current_of_index_only_scan_v2.patch

diff --git a/src/backend/executor/execCurrent.c b/src/backend/executor/execCurrent.c
index ce7d4ac..aa2da16 100644
--- a/src/backend/executor/execCurrent.c
+++ b/src/backend/executor/execCurrent.c
@@ -19,6 +19,7 @@
 #include "utils/lsyscache.h"
 #include "utils/portal.h"
 #include "utils/rel.h"
+#include "access/relscan.h"
 
 
 static char *fetch_cursor_param_value(ExprContext *econtext, int paramId);
@@ -183,21 +184,35 @@ execCurrentOf(CurrentOfExpr *cexpr,
 		if (TupIsNull(scanstate->ss_ScanTupleSlot))
 			return false;
 
-		/* Use slot_getattr to catch any possible mistakes */
-		tuple_tableoid =
-			DatumGetObjectId(slot_getattr(scanstate->ss_ScanTupleSlot,
-										  TableOidAttributeNumber,
-										  &lisnull));
-		Assert(!lisnull);
-		tuple_tid = (ItemPointer)
-			DatumGetPointer(slot_getattr(scanstate->ss_ScanTupleSlot,
-										 SelfItemPointerAttributeNumber,
-										 &lisnull));
-		Assert(!lisnull);
-
-		Assert(tuple_tableoid == table_oid);
-
-		*current_tid = *tuple_tid;
+		/* In IndexOnlyScan case, the tuple stored in ss_ScanTupleSlot is a
+		 * virtual tuple that does not have ctid column, so we have to get TID
+		 * from xs_ctup.t_self. */
+		if (IsA(scanstate, IndexOnlyScanState))
+		{
+			IndexScanDesc scan = ((IndexOnlyScanState *)scanstate)->ioss_ScanDesc;
+
+			Assert(RelationGetRelid(scan.heapRelation) == table_oid);
+
+			*current_tid = scan->xs_ctup.t_self;
+		}
+		else
+		{
+			/* Use slot_getattr to catch any possible mistakes */
+			tuple_tableoid =
+				DatumGetObjectId(slot_getattr(scanstate->ss_ScanTupleSlot,
+											  TableOidAttributeNumber,
+											  &lisnull));
+			Assert(!lisnull);
+			tuple_tid = (ItemPointer)
+				DatumGetPointer(slot_getattr(scanstate->ss_ScanTupleSlot,
+											 SelfItemPointerAttributeNumber,
+											 &lisnull));
+			Assert(!lisnull);
+
+			Assert(tuple_tableoid == table_oid);
+
+			*current_tid = *tuple_tid;
+		}
 
 		return true;
 	}