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Matthew Rocklin commented on ARROW-1983: ---------------------------------------- My understanding is that there is already a standard around using a "_metadata" file that presumably is expected to have certain data laid out in a certain way. It may be that [~mdurant] can provide a nice reference to the expectations. It also looks like PyArrow has a nice reader for this information. If I open up a Parquet Dataset that has a `_metadata` file I find that my object has all of the right information, so that might also be a good place to look. > [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 > Fix For: 0.14.0 > > > 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. -- This message was sent by Atlassian JIRA (v7.6.3#76005)