diff --git a/src/datanode/src/instance.rs b/src/datanode/src/instance.rs
index 884ca31e47..eb4f68ee5b 100644
--- a/src/datanode/src/instance.rs
+++ b/src/datanode/src/instance.rs
@@ -236,7 +236,6 @@ impl Instance {
             }
         };
 
-        // let factory = QueryEngineFactory::new(catalog_manager.clone(), false);
         let factory = QueryEngineFactory::new_with_plugins(
             catalog_manager.clone(),
             false,
diff --git a/src/query/src/physical_wrapper.rs b/src/query/src/physical_wrapper.rs
index af01b8984a..a1a36cf500 100644
--- a/src/query/src/physical_wrapper.rs
+++ b/src/query/src/physical_wrapper.rs
@@ -17,8 +17,8 @@ use std::sync::Arc;
 use common_query::physical_plan::PhysicalPlan;
 use session::context::QueryContextRef;
 
-/// allow physical plan to be wrapped by other physical plan
-/// e.g. add metrics to a physical plan
+/// wrap physical plan with additional logic
+/// e.g: metrics retrieving layer upon physical plan
 pub trait PhysicalWrapper: Send + Sync + 'static {
     fn wrap(&self, origin: Arc<dyn PhysicalPlan>, ctx: QueryContextRef) -> Arc<dyn PhysicalPlan>;
 }