diff --git a/src/observer/storage/common/bplus_tree.cpp b/src/observer/storage/common/bplus_tree.cpp
index df62fc86d26eb6e3ca81154fe48d32c9756e939f..ff5d313185c148f449ab035fb69a09f020d2618a 100644
--- a/src/observer/storage/common/bplus_tree.cpp
+++ b/src/observer/storage/common/bplus_tree.cpp
@@ -314,7 +314,7 @@ std::string to_string(const LeafIndexNodeHandler &handler, const KeyPrinter &pri
   ss << to_string((const IndexNodeHandler &)handler)
      << ",prev page:" << handler.prev_page()
      << ",next page:" << handler.next_page();
-  ss << ",values=[" << printer(handler.__key_at(0));
+  ss << ",values=[" << printer(handler.__key_at(0)) ;
   for (int i = 1; i < handler.size(); i++) {
     ss << "," << printer(handler.__key_at(i));
   }
diff --git a/src/observer/storage/common/bplus_tree.h b/src/observer/storage/common/bplus_tree.h
index f5090b6d55deaf2fa8a3d42321cc2b293476f935..673c44be86df6ef2df087e67c37919af5b90b51b 100644
--- a/src/observer/storage/common/bplus_tree.h
+++ b/src/observer/storage/common/bplus_tree.h
@@ -143,11 +143,12 @@ public:
   }
 
   std::string operator() (const char *v) const {
-    std::string result = attr_printer_(v);
-    result.append(",");
+    std::stringstream ss;
+    ss << "{key:" << attr_printer_(v) << ",";
 
     const RID *rid = (const RID *)(v + attr_printer_.attr_length());
-    return result.append(rid->to_string());
+    ss << "rid:{" << rid->to_string() << "}}";
+    return ss.str();
   }
 
 private: