diff --git a/internal/storage/binlog_iterator.go b/internal/storage/binlog_iterator.go
index eb05f1a6d2..7ce87b2900 100644
--- a/internal/storage/binlog_iterator.go
+++ b/internal/storage/binlog_iterator.go
@@ -19,7 +19,7 @@ import (
 )
 
 var (
-	// ErrNoMoreRecord is the error that the iterator does not have next record
+	// ErrNoMoreRecord is the error that the iterator does not have next record.
 	ErrNoMoreRecord = errors.New("no more record")
 	// ErrDisposed is the error that the iterator is disposed
 	ErrDisposed = errors.New("iterator is disposed")