Peter Geoghegan <> writes:
> On Fri, Aug 12, 2016 at 4:30 PM, Peter Geoghegan <> wrote:
>> Doesn't tuplesort_heap_siftup() actually shift-down?

The reason it's called siftup is that that's what Knuth calls it.
See Algorithm 5.2.3H (Heapsort), pp 146-147 in the first edition of
Volume 3; tuplesort_heap_siftup corresponds directly to steps H3-H8.

> Heikki (CC'd) and I discussed this privately today, and we were in
> agreement that this needs to be fixed, so I wrote a patch, which I
> attach here.

I think this patch is misguided, as it unnecessarily moves the code
away from standard nomenclature.

                        regards, tom lane

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