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A comment on Show HN: pg_flame – flamegraph visualizations of PostgreSQL query plans. Parent comment

Re:Show HN: pg_flame – flamegraph visualizations of PostgreS... by btown on Sunday October 27, 2019 @08:31PM (#21373413)
I would love to be able to SET multiple_planning; on a cursor to be able to say “yes I know that reversing would be UB, and I have set a limit so I don’t care if results aren’t streamed, so please just try everything you can.” In general I wish there were better ways to tell these systems you know what you’re doing.
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Re:Show HN: pg_flame – flamegraph visualizations of PostgreS... by cormacrelf on Monday October 28, 2019 @12:40AM (#21374328)
There could also be a “clean the slate” streaming directive, which means “I started the query again, please scratch what got delivered already”.
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Re:Show HN: pg_flame – flamegraph visualizations of PostgreS... by JelteF on Monday October 28, 2019 @04:41AM (#21375226)
That effictively means the client cannot actually start processing the results before everything is received. Because you would have to undo everything you did with the data you received before. So basically this would simply be a non streaming version.
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Re:Show HN: pg_flame – flamegraph visualizations of PostgreS... by Bootvis on Monday October 28, 2019 @05:13AM (#21375383)
I believe the best you can do is to delay streaming. Now you have the problem of deciding when to start...
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