Re: [PATCH] Incremental sort (was: PoC: Partial sort)

On Mon, 24 Jun 2019 at 18:01, James Coleman <jtc331(at)gmail(dot)com> wrote:

> On Mon, Jun 24, 2019 at 12:56 PM Simon Riggs <simon(at)2ndquadrant(dot)com>
> wrote:
>
> > What is the specific use case for this? This sounds quite general case.
>
> They are both general cases in some sense, but the concerns lie mostly
> with what happens when they're unexpectedly encountered. For example,
> if the expected row count or group size is off by a good bit and we
> effectively have to perform a sort of all (or most) possible rows.
>
> If we can get the performance to a point where that misestimated row
> count or group size doesn't much matter, then ISTM including the patch
> becomes a much more obvious total win.
>

I was trying to think of ways of using external information/circumstance to
knowingly avoid negative use cases. i.e. don't treat sort as a black box,
use its context.

--
Simon Riggs http://www.2ndQuadrant.com/
<http://www.2ndquadrant.com/>
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