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https://issues.apache.org/jira/browse/ARROW-17459?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17598383#comment-17598383
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Arthur Passos commented on ARROW-17459:
---------------------------------------

[~emkornfield] if I understand correctly, this could help with the original 
case I shared. In the case [~willjones127] shared, where he creates a 
ChunkedArray and then serializes it, it wouldn't help. Is that correct?

I am stating this based on my current understanding of the inner workings of 
`arrow`: The ChunkedArray data structure will be used in two or more 
situations: 
1. The data in a row group exceeds the limit of INT_MAX (Case I initially 
shared)
2. The serialized data/ table is a chunked array, thus it makes sense to use a 
chunked array.

 

> [C++] Support nested data conversions for chunked array
> -------------------------------------------------------
>
>                 Key: ARROW-17459
>                 URL: https://issues.apache.org/jira/browse/ARROW-17459
>             Project: Apache Arrow
>          Issue Type: New Feature
>          Components: C++
>            Reporter: Arthur Passos
>            Priority: Blocker
>
> `FileReaderImpl::ReadRowGroup` fails with "Nested data conversions not 
> implemented for chunked array outputs". It fails on 
> [ChunksToSingle]([https://github.com/apache/arrow/blob/7f6b074b84b1ca519b7c5fc7da318e8d47d44278/cpp/src/parquet/arrow/reader.cc#L95])
> Data schema is: 
> {code:java}
>   optional group fields_map (MAP) = 217 {
>     repeated group key_value {
>       required binary key (STRING) = 218;
>       optional binary value (STRING) = 219;
>     }
>   }
> fields_map.key_value.value-> Size In Bytes: 13243589 Size In Ratio: 0.20541047
> fields_map.key_value.key-> Size In Bytes: 3008860 Size In Ratio: 0.046667963
> {code}
> Is there a way to work around this issue in the cpp lib?
> In any case, I am willing to implement this, but I need some guidance. I am 
> very new to parquet (as in started reading about it yesterday).
>  
> Probably related to: https://issues.apache.org/jira/browse/ARROW-10958



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