Kato-san, On Thu, Jul 4, 2019 at 1:40 PM Kato, Sho <kato-...@jp.fujitsu.com> wrote: > > If I understand the details of [1] correctly, ModifyTable will no longer > > have N subplans for N result relations as there are today. So, it doesn't > > make sense for ModifyTable to contain PartitionedRelPruneInfos and for > > ExecInitModifyTable/ExecModifyTable > > to have to perform initial and execution-time pruning, respectively. > > Does this mean that the generic plan will not have N subplans for N result > relations? > I thought [1] would make creating generic plans faster, but is this correct?
Yeah, making a generic plan for UPDATE of inheritance tables will certainly become faster, because we will no longer plan the same query N times for N child tables. There will still be N result relations but only one sub-plan to fetch the rows from. Also, planning will still cost O(N), but with a much smaller constant factor. By the way, let's keep any further discussion on this particular topic in the other thread. Thanks, Amit