Rewrite exotic LAST_VALUE/FIRST_VALUE to self-reference.

Open kgyrtkirk opened this issue 1 year ago • 0 comments

rewrite LAST_VALUE(x) OVER (ORDER BY y) to LAG(x,0) OVER (ORDER BY y)
- the current LAST_VALUE logic has no idea about the frame itself; and doesn't care about the order by
not directly to x because some queries get unplannable that way
restrict NTILE from framing - as its not supported
add test to ensure that all of the KNOWN_WINDOW_FNS's framing is accounted for

Fixes #XXXX.

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- [ ] using the concurrency checklist (Remove this item if the PR doesn't have any relation to concurrency.)
[ ] added documentation for new or modified features or behaviors.
[ ] a release note entry in the PR description.
[ ] added Javadocs for most classes and all non-trivial methods. Linked related entities via Javadoc links.
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[ ] added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
[ ] added unit tests or modified existing tests to cover new code paths, ensuring the threshold for code coverage is met.
[ ] added integration tests.
[ ] been tested in a test Druid cluster.

Mar 06 '24 16:03 kgyrtkirk