Hi Henson, > Hi all, > > A quick heads-up for this thread, cross-referenced from another one. > > Haibo Yan has a patch series adding DISTINCT support to plain aggregate > window functions [1]. As it touches window-aggregate frame handling, I > applied it on top of the current RPR patch set and built the two together. > They combine cleanly today: no rebase conflict, and the regression tests > pass with no change to code or tests. > > This is structural, not luck. RPR requires the frame to start at CURRENT > ROW, while that feature requires UNBOUNDED PRECEDING, so a single window can > satisfy at most one of them -- no overlap. > > That said, the DISTINCT roadmap plans to relax its UNBOUNDED-PRECEDING > restriction (the sliding-frame patches), while RPR's CURRENT-ROW requirement > is fixed by the standard. So as those frame restrictions are lifted the two > could start to overlap, and at that point we'd likely need to review the > related frame-handling changes together. Nothing to act on now -- just > flagging it so we keep an eye on it. > > Full review of the DISTINCT series is in the other thread [1]. > > [1] > https://www.postgresql.org/message-id/caaae_zcfvbnrouf5fae38ecwybtxacthr9xdve2ujjpedsl...@mail.gmail.com
Thanks for letting know us! -- Tatsuo Ishii SRA OSS K.K. English: http://www.sraoss.co.jp/index_en/ Japanese:http://www.sraoss.co.jp
