Alexander Korotkov 505c008ca3 Restore preprocess_groupclause() ... 0452b461bc made optimizer explore alternative orderings of group-by pathkeys. It eliminated preprocess_groupclause(), which was intended to match items between GROUP BY and ORDER BY. Instead, get_useful_group_keys_orderings() function generates orderings of GROUP BY elements at the time of grouping paths generation. The get_useful_group_keys_orderings() function takes into account 3 orderings of GROUP BY pathkeys and clauses: original order as written in GROUP BY, matching ORDER BY clauses as much as possible, and matching the input path as much as possible. Given that even before 0452b461b, preprocess_groupclause() could change the original order of GROUP BY clauses we don't need to consider it apart from ordering matching ORDER BY clauses. This commit restores preprocess_groupclause() to provide an ordering of GROUP BY elements matching ORDER BY before generation of paths. The new version of preprocess_groupclause() takes into account an incremental sort. The get_useful_group_keys_orderings() function now takes into 2 orderings of GROUP BY elements: the order generated preprocess_groupclause() and the order matching the input path as much as possible. Discussion: https://postgr.es/m/CAPpHfdvyWLMGwvxaf%3D7KAp-z-4mxbSH8ti2f6mNOQv5metZFzg%40mail.gmail.com Author: Alexander Korotkov Reviewed-by: Andrei Lepikhov, Pavel Borisov		2024-06-06 13:44:34 +03:00
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allpaths.c	Re-allow planner to use Merge Append to efficiently implement UNION.	2024-05-21 12:44:51 -04:00
clausesel.c	Remove unused #include's from backend .c files	2024-03-04 12:02:20 +01:00
costsize.c	Do not translate dummy SpecialJoinInfos for child joins	2024-03-25 18:06:47 +09:00
equivclass.c	Fix asymmetry in setting EquivalenceClass.ec_sortref	2024-06-06 13:41:34 +03:00
indxpath.c	Revert: Remove useless self-joins	2024-05-06 14:36:36 +03:00
joinpath.c	Postpone reparameterization of paths until create_plan().	2024-03-19 14:51:58 -04:00
joinrels.c	Code review for 6190d828cd	2024-03-25 19:45:27 +09:00
Makefile	Split all OBJS style lines in makefiles into one-line-per-entry style.	2019-11-05 14:41:07 -08:00
meson.build	Update copyright for 2024	2024-01-03 20:49:05 -05:00
pathkeys.c	Restore preprocess_groupclause()	2024-06-06 13:44:34 +03:00
tidpath.c	Prevent RLS filters on ctid from breaking WHERE CURRENT OF <cursor>.	2024-05-07 13:35:10 -04:00