Avoid listing the same ResultRelInfo in more than one EState list.

Doing so causes EXPLAIN ANALYZE to show trigger statistics multiple
times.  Commit 2f17844104 seems to
be to blame for this.

Amit Langote, revieed by Amit Khandekar, Etsuro Fujita, and me.

src/backend/commands/explain.c

@@ -652,15 +652,18 @@ ExplainPrintTriggers(ExplainState *es, QueryDesc *queryDesc)
 	bool		show_relname;
 	int			numrels = queryDesc->estate->es_num_result_relations;
 	int			numrootrels = queryDesc->estate->es_num_root_result_relations;
-	List	   *leafrels = queryDesc->estate->es_leaf_result_relations;
-	List	   *targrels = queryDesc->estate->es_trig_target_relations;
+	List	   *routerels;
+	List	   *targrels;
 	int			nr;
 	ListCell   *l;
 
+	routerels = queryDesc->estate->es_tuple_routing_result_relations;
+	targrels = queryDesc->estate->es_trig_target_relations;
+
 	ExplainOpenGroup("Triggers", "Triggers", false, es);
 
 	show_relname = (numrels > 1 || numrootrels > 0 ||
-					leafrels != NIL || targrels != NIL);
+					routerels != NIL || targrels != NIL);
 	rInfo = queryDesc->estate->es_result_relations;
 	for (nr = 0; nr < numrels; rInfo++, nr++)
 		report_triggers(rInfo, show_relname, es);
@@ -669,7 +672,7 @@ ExplainPrintTriggers(ExplainState *es, QueryDesc *queryDesc)
 	for (nr = 0; nr < numrootrels; rInfo++, nr++)
 		report_triggers(rInfo, show_relname, es);
 
-	foreach(l, leafrels)
+	foreach(l, routerels)
 	{
 		rInfo = (ResultRelInfo *) lfirst(l);
 		report_triggers(rInfo, show_relname, es);

src/backend/executor/execMain.c

@@ -1413,8 +1413,11 @@ ExecGetTriggerResultRel(EState *estate, Oid relid)
 		rInfo++;
 		nr--;
 	}
-	/* Third, search through the leaf result relations, if any */
-	foreach(l, estate->es_leaf_result_relations)
+	/*
+	 * Third, search through the result relations that were created during
+	 * tuple routing, if any.
+	 */
+	foreach(l, estate->es_tuple_routing_result_relations)
 	{
 		rInfo = (ResultRelInfo *) lfirst(l);
 		if (RelationGetRelid(rInfo->ri_RelationDesc) == relid)

src/backend/executor/execPartition.c

@@ -178,6 +178,15 @@ ExecSetupPartitionTupleRouting(ModifyTableState *mtstate,
 							  resultRTindex,
 							  rel,
 							  estate->es_instrument);
+
+			/*
+			 * Since we've just initialized this ResultRelInfo, it's not in
+			 * any list attached to the estate as yet.  Add it, so that it can
+			 * be found later.
+			 */
+			estate->es_tuple_routing_result_relations =
+						lappend(estate->es_tuple_routing_result_relations,
+								leaf_part_rri);
 		}
 
 		part_tupdesc = RelationGetDescr(partrel);
@@ -210,9 +219,6 @@ ExecSetupPartitionTupleRouting(ModifyTableState *mtstate,
 							mtstate != NULL &&
 							mtstate->mt_onconflict != ONCONFLICT_NONE);
 
-		estate->es_leaf_result_relations =
-			lappend(estate->es_leaf_result_relations, leaf_part_rri);
-
 		proute->partitions[i] = leaf_part_rri;
 		i++;
 	}

src/backend/executor/execUtils.c

@@ -119,7 +119,7 @@ CreateExecutorState(void)
 	estate->es_root_result_relations = NULL;
 	estate->es_num_root_result_relations = 0;
 
-	estate->es_leaf_result_relations = NIL;
+	estate->es_tuple_routing_result_relations = NIL;
 
 	estate->es_trig_target_relations = NIL;
 	estate->es_trig_tuple_slot = NULL;

src/include/nodes/execnodes.h

@@ -466,8 +466,11 @@ typedef struct EState
 	ResultRelInfo *es_root_result_relations;	/* array of ResultRelInfos */
 	int			es_num_root_result_relations;	/* length of the array */
 
-	/* Info about leaf partitions of partitioned table(s) for insert queries: */
-	List	   *es_leaf_result_relations;	/* List of ResultRelInfos */
+	/*
+	 * The following list contains ResultRelInfos created by the tuple
+	 * routing code for partitions that don't already have one.
+	 */
+	List	   *es_tuple_routing_result_relations;
 
 	/* Stuff used for firing triggers: */
 	List	   *es_trig_target_relations;	/* trigger-only ResultRelInfos */