[GitHub] [arrow-rs] tustvold opened a new issue, #1537: Support Empty Column Projection in ParquetRecordBatchReader

[GitBox <gi...@apache.org>]

tustvold opened a new issue, #1537:
URL: https://github.com/apache/arrow-rs/issues/1537

   **Is your feature request related to a problem or challenge? Please describe what you are trying to do.**
   
   If an empty array is passed to `ArrowReader::get_record_reader_by_columns` it returns an error.
   
   **Describe the solution you'd like**
   
   It would be advantageous to support an empty projection within ParquetRecordBatchReader, and instead use file metadata to return the requisite number of rows. This will need the ability to create a RecordBatch with no columns and a non-zero row count #1536 
   
   **Describe alternatives you've considered**
   
   We could not add this functionality
   
   **Additional context**
   
   This would simplify the implementation of Hive based partitioning, amongst other things - https://github.com/apache/arrow-datafusion/pull/2000
   


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[GitHub] [arrow-rs] alamb closed issue #1537: Support Empty Column Projection in ParquetRecordBatchReader

[GitBox <gi...@apache.org>]

alamb closed issue #1537: Support Empty Column Projection in ParquetRecordBatchReader
URL: https://github.com/apache/arrow-rs/issues/1537


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