Re: Heap WARM Tuples - Design Draft - Mailing list pgsql-hackers

From Claudio Freire
Subject Re: Heap WARM Tuples - Design Draft
Date
Msg-id CAGTBQpY_bJ-ARu0eqBSuN87y4v4xJkw2evMkXGZoKyTZ2Ou7zA@mail.gmail.com
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In response to Heap WARM Tuples - Design Draft  (Pavan Deolasee <pavan.deolasee@gmail.com>)
List pgsql-hackers
On Thu, Aug 4, 2016 at 7:59 AM, Pavan Deolasee <pavan.deolasee@gmail.com> wrote:
> So marking the index would require us to mark both old and new index tuples
> as requiring re-check. That requires an additional index scan to locate the
> old row and then an additional write to force it to re-check, which is
> algorithmically O(NlogN) on table size.


So, basically, I'm saying this isn't really O(NlogN), it's O(N),
manifested in low-cardinality indexes.



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