diff --git a/internal/proxy/channels_mgr.go b/internal/proxy/channels_mgr.go
index d98b3006eb..7da4868ee1 100644
--- a/internal/proxy/channels_mgr.go
+++ b/internal/proxy/channels_mgr.go
@@ -103,6 +103,7 @@ func getDmlChannelsFunc(ctx context.Context, rc types.RootCoord) getChannelsFunc
 	}
 }
 
+// getDqlChannelsFunc returns a function about how to get query channels of a collection.
 func getDqlChannelsFunc(ctx context.Context, proxyID int64, qc createQueryChannelInterface) getChannelsFuncType {
 	return func(collectionID UniqueID) (map[vChan]pChan, error) {
 		req := &querypb.CreateQueryChannelRequest{