diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index cd6d72c763..fa069a217c 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -914,6 +914,22 @@ use_physical_tlist(PlannerInfo *root, Path *path, int flags)
 			return false;
 	}
 
+	/*
+	 * For an index-only scan, the "physical tlist" is the index's indextlist.
+	 * We can only return that without a projection if all the index's columns
+	 * are returnable.
+	 */
+	if (path->pathtype == T_IndexOnlyScan)
+	{
+		IndexOptInfo *indexinfo = ((IndexPath *) path)->indexinfo;
+
+		for (i = 0; i < indexinfo->ncolumns; i++)
+		{
+			if (!indexinfo->canreturn[i])
+				return false;
+		}
+	}
+
 	/*
 	 * Also, can't do it if CP_LABEL_TLIST is specified and path is requested
 	 * to emit any sort/group columns that are not simple Vars.  (If they are