diff --git a/internal/querynode/collection_replica.go b/internal/querynode/collection_replica.go
index efa2b86f00bc03018dbd23bd7de99be9ad2966d4..adfcfca345fb47f8197ae089141c69bee7121852 100644
--- a/internal/querynode/collection_replica.go
+++ b/internal/querynode/collection_replica.go
@@ -63,6 +63,7 @@ type ReplicaInterface interface {
 	getPKFieldIDByCollectionID(collectionID UniqueID) (FieldID, error)
 
 	// partition
+	// addPartition adds a new partition to collection
 	addPartition(collectionID UniqueID, partitionID UniqueID) error
 	removePartition(partitionID UniqueID) error
 	getPartitionByID(partitionID UniqueID) (*Partition, error)