[ARROW-14104] Reading Lists of Timestamps from parquet files in Arrow 5.0.0 fails to preserve the TimeZone - unlike in Arrow 4.0.0

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Not A Problem
• Affects Version/s: 5.0.0
• Component/s: C++, Parquet, Python
• External issue URL: https://github.com/apache/arrow/issues/29695
• Assignee: Unassigned
• Reporter: Sarah Gilmore
• Created: 23/Sep/21 15:24
• Updated: 11/Jan/23 08:37
• Resolved: 26/Oct/21 13:41

Description

In Arrow 4.0.0 it is possible to round-trip the TimeZone property of List<Timestamp> columns to and from parquet files: 

>>> import pyarrow as pa
>>> import pyarrow.parquet as pq
>>> import datetime 

>>> column = pa.array([[datetime.datetime(2023, 9, 23, 11)]], pa.list_(pa.timestamp('us', 'America/New_York')));

>>> t = pa.Table.from_arrays([column], names=['TimestampColumn']);
>>> pq.write_table(t, "example.parq");

>>> t2 = pq.read_table("example.parq");
>>> t2
pyarrow.Table
Dates: list<item: timestamp[us, tz=America/New_York]>
  child 0, item: timestamp[us, tz=America/New_York]

However, if you read the same parquet file in pyarrow 5.0.0, the TimeZone is set to UTC:

>>> t3 = pq.read_table("example.parq");
>>> t3
pyarrow.Table
Dates: list<item: timestamp[us, tz=UTC]>
  child 0, item: timestamp[us, tz=UTC]
 

 

I noticed that the TimeZone is preserved in Arrow 5.0 when reading non-nested timestamp columns.