ClifHouck commented on code in PR #40957: URL: https://github.com/apache/arrow/pull/40957#discussion_r1549959277
########## cpp/src/parquet/encoding.cc: ########## @@ -3988,4 +3988,21 @@ std::unique_ptr<Decoder> MakeDictDecoder(Type::type type_num, } } // namespace detail + +// Informed heavily by https://github.com/apache/parquet-format/blob/master/Encodings.md +// Should we also consider if we're in dictionary encoding mode? or assume no for the +// moment? +Encoding::type ChooseFallbackEncoding(Type::type data_type, + ParquetVersion::type parquet_version, + ParquetDataPageVersion datapage_version) { + if (data_type == Type::BOOLEAN && parquet_version != ParquetVersion::PARQUET_1_0 && + datapage_version == ParquetDataPageVersion::V2) { + return Encoding::RLE; + } else if (data_type == Type::BYTE_ARRAY) { Review Comment: I do, though it's not immediately clear to me what the best encoding to choose for other data types is. The docs make it crystal clear in the case of `BYTE_ARRAY`, but not necessarily other types as far as I can tell. -- 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]
