[
https://issues.apache.org/jira/browse/ARROW-14104?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Sarah Gilmore updated ARROW-14104:
----------------------------------
Description:
In Arrow 4.0.0 it is possible to round-trip the TimeZone property of
List<Timestamp> columns to and from parquet files:
{code:java}
>>> 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], name=['TimestampColumn']);
>>> pq.write_table(t, "example.parq", version='2.0');
>>> t2 = pq.read_table("example.parq");
>>> t2
pyarrow.Table
Dates: list<item: timestamp[us, tz=America/Denver]>
child 0, item: timestamp[us, tz=America/Denver]
{code}
However, if you read the same parquet file in pyarrow 5.0.0, the TimeZone is
set to UTC:
{code:java}
>>> t3 = pq.read_table("example.parq");
>>> t3
pyarrow.Table
Dates: list<item: timestamp[us, tz=UTC]>
child 0, item: timestamp[us, tz=UTC]
{code}
I noticed that the TimeZone is preserved in Arrow 5.0 when reading non-nested
timestamp columns.
was:
In Arrow 4.0.0 it is possible to round-trip the TimeZone property of
List<Timestamp> columns to and from parquet files:
{code:java}
>>> 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], name=['TimestampColumn']);
>>> pq.write_table(t, "example.parq");
>>> t2 = pq.read_table("example.parq");
>>> t2
pyarrow.Table
Dates: list<item: timestamp[us, tz=America/Denver]>
child 0, item: timestamp[us, tz=America/Denver]
{code}
However, if you read the same parquet file in pyarrow 5.0.0, the TimeZone is
set to UTC:
{code:java}
>>> t3 = pq.read_table("example.parq");
>>> t3
pyarrow.Table
Dates: list<item: timestamp[us, tz=UTC]>
child 0, item: timestamp[us, tz=UTC]
{code}
I noticed that the TimeZone is preserved in Arrow 5.0 when reading non-nested
timestamp columns.
> Reading Lists of Timestamps from parquet files in Arrow 5.0.0 fails to
> preserve the TimeZone - unlike in Arrow 4.0.0
> --------------------------------------------------------------------------------------------------------------------
>
> Key: ARROW-14104
> URL: https://issues.apache.org/jira/browse/ARROW-14104
> Project: Apache Arrow
> Issue Type: Bug
> Components: C++, Parquet, Python
> Affects Versions: 5.0.0
> Reporter: Sarah Gilmore
> Priority: Minor
>
> In Arrow 4.0.0 it is possible to round-trip the TimeZone property of
> List<Timestamp> columns to and from parquet files:
> {code:java}
> >>> 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], name=['TimestampColumn']);
> >>> pq.write_table(t, "example.parq", version='2.0');
> >>> t2 = pq.read_table("example.parq");
> >>> t2
> pyarrow.Table
> Dates: list<item: timestamp[us, tz=America/Denver]>
> child 0, item: timestamp[us, tz=America/Denver]
> {code}
> However, if you read the same parquet file in pyarrow 5.0.0, the TimeZone is
> set to UTC:
> {code:java}
> >>> t3 = pq.read_table("example.parq");
> >>> t3
> pyarrow.Table
> Dates: list<item: timestamp[us, tz=UTC]>
> child 0, item: timestamp[us, tz=UTC]
> {code}
>
> I noticed that the TimeZone is preserved in Arrow 5.0 when reading non-nested
> timestamp columns.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
