Revert "Modified files for MERGE"

This reverts commit 354f13855e.

src/backend/optimizer/plan/createplan.c

@@ -288,13 +288,9 @@ static ModifyTable *make_modifytable(PlannerInfo *root,
 				 CmdType operation, bool canSetTag,
 				 Index nominalRelation, List *partitioned_rels,
 				 bool partColsUpdated,
-				 List *resultRelations,
-				 Index mergeTargetRelation,
-				 List *subplans,
+				 List *resultRelations, List *subplans,
 				 List *withCheckOptionLists, List *returningLists,
-				 List *rowMarks, OnConflictExpr *onconflict,
-				 List *mergeSourceTargetList,
-				 List *mergeActionList, int epqParam);
+				 List *rowMarks, OnConflictExpr *onconflict, int epqParam);
 static GatherMerge *create_gather_merge_plan(PlannerInfo *root,
 						 GatherMergePath *best_path);
 
@@ -2450,14 +2446,11 @@ create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path)
 							best_path->partitioned_rels,
 							best_path->partColsUpdated,
 							best_path->resultRelations,
-							best_path->mergeTargetRelation,
 							subplans,
 							best_path->withCheckOptionLists,
 							best_path->returningLists,
 							best_path->rowMarks,
 							best_path->onconflict,
-							best_path->mergeSourceTargetList,
-							best_path->mergeActionList,
 							best_path->epqParam);
 
 	copy_generic_path_info(&plan->plan, &best_path->path);
@@ -6524,13 +6517,9 @@ make_modifytable(PlannerInfo *root,
 				 CmdType operation, bool canSetTag,
 				 Index nominalRelation, List *partitioned_rels,
 				 bool partColsUpdated,
-				 List *resultRelations,
-				 Index mergeTargetRelation,
-				 List *subplans,
+				 List *resultRelations, List *subplans,
 				 List *withCheckOptionLists, List *returningLists,
-				 List *rowMarks, OnConflictExpr *onconflict,
-				 List *mergeSourceTargetList,
-				 List *mergeActionList, int epqParam)
+				 List *rowMarks, OnConflictExpr *onconflict, int epqParam)
 {
 	ModifyTable *node = makeNode(ModifyTable);
 	List	   *fdw_private_list;
@@ -6556,7 +6545,6 @@ make_modifytable(PlannerInfo *root,
 	node->partitioned_rels = partitioned_rels;
 	node->partColsUpdated = partColsUpdated;
 	node->resultRelations = resultRelations;
-	node->mergeTargetRelation = mergeTargetRelation;
 	node->resultRelIndex = -1;	/* will be set correctly in setrefs.c */
 	node->rootResultRelIndex = -1;	/* will be set correctly in setrefs.c */
 	node->plans = subplans;
@@ -6589,8 +6577,6 @@ make_modifytable(PlannerInfo *root,
 	node->withCheckOptionLists = withCheckOptionLists;
 	node->returningLists = returningLists;
 	node->rowMarks = rowMarks;
-	node->mergeSourceTargetList = mergeSourceTargetList;
-	node->mergeActionList = mergeActionList;
 	node->epqParam = epqParam;
 
 	/*

src/backend/optimizer/plan/planner.c

@@ -794,24 +794,6 @@ subquery_planner(PlannerGlobal *glob, Query *parse,
 		/* exclRelTlist contains only Vars, so no preprocessing needed */
 	}
 
-	foreach(l, parse->mergeActionList)
-	{
-		MergeAction *action = (MergeAction *) lfirst(l);
-
-		action->targetList = (List *)
-			preprocess_expression(root,
-								  (Node *) action->targetList,
-								  EXPRKIND_TARGET);
-		action->qual =
-			preprocess_expression(root,
-								  (Node *) action->qual,
-								  EXPRKIND_QUAL);
-	}
-
-	parse->mergeSourceTargetList = (List *)
-		preprocess_expression(root, (Node *) parse->mergeSourceTargetList,
-							  EXPRKIND_TARGET);
-
 	root->append_rel_list = (List *)
 		preprocess_expression(root, (Node *) root->append_rel_list,
 							  EXPRKIND_APPINFO);
@@ -1553,7 +1535,6 @@ inheritance_planner(PlannerInfo *root)
 									 subroot->parse->returningList);
 
 		Assert(!parse->onConflict);
-		Assert(parse->mergeActionList == NIL);
 	}
 
 	/* Result path must go into outer query's FINAL upperrel */
@@ -1612,15 +1593,12 @@ inheritance_planner(PlannerInfo *root)
 									 partitioned_rels,
 									 partColsUpdated,
 									 resultRelations,
-									 0,
 									 subpaths,
 									 subroots,
 									 withCheckOptionLists,
 									 returningLists,
 									 rowMarks,
 									 NULL,
-									 NULL,
-									 NULL,
 									 SS_assign_special_param(root)));
 }
 
@@ -2151,8 +2129,8 @@ grouping_planner(PlannerInfo *root, bool inheritance_update,
 		}
 
 		/*
-		 * If this is an INSERT/UPDATE/DELETE/MERGE, and we're not being
-		 * called from inheritance_planner, add the ModifyTable node.
+		 * If this is an INSERT/UPDATE/DELETE, and we're not being called from
+		 * inheritance_planner, add the ModifyTable node.
 		 */
 		if (parse->commandType != CMD_SELECT && !inheritance_update)
 		{
@@ -2192,15 +2170,12 @@ grouping_planner(PlannerInfo *root, bool inheritance_update,
 										NIL,
 										false,
 										list_make1_int(parse->resultRelation),
-										parse->mergeTarget_relation,
 										list_make1(path),
 										list_make1(root),
 										withCheckOptionLists,
 										returningLists,
 										rowMarks,
 										parse->onConflict,
-										parse->mergeSourceTargetList,
-										parse->mergeActionList,
 										SS_assign_special_param(root));
 		}
 

src/backend/optimizer/plan/setrefs.c

@@ -851,60 +851,6 @@ set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset)
 						fix_scan_list(root, splan->exclRelTlist, rtoffset);
 				}
 
-				/*
-				 * The MERGE produces the target rows by performing a right
-				 * join between the target relation and the source relation
-				 * (which could be a plain relation or a subquery). The INSERT
-				 * and UPDATE actions of the MERGE requires access to the
-				 * columns from the source relation. We arrange things so that
-				 * the source relation attributes are available as INNER_VAR
-				 * and the target relation attributes are available from the
-				 * scan tuple.
-				 */
-				if (splan->mergeActionList != NIL)
-				{
-					/*
-					 * mergeSourceTargetList is already setup correctly to
-					 * include all Vars coming from the source relation. So we
-					 * fix the targetList of individual action nodes by
-					 * ensuring that the source relation Vars are referenced
-					 * as INNER_VAR. Note that for this to work correctly,
-					 * during execution, the ecxt_innertuple must be set to
-					 * the tuple obtained from the source relation.
-					 *
-					 * We leave the Vars from the result relation (i.e. the
-					 * target relation) unchanged i.e. those Vars would be
-					 * picked from the scan slot. So during execution, we must
-					 * ensure that ecxt_scantuple is setup correctly to refer
-					 * to the tuple from the target relation.
-					 */
-
-					indexed_tlist *itlist;
-
-					itlist = build_tlist_index(splan->mergeSourceTargetList);
-
-					splan->mergeTargetRelation += rtoffset;
-
-					foreach(l, splan->mergeActionList)
-					{
-						MergeAction *action = (MergeAction *) lfirst(l);
-
-						/* Fix targetList of each action. */
-						action->targetList = fix_join_expr(root,
-								action->targetList,
-								NULL, itlist,
-								linitial_int(splan->resultRelations),
-								rtoffset);
-
-						/* Fix quals too. */
-						action->qual = (Node *) fix_join_expr(root,
-								(List *) action->qual,
-								NULL, itlist,
-								linitial_int(splan->resultRelations),
-								rtoffset);
-					}
-				}
-
 				splan->nominalRelation += rtoffset;
 				splan->exclRelRTI += rtoffset;