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https://issues.apache.org/jira/browse/ARROW-8657?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17096862#comment-17096862
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Wes McKinney commented on ARROW-8657:
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> As a result all parquet files that were created with ParquetVersion::V2 to
> get features such as unsigned int32s, timestamps with nanosecond resolution,
> etc are now unreadable. That's TBs of data in my case.
To clarify, they are _not_ unreadable, but rather they are not _forward
compatible_ (files written by 0.17.0 with {{version='2.0'}} cannot be read with
0.16.0 at the moment). In general, forward compatibility should be approached
carefully. **All** files written by 0.16.0 are readable in 0.17.0
> Distinguish parquet version 2 logical type vs DataPageV2
> --------------------------------------------------------
>
> Key: ARROW-8657
> URL: https://issues.apache.org/jira/browse/ARROW-8657
> Project: Apache Arrow
> Issue Type: Bug
> Components: C++, Python
> Affects Versions: 0.17.0
> Reporter: Pierre Belzile
> Priority: Major
>
> With the recent release of 0.17, the ParquetVersion is used to define the
> logical type interpretation of fields and the selection of the DataPage
> format.
> As a result all parquet files that were created with ParquetVersion::V2 to
> get features such as unsigned int32s, timestamps with nanosecond resolution,
> etc are now unreadable. That's TBs of data in my case.
> Those two concerns should be separated. Given that that DataPageV2 pages were
> not written prior to 0.17 and in order to allow reading existing files, the
> existing version property should continue to operate as in 0.16 and inform
> the logical type mapping.
> Some consideration should be given to issue a release 0.17.1.
>
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