diff --git a/internal/querynode/flow_graph_insert_node.go b/internal/querynode/flow_graph_insert_node.go
index b2528c5cb4..d95046f7a8 100644
--- a/internal/querynode/flow_graph_insert_node.go
+++ b/internal/querynode/flow_graph_insert_node.go
@@ -244,6 +244,7 @@ func processDeleteMessages(replica ReplicaInterface, msg *msgstream.DeleteMsg, d
 	}
 }
 
+// filterSegmentsByPKs would filter segments by primary keys
 func filterSegmentsByPKs(pks []int64, segment *Segment) ([]int64, error) {
 	if pks == nil {
 		return nil, fmt.Errorf("pks is nil when getSegmentsByPKs")