Remove redundant code in create_gather_merge_path In create_gather_merge_path, we should always guarantee that the subpath is adequately ordered, and we do not add a Sort node in createplan.c for a Gather Merge node. Therefore, the 'else' branch in create_gather_merge_path, which computes the cost for a Sort node, is redundant.
This patch removes the redundant code and emits an error if the subpath is not sufficiently ordered. Meanwhile, this patch changes the check for the subpath's pathkeys in create_gather_merge_plan to an Assert. Author: Richard Guo Discussion: https://postgr.es/m/CAMbWs48u=0bWf3epVtULjJ-=M9Hbkz+ieZQAOS=bfbxzfqb...@mail.gmail.com Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/8b2e9fd26afd9f379ea8bedeb4b11a354c09a3e1 Modified Files -------------- src/backend/optimizer/plan/createplan.c | 9 ++------- src/backend/optimizer/util/pathnode.c | 35 +++++++++++---------------------- 2 files changed, 14 insertions(+), 30 deletions(-)
