Remove partColsUpdated.

This information appears to have been unused since commit
c5b7ba4e67.  We could not find any references in third-party code,
either.

Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/aO_CyFRpbVMtgJWM%40nathan

src/backend/optimizer/plan/createplan.c

@@ -311,7 +311,6 @@ static ProjectSet *make_project_set(List *tlist, Plan *subplan);
 static ModifyTable *make_modifytable(PlannerInfo *root, Plan *subplan,
 									 CmdType operation, bool canSetTag,
 									 Index nominalRelation, Index rootRelation,
-									 bool partColsUpdated,
 									 List *resultRelations,
 									 List *updateColnosLists,
 									 List *withCheckOptionLists, List *returningLists,
@@ -2676,7 +2675,6 @@ create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path)
 							best_path->canSetTag,
 							best_path->nominalRelation,
 							best_path->rootRelation,
-							best_path->partColsUpdated,
 							best_path->resultRelations,
 							best_path->updateColnosLists,
 							best_path->withCheckOptionLists,
@@ -7010,7 +7008,6 @@ static ModifyTable *
 make_modifytable(PlannerInfo *root, Plan *subplan,
 				 CmdType operation, bool canSetTag,
 				 Index nominalRelation, Index rootRelation,
-				 bool partColsUpdated,
 				 List *resultRelations,
 				 List *updateColnosLists,
 				 List *withCheckOptionLists, List *returningLists,
@@ -7047,7 +7044,6 @@ make_modifytable(PlannerInfo *root, Plan *subplan,
 	node->canSetTag = canSetTag;
 	node->nominalRelation = nominalRelation;
 	node->rootRelation = rootRelation;
-	node->partColsUpdated = partColsUpdated;
 	node->resultRelations = resultRelations;
 	if (!onconflict)
 	{

src/backend/optimizer/plan/planner.c

@@ -744,7 +744,6 @@ subquery_planner(PlannerGlobal *glob, Query *parse, char *plan_name,
 	else
 		root->wt_param_id = -1;
 	root->non_recursive_path = NULL;
-	root->partColsUpdated = false;
 
 	/*
 	 * Create the top-level join domain.  This won't have valid contents until
@@ -2127,7 +2126,6 @@ grouping_planner(PlannerInfo *root, double tuple_fraction,
 										parse->canSetTag,
 										parse->resultRelation,
 										rootRelation,
-										root->partColsUpdated,
 										resultRelations,
 										updateColnosLists,
 										withCheckOptionLists,

src/backend/optimizer/util/inherit.c

@@ -335,16 +335,6 @@ expand_partitioned_rtentry(PlannerInfo *root, RelOptInfo *relinfo,
 	/* A partitioned table should always have a partition descriptor. */
 	Assert(partdesc);
 
-	/*
-	 * Note down whether any partition key cols are being updated. Though it's
-	 * the root partitioned table's updatedCols we are interested in,
-	 * parent_updatedCols provided by the caller contains the root partrel's
-	 * updatedCols translated to match the attribute ordering of parentrel.
-	 */
-	if (!root->partColsUpdated)
-		root->partColsUpdated =
-			has_partition_attrs(parentrel, parent_updatedCols, NULL);
-
 	/* Nothing further to do here if there are no partitions. */
 	if (partdesc->nparts == 0)
 		return;

src/backend/optimizer/util/pathnode.c

@@ -3612,8 +3612,6 @@ create_lockrows_path(PlannerInfo *root, RelOptInfo *rel,
  * 'canSetTag' is true if we set the command tag/es_processed
  * 'nominalRelation' is the parent RT index for use of EXPLAIN
  * 'rootRelation' is the partitioned/inherited table root RTI, or 0 if none
- * 'partColsUpdated' is true if any partitioning columns are being updated,
- *		either from the target relation or a descendent partitioned table.
  * 'resultRelations' is an integer list of actual RT indexes of target rel(s)
  * 'updateColnosLists' is a list of UPDATE target column number lists
  *		(one sublist per rel); or NIL if not an UPDATE
@@ -3630,7 +3628,6 @@ create_modifytable_path(PlannerInfo *root, RelOptInfo *rel,
 						Path *subpath,
 						CmdType operation, bool canSetTag,
 						Index nominalRelation, Index rootRelation,
-						bool partColsUpdated,
 						List *resultRelations,
 						List *updateColnosLists,
 						List *withCheckOptionLists, List *returningLists,
@@ -3696,7 +3693,6 @@ create_modifytable_path(PlannerInfo *root, RelOptInfo *rel,
 	pathnode->canSetTag = canSetTag;
 	pathnode->nominalRelation = nominalRelation;
 	pathnode->rootRelation = rootRelation;
-	pathnode->partColsUpdated = partColsUpdated;
 	pathnode->resultRelations = resultRelations;
 	pathnode->updateColnosLists = updateColnosLists;
 	pathnode->withCheckOptionLists = withCheckOptionLists;

src/include/nodes/pathnodes.h

@@ -593,9 +593,6 @@ struct PlannerInfo
 	bool	   *isAltSubplan pg_node_attr(read_write_ignore);
 	bool	   *isUsedSubplan pg_node_attr(read_write_ignore);
 
-	/* Does this query modify any partition key columns? */
-	bool		partColsUpdated;
-
 	/* PartitionPruneInfos added in this query's plan. */
 	List	   *partPruneInfos;
 
@@ -2609,7 +2606,6 @@ typedef struct ModifyTablePath
 	bool		canSetTag;		/* do we set the command tag/es_processed? */
 	Index		nominalRelation;	/* Parent RT index for use of EXPLAIN */
 	Index		rootRelation;	/* Root RT index, if partitioned/inherited */
-	bool		partColsUpdated;	/* some part key in hierarchy updated? */
 	List	   *resultRelations;	/* integer list of RT indexes */
 	List	   *updateColnosLists;	/* per-target-table update_colnos lists */
 	List	   *withCheckOptionLists;	/* per-target-table WCO lists */

src/include/nodes/plannodes.h

@@ -338,8 +338,6 @@ typedef struct ModifyTable
 	Index		nominalRelation;
 	/* Root RT index, if partitioned/inherited */
 	Index		rootRelation;
-	/* some part key in hierarchy updated? */
-	bool		partColsUpdated;
 	/* integer list of RT indexes */
 	List	   *resultRelations;
 	/* per-target-table update_colnos lists */

src/include/optimizer/pathnode.h

@@ -281,7 +281,6 @@ extern ModifyTablePath *create_modifytable_path(PlannerInfo *root,
 												Path *subpath,
 												CmdType operation, bool canSetTag,
 												Index nominalRelation, Index rootRelation,
-												bool partColsUpdated,
 												List *resultRelations,
 												List *updateColnosLists,
 												List *withCheckOptionLists, List *returningLists,