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https://issues.apache.org/jira/browse/ARROW-5030?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16804353#comment-16804353
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Wes McKinney commented on ARROW-5030:
-------------------------------------

I fixed some cases where this occurs in ARROW-4688, but it is still possible to 
hit this error for very large row groups (> 2GB of string data in a row group). 
I didn't see a follow up JIRA to this or ARROW-3762 so we can use this one for 
the issue

https://github.com/apache/arrow/blob/master/cpp/src/parquet/arrow/reader.cc#L915

> [Python] read_row_group fails with Nested data conversions not implemented 
> for chunked array outputs
> ----------------------------------------------------------------------------------------------------
>
>                 Key: ARROW-5030
>                 URL: https://issues.apache.org/jira/browse/ARROW-5030
>             Project: Apache Arrow
>          Issue Type: Bug
>    Affects Versions: 0.12.0
>            Reporter: Jakub Okoński
>            Priority: Major
>
> Hey, I'm trying to concatenate two files and to avoid reading everything to 
> memory at once, I wanted to use `read_row_group` for my solution, but it 
> fails.
>  
> I think it's due to fields like these:
> {{pyarrow.Field<to: list<item: string>>}}
>  
> But I'm not sure. Is this a duplicate? The issue linked in the code is 
> resolved 
> https://github.com/apache/arrow/blob/fd0b90a7f7e65fde32af04c4746004a1240914cf/cpp/src/parquet/arrow/reader.cc#L915
>  
> Stacktrace is
>  
> {{  File "/data/teftel/teftel-data/teftel_data/parquet_stream.py", line 163, 
> in read_batches}}
> {{    table = pf.read_row_group(ix, columns=self._columns)}}
> {{  File 
> "/home/kuba/.local/share/virtualenvs/teftel-o6G5iH_l/lib/python3.6/site-packages/pyarrow/parquet.py",
>  line 186, in read_row_group}}
> {{    use_threads=use_threads)}}
> {{  File "pyarrow/_parquet.pyx", line 695, in 
> pyarrow._parquet.ParquetReader.read_row_group}}
> {{  File "pyarrow/error.pxi", line 89, in pyarrow.lib.check_status}}
> {{pyarrow.lib.ArrowNotImplementedError: Nested data conversions not 
> implemented for chunked array outputs}}



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