ad1happy2go commented on PR #19005: URL: https://github.com/apache/hudi/pull/19005#issuecomment-4809054987
Thanks @danny0405. My main point: **the table type shouldn't change the result of an incremental query** — COW vs MOR is a storage detail, not query semantics. Today they diverge: for the same data and the same incremental window, COW returns the correct fully-materialized rows while MOR returns wrong ones — only the changed columns for partial updates, and for `EVENT_TIME_ORDERING` a lower-ordering write can surface over the version that should win. That inconsistency is the bug this PR fixes. On the window concern: it isn't undefined — it's exactly the commit-time range of the incremental query (begin/end instants), the same window COW already uses. The PR doesn't merge "all history": it bounds the merge with an `InstantRange` to the window end and applies the commit-time predicate *after* the merge, so each record changed in the window comes back with its value as of the window end — identical to what COW returns for that same window. So I'd lean toward fixing MOR to match COW rather than steering users to COW, since incremental query is a supported read on MOR. Happy to walk through any specific scenario where the expected output seems ambiguous. -- 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]
