scovich opened a new pull request, #8299: URL: https://github.com/apache/arrow-rs/pull/8299
# Which issue does this PR close? We generally require a GitHub issue to be filed for all bug fixes and enhancements and this helps us generate change logs for our releases. You can link an issue to this PR using the GitHub syntax. - Closes #NNN. # Rationale for this change The original `cast_to_variant` code did columnar conversions of types to variant. For primitive types this worked ok, but for deeply nested types it means repeatedly creating new variants (and variant metadata), only to re-code them by copying the variant values to new arrays (with new metadata and field ids). Very expensive. # What changes are included in this PR? Follow the example of https://github.com/apache/arrow-rs/pull/8280, and introduce a row builder concept that takes individual array values and writes them to an `impl VariantBuilderExt`. # Are these changes tested? Existing unit tests continue to pass. Extensive new unit tests added as well. # Are there any user-facing changes? * `VariantBuilderExt` has a new `append_null` method. * `ObjectFieldBuilder` moved to `builder.rs` and made public -- 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: github-unsubscr...@arrow.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
