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https://issues.apache.org/jira/browse/ARROW-1983?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16853378#comment-16853378
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Rick Zamora commented on ARROW-1983:
------------------------------------

I submitted a PR to perform the metadata aggregation and metadata-only file 
write ([https://github.com/apache/arrow/pull/4405]).  I just syncronized with 
the master branch, so hopefully I can address any suggestions/concerns people 
have relatively quickly.

Are there any additional features that we need for "utilizing" the metadata 
file within arrow.parque itself?  I believe the existing read_metadata function 
should be sufficient for the needs of dask.

> [Python] Add ability to write parquet `_metadata` file
> ------------------------------------------------------
>
>                 Key: ARROW-1983
>                 URL: https://issues.apache.org/jira/browse/ARROW-1983
>             Project: Apache Arrow
>          Issue Type: Improvement
>          Components: C++, Python
>            Reporter: Jim Crist
>            Priority: Major
>              Labels: beginner, parquet, pull-request-available
>             Fix For: 0.14.0
>
>          Time Spent: 6.5h
>  Remaining Estimate: 0h
>
> Currently {{pyarrow.parquet}} can only write the {{_common_metadata}} file 
> (mostly just schema information). It would be useful to add the ability to 
> write a {{_metadata}} file as well. This should include information about 
> each row group in the dataset, including summary statistics. Having this 
> summary file would allow filtering of row groups without needing to access 
> each file beforehand.
> This would require that the user is able to get the written RowGroups out of 
> a {{pyarrow.parquet.write_table}} call and then give these objects as a list 
> to new function that then passes them on as C++ objects to {{parquet-cpp}} 
> that generates the respective {{_metadata}} file.



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