David Rowley wrote: > On 18 April 2018 at 07:52, Alvaro Herrera <alvhe...@alvh.no-ip.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/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
