QuakeWang opened a new pull request, #7: URL: https://github.com/apache/paimon-mosaic/pull/7
## Problem Paged buckets store `ALL_NULL` columns as directory entries with `slot_size = 0` and no slot payload. The reader correctly skipped round 2 IO for those slots, but partial projection also used the presence of round 2 ranges to decide whether to construct paged bucket readers. As a result, when a projection requested only all-null columns from a partial paged bucket, the requested column could be dropped from the output. ## Fix Separate the two concepts: - `slot_size > 0` decides whether a projected column needs round 2 IO. - `projected[gi]` decides whether a column needs to appear in the result. The reader now tracks partial paged buckets explicitly and constructs their readers even when no round 2 IO is required. `ALL_NULL` projected slots are materialized with an `ENCODING_ALL_NULL` reader. ## Tests - Added a regression test for projecting only an all-null paged column. - Ran `cargo test --workspace`. - Ran `cargo clippy --workspace --all-targets -- -D warnings`. -- 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]
