Re: Append's first_partial_plan

David Rowley wrote:
> On 18 April 2018 at 07:52, Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> wrote:
> > While looking at this patch I became curious as to why do we even have
> > first_partial_plan in the first place; it seems to require some strange
> > contortions in the code. Wouldn't it be simpler to have two lists, one
> > for non-partial and another for partial paths? I went to check the
> > original discussion, and this design was indeed considered [1] -- but
> > the idea was discarded because using the list index would lead to
> > simpler code. However, now that we have pruning it seems to me that
> > using the index isn't simpler anymore. Should we revisit this now?
>
> I don't think having two Lists and/or two AppendState arrays would
> make the pruning code anymore simple. All the pruning code in
> execPartition.c would need to determine the index within the partial
> or non-partial subnode array, and also communicate which array it
> means. That code did take me a while to get right and be readable
> too, I don't really want to have to change it again. I really don't
> think it would look quite as simple as it does today either, so -1
> from me for changing this.

Got it.

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