ARROW-7045: [R] Preserve factor in Parquet roundtrip #6135
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nealrichardson
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Jan 7, 2020
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Thanks for this! LGTM
This makes me question whether default_arrow_writer_properties is right or useful, given that both R and Python are no longer using it. Should this store_schema behavior be pushed down to C++? @wesm
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The ability to preserve categorical values was introduced in #5077 as the convention of storing a special
ARROW:schemakey in the metadata. To invoke this, we need to callArrowWriterProperties::store_schema().The R binding is already ready for this, but calls
store_schema()only conditionally and usesparquet___default_arrow_writer_properties()by default. Though I don't see the motivation to implement as such in #5451, considering the Python binding always callsstore_schema(), I guess the R code can do the same.