Add row_ref_equals hook for check_exclusion_or_unique_constraint to work with rowid

Author: homper

src/backend/access/heap/heapam_handler.c

@@ -83,6 +83,14 @@ heapam_get_row_ref_type(Relation rel)
 	return ROW_REF_TID;
 }
 
+static bool
+heapam_row_ref_equals(Relation rel, Datum tupleidDatum1, Datum tupleidDatum2)
+{
+	ItemPointer tupleid1 = DatumGetItemPointer(tupleidDatum1);
+	ItemPointer tupleid2 = DatumGetItemPointer(tupleidDatum2);
+	return ItemPointerEquals(tupleid1, tupleid2);
+}
+
 static void
 heapam_free_rd_amcache(Relation rel)
 {
@@ -2979,6 +2987,7 @@ static const TableAmRoutine heapam_methods = {
 
 	.slot_callbacks = heapam_slot_callbacks,
 	.get_row_ref_type = heapam_get_row_ref_type,
+	.row_ref_equals = heapam_row_ref_equals,
 	.free_rd_amcache = heapam_free_rd_amcache,
 
 	.scan_begin = heap_beginscan,

src/backend/executor/execIndexing.c

@@ -1212,7 +1212,26 @@ check_exclusion_or_unique_constraint(Relation heap, Relation index,
 				continue;
 			}
 		} else {
-			/* TODO: Add same thing for rowid if possible */
+			Assert(tupleidDatum > 0);
+			Pointer rowid = DatumGetPointer(tupleidDatum);
+
+			if (PointerIsValid(rowid))
+			{
+				bool	isnull;
+				Datum existing_rowid;
+
+				existing_rowid = slot_getsysattr(existing_slot, RowIdAttributeNumber, &isnull);
+				Assert(!isnull);
+
+				if (table_row_ref_equals(heap, tupleidDatum, existing_rowid))
+				{
+					if (found_self)		/* should not happen */
+						elog(ERROR, "found self tuple multiple times in index \"%s\"",
+							RelationGetRelationName(index));
+					found_self = true;
+					continue;
+				}
+			}
 		}
 
 		/*

src/include/access/tableam.h

@@ -335,6 +335,7 @@ typedef struct TableAmRoutine
 	const TupleTableSlotOps *(*slot_callbacks) (Relation rel);
 
 	RowRefType	(*get_row_ref_type) (Relation rel);
+	bool		(*row_ref_equals)(Relation rel, Datum tupleidDatum1, Datum tupleidDatum2);
 
 	void		(*free_rd_amcache) (Relation rel);
 
@@ -2169,6 +2170,19 @@ table_get_row_ref_type(Relation rel)
 		return ROW_REF_TID;
 }
 
+static inline bool
+table_row_ref_equals(Relation rel, Datum tupleidDatum1, Datum tupleidDatum2)
+{
+	if (rel->rd_tableam)
+		return rel->rd_tableam->row_ref_equals(rel, tupleidDatum1, tupleidDatum2);
+	else
+	{
+		ItemPointer tupleid1 = DatumGetItemPointer(tupleidDatum1);
+		ItemPointer tupleid2 = DatumGetItemPointer(tupleidDatum2);
+		return ItemPointerEquals(tupleid1, tupleid2);
+	}
+}
+
 static inline void
 table_free_rd_amcache(Relation rel)
 {