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Re: Todo: Teach planner to evaluate multiple windows in the optimal order - Mailing list pgsql-hackers

From David Rowley
Subject Re: Todo: Teach planner to evaluate multiple windows in the optimal order
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Msg-id CAApHDvr0CscJDDgPDvjwQc8M8WBvfTzfAkehxJBw1qOVO-oqAw@mail.gmail.com
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In response to Re: Todo: Teach planner to evaluate multiple windows in the optimal order  (Ankit Kumar Pandey <itsankitkp@gmail.com>)
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On Sun, 8 Jan 2023 at 01:52, Ankit Kumar Pandey <itsankitkp@gmail.com> wrote:
> I am just wondering though, why can we not do top-N sort
> in optimized version if we include limit clause? Is top-N sort is
> limited to non strict sorting or
> cases last operation before limit is sort? .

Maybe the sort bound can be pushed down. You'd need to adjust
ExecSetTupleBound() so that it pushes the bound through
WindowAggState.

David

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