From 422d14d667ac72d0ffb75ca4df9a8ca24431b885 Mon Sep 17 00:00:00 2001
From: jian he <jian.universality@gmail.com>
Date: Sun, 10 May 2026 12:13:09 +0800
Subject: [PATCH v4 1/2] export ExecInsert

The ExecInsert function encapsulates core logic for the insertion pipeline,
including partition routing, BEFORE ROW triggers, INSTEAD OF triggers, and AFTER
ROW triggers and others.

exporting ExecInsert, the COPY FROM command can leverage the exact same
execution path as standard inserts.

discussion: https://postgr.es/m/CACJufxG672yotDt87Dbazf1C9scnZm7QSB+zu6vHc+j5QrjXvA@mail.gmail.com
commitfest entry: https://commitfest.postgresql.org/patch/6736/
---
 src/backend/executor/nodeModifyTable.c | 40 +----------------------
 src/include/executor/nodeModifyTable.h | 45 ++++++++++++++++++++++++++
 2 files changed, 46 insertions(+), 39 deletions(-)

diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 478cb01783c..85f3df7c09a 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -84,44 +84,6 @@ typedef struct MTTargetRelLookup
 	int			relationIndex;	/* rel's index in resultRelInfo[] array */
 } MTTargetRelLookup;
 
-/*
- * Context struct for a ModifyTable operation, containing basic execution
- * state and some output variables populated by ExecUpdateAct() and
- * ExecDeleteAct() to report the result of their actions to callers.
- */
-typedef struct ModifyTableContext
-{
-	/* Operation state */
-	ModifyTableState *mtstate;
-	EPQState   *epqstate;
-	EState	   *estate;
-
-	/*
-	 * Slot containing tuple obtained from ModifyTable's subplan.  Used to
-	 * access "junk" columns that are not going to be stored.
-	 */
-	TupleTableSlot *planSlot;
-
-	/*
-	 * Information about the changes that were made concurrently to a tuple
-	 * being updated or deleted
-	 */
-	TM_FailureData tmfd;
-
-	/*
-	 * The tuple deleted when doing a cross-partition UPDATE with a RETURNING
-	 * clause that refers to OLD columns (converted to the root's tuple
-	 * descriptor).
-	 */
-	TupleTableSlot *cpDeletedSlot;
-
-	/*
-	 * The tuple projected by the INSERT's RETURNING clause, when doing a
-	 * cross-partition UPDATE
-	 */
-	TupleTableSlot *cpUpdateReturningSlot;
-} ModifyTableContext;
-
 /*
  * Context struct containing output data specific to UPDATE operations.
  */
@@ -868,7 +830,7 @@ ExecGetUpdateNewTuple(ResultRelInfo *relinfo,
  *		save the previous value to avoid losing track of it.
  * ----------------------------------------------------------------
  */
-static TupleTableSlot *
+TupleTableSlot *
 ExecInsert(ModifyTableContext *context,
 		   ResultRelInfo *resultRelInfo,
 		   TupleTableSlot *slot,
diff --git a/src/include/executor/nodeModifyTable.h b/src/include/executor/nodeModifyTable.h
index f6070e1cdf3..250bd64ad15 100644
--- a/src/include/executor/nodeModifyTable.h
+++ b/src/include/executor/nodeModifyTable.h
@@ -13,8 +13,47 @@
 #ifndef NODEMODIFYTABLE_H
 #define NODEMODIFYTABLE_H
 
+#include "access/tableam.h"
 #include "nodes/execnodes.h"
 
+/*
+ * Context struct for a ModifyTable operation, containing basic execution
+ * state and some output variables populated by ExecUpdateAct() and
+ * ExecDeleteAct() to report the result of their actions to callers.
+ */
+typedef struct ModifyTableContext
+{
+	/* Operation state */
+	ModifyTableState *mtstate;
+	EPQState   *epqstate;
+	EState	   *estate;
+
+	/*
+	 * Slot containing tuple obtained from ModifyTable's subplan.  Used to
+	 * access "junk" columns that are not going to be stored.
+	 */
+	TupleTableSlot *planSlot;
+
+	/*
+	 * Information about the changes that were made concurrently to a tuple
+	 * being updated or deleted
+	 */
+	TM_FailureData tmfd;
+
+	/*
+	 * The tuple deleted when doing a cross-partition UPDATE with a RETURNING
+	 * clause that refers to OLD columns (converted to the root's tuple
+	 * descriptor).
+	 */
+	TupleTableSlot *cpDeletedSlot;
+
+	/*
+	 * The tuple projected by the INSERT's RETURNING clause, when doing a
+	 * cross-partition UPDATE
+	 */
+	TupleTableSlot *cpUpdateReturningSlot;
+} ModifyTableContext;
+
 extern void ExecInitGenerated(ResultRelInfo *resultRelInfo,
 							  EState *estate,
 							  CmdType cmdtype);
@@ -24,6 +63,12 @@ extern void ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo,
 									   CmdType cmdtype);
 
 extern ModifyTableState *ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags);
+extern TupleTableSlot *ExecInsert(ModifyTableContext *context,
+								  ResultRelInfo *resultRelInfo,
+								  TupleTableSlot *slot,
+								  bool canSetTag,
+								  TupleTableSlot **inserted_tuple,
+								  ResultRelInfo **insert_destrel);
 extern void ExecEndModifyTable(ModifyTableState *node);
 extern void ExecReScanModifyTable(ModifyTableState *node);
 
-- 
2.34.1