Re: FETCH FIRST clause WITH TIES option

On 2019-Nov-28, Surafel Temesgen wrote:

> On Thu, Nov 28, 2019 at 12:36 AM Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
> wrote:
>
> > I think you should add a /* fall-though */ comment after changing state.
> > Like this (this flow seems clearer; also DRY):
> >
> > if (!node->noCount &&
> > node->position - node->offset >= node->count)
> > {
> > if (node->limitOption == LIMIT_OPTION_COUNT)
> > {
> > node->lstate = LIMIT_WINDOWEND;
> > return NULL;
> > }
> > else
> > {
> > node->lstate = LIMIT_WINDOWEND_TIES;
> > /* fall-through */
> > }
> > }
> > else
> > ...
>
> changed

But you did not read my code snippet, did you ...?

> > I think you need to stare a that thing a little harder.
>
> This is because the new state didn't know about backward scan
> and there was off by one error it scan one position past to detect
> ties. The attached patch fix both

Oh, thanks, glad it was that easy.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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