Rich-T-kid opened a new issue, #26976: URL: https://github.com/apache/datafusion/issues/26976
When Parquet dictionary promotion is enabled and `binary_as_string` maps a physical `LargeBinary` column to `Dictionary(Int32, Utf8)`, the reader currently emits `LargeBinary` and `DecoderProjection` dictionary-encodes every row. In ClickBench Q23, `pack_byte_to_dictionary` and `GenericByteDictionaryBuilder::append_array` dominate the remaining dictionary regression. The Parquet reader can preserve the on-disk dictionary by reading `Dictionary(Int32, LargeBinary)` and letting the projection cast only the distinct dictionary values to `Utf8`. The same approach applies to Utf8/LargeUtf8 offset-width mismatches. This keeps key decoding native while preserving the table schema and existing cast validation. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
