From c621467d2bc6435d07db4471998ca9c9f0c57777 Mon Sep 17 00:00:00 2001 From: Etsuro Fujita Date: Thu, 21 Sep 2023 19:45:00 +0900 Subject: [PATCH] Update comment about set_join_pathlist_hook(). The comment introduced by commit e7cb7ee14 was a bit too terse, which could lead to extensions doing different things within the hook function than we intend to allow. Extend the comment to explain what they can do within the hook function. Back-patch to all supported branches. In passing, I rephrased a nearby comment that I recently added to the back branches. Reviewed by David Rowley and Andrei Lepikhov. Discussion: https://postgr.es/m/CAPmGK15SBPA1nr3Aqsdm%2BYyS-ay0Ayo2BRYQ8_A2To9eLqwopQ%40mail.gmail.com --- src/backend/optimizer/path/joinpath.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/src/backend/optimizer/path/joinpath.c b/src/backend/optimizer/path/joinpath.c index 821d282497..b2916ad690 100644 --- a/src/backend/optimizer/path/joinpath.c +++ b/src/backend/optimizer/path/joinpath.c @@ -333,7 +333,10 @@ add_paths_to_joinrel(PlannerInfo *root, jointype, &extra); /* - * 6. Finally, give extensions a chance to manipulate the path list. + * 6. Finally, give extensions a chance to manipulate the path list. They + * could add new paths (such as CustomPaths) by calling add_path(), or + * add_partial_path() if parallel aware. They could also delete or modify + * paths added by the core code. */ if (set_join_pathlist_hook) set_join_pathlist_hook(root, joinrel, outerrel, innerrel,