You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@arrow.apache.org by "Uwe L. Korn (JIRA)" <ji...@apache.org> on 2018/04/16 18:37:00 UTC
[jira] [Updated] (ARROW-1983) [Python] Add ability to write parquet
`_metadata` file
[ https://issues.apache.org/jira/browse/ARROW-1983?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Uwe L. Korn updated ARROW-1983:
-------------------------------
Description:
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.
was: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.
> [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: Python
> Reporter: Jim Crist
> Priority: Major
> Fix For: 0.10.0
>
>
> 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)