Assignee: Joris Van den Bossche
• Reporter: Wes McKinney
• Created: 03/Aug/20 16:37
• Updated: 11/Jan/23 08:08
• Resolved: 27/Jan/21 17:38

Description

This was reported on the mailing list

In [20]: df = pd.DataFrame({'a': pd.Series(np.arange(0, 10000, 1000)).astype(pd.DatetimeTZDtype('ns', 'America/Los_Angeles'
    ...: ))})                                                                                                              

In [21]: t = pa.table(df)                                                                                                  

In [22]: t                                                                                                                 
Out[22]: 
pyarrow.Table
a: timestamp[ns, tz=America/Los_Angeles]

In [23]: pq.write_table(t, 'test.parquet')                                                                                 

In [24]: pq.read_table('test.parquet')                                                                                     
Out[24]: 
pyarrow.Table
a: timestamp[us, tz=UTC]

In [25]: pq.read_table('test.parquet')[0]                                                                                  
Out[25]: 
<pyarrow.lib.ChunkedArray object at 0x7f72eb4b68f0>
[
  [
    1970-01-01 00:00:00.000000,
    1970-01-01 00:00:00.000001,
    1970-01-01 00:00:00.000002,
    1970-01-01 00:00:00.000003,
    1970-01-01 00:00:00.000004,
    1970-01-01 00:00:00.000005,
    1970-01-01 00:00:00.000006,
    1970-01-01 00:00:00.000007,
    1970-01-01 00:00:00.000008,
    1970-01-01 00:00:00.000009
  ]
]

Issue Links

• links to: GitHub Pull Request #9336