shyjsarah opened a new issue, #596: URL: https://github.com/apache/paimon-rust/issues/596
### Motivation Paimon Rust can now read `merge-engine=partial-update` tables with sequence groups after #584, but it still rejects existing Java/Flink-created tables that configure: - `fields.<field>.aggregate-function` - `fields.default-aggregate-function` This prevents Rust and DataFusion readers from opening partial-update tables that aggregate protected fields within sequence groups. Treating these tables as basic latest-non-null partial update would be incorrect, especially when an older sequence-group row must be combined in reverse order. I searched the existing issues and did not find one covering partial-update field aggregation reads. This is a follow-up to #583 / #584. ### Proposed scope Add read-side field aggregation support for partial-update tables: - parse and validate per-field and default aggregate-function options; - reuse the aggregate functions already implemented in Paimon Rust; - support `last_non_null_value` without a sequence group, matching Java validation; - require other configured aggregate functions to protect fields in a sequence group; - apply normal aggregation when an incoming group sequence is newer or equal; - apply Java-compatible reversed aggregation when an incoming group sequence is older; - preserve sequence-group projection dependency widening; - fail closed with a clear error for unknown or type-incompatible aggregate functions; - add merge-level and end-to-end projected-read tests. ### Out of scope To keep the contribution reviewable: - adding Java-only aggregate-function families that are not currently implemented in Rust; - DELETE / UPDATE_BEFORE retraction and remove-record semantics; - Rust writer and CREATE/ALTER support for partial-update aggregation. ### Willingness to contribute I'm willing to submit a PR for this scoped read-side support. -- 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]
