v6-0001-mark_async_capable-subpath-should-match-subplan.patch

From 044ff10f402c0cbc4f815a34fc266e4e581274c0 Mon Sep 17 00:00:00 2001
From: Alexander Pyhalov <a.pyhalov@postgrespro.ru>
Date: Sat, 15 Nov 2025 10:16:25 +0300
Subject: [PATCH 1/2] mark_async_capable(): subpath should match subplan

create_append_plan() calls mark_async_capable() on subplan of
Append and corresponding subpath. Later mark_async_capable()
looks at path type and decides that subplan has type, corresponding
to the path type. However, this is not true if create_append_plan()
inserts Sort node above Append subplan. So we should handle such case
separately.
---
 src/backend/optimizer/plan/createplan.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index 8af091ba647..004bbc6d1d6 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -1139,10 +1139,10 @@ mark_async_capable_plan(Plan *plan, Path *path)
 				SubqueryScan *scan_plan = (SubqueryScan *) plan;
 
 				/*
-				 * If the generated plan node includes a gating Result node,
-				 * we can't execute it asynchronously.
+				 * If the generated plan node includes a gating Result node or
+				 * a Sort node, we can't execute it asynchronously.
 				 */
-				if (IsA(plan, Result))
+				if (IsA(plan, Result) || IsA(plan, Sort))
 					return false;
 
 				/*
@@ -1160,10 +1160,10 @@ mark_async_capable_plan(Plan *plan, Path *path)
 				FdwRoutine *fdwroutine = path->parent->fdwroutine;
 
 				/*
-				 * If the generated plan node includes a gating Result node,
-				 * we can't execute it asynchronously.
+				 * If the generated plan node includes a gating Result node or
+				 * a Sort node, we can't execute it asynchronously.
 				 */
-				if (IsA(plan, Result))
+				if (IsA(plan, Result) || IsA(plan, Sort))
 					return false;
 
 				Assert(fdwroutine != NULL);
@@ -1176,9 +1176,9 @@ mark_async_capable_plan(Plan *plan, Path *path)
 
 			/*
 			 * If the generated plan node includes a Result node for the
-			 * projection, we can't execute it asynchronously.
+			 * projection or a Sort node, we can't execute it asynchronously.
 			 */
-			if (IsA(plan, Result))
+			if (IsA(plan, Result) || IsA(plan, Sort))
 				return false;
 
 			/*
-- 
2.43.0