On Tue, 17 Aug 2021 at 15:56, 李杰(慎追) <adger...@alibaba-inc.com> wrote: > According to my understanding, the parent table of a partitioned table does > not store any tuples. > Then why is "relkind = = RELKIND_PARTITIONED_TABLE" suddenly added here ?
We'll need some sort of ResultRelInfo in the case that all partitions are pruned. Using the one for the partitioned table is convenient. I believe that's required if there are any statement-level triggers on the partitioned table or if there's a RETURNING clause. > There is no comment on this point in the code. > Can you answer my confusion? Be deeply grateful. Yeah maybe. It's not exactly close by, but one in grouping_planner mentions this: /* * We managed to exclude every child rel, so generate a * dummy one-relation plan using info for the top target * rel (even though that may not be a leaf target). * Although it's clear that no data will be updated or * deleted, we still need to have a ModifyTable node so * that any statement triggers will be executed. (This * could be cleaner if we fixed nodeModifyTable.c to allow * zero target relations, but that probably wouldn't be a * net win.) */ David
