On 17/01/2020 07:20, Kyotaro Horiguchi wrote: > Thank you for the notification, Tomas. > > At Thu, 16 Jan 2020 22:33:58 +0100, Tomas Vondra > <tomas.von...@2ndquadrant.com> wrote in >> This patch is marked as RFC since September. Since then there was no >> discussion on this thread, but Andrew proposed an alternative approach >> based on window functions in a separate thread [1] (both for this and >> for the WITH TIES case). >> >> I'll set this patch back to "needs review" - at this point we need to >> decide which of the approaches is the right one. > Even consdiering that we have only two usage , WITH TIES and PERCENT, > of the mechanism for now, I like [1] for the generic nature, > simpleness and smaller invasiveness to executor. The fact that cursor > needs materialize to allow backward scan would not be a big problem. > It seems that PERCENT will be easily implemented on that. > > However, isn't there a possibility that we allow FETCH FIRST x PERCENT > WITH TIES, though I'm not sure what SQL spec tells about that? I > don't come up right now how to do that using window functions..
PERCENT and WITH TIES can play together, per spec. -- Vik Fearing
