diff --git a/cpp/src/db/DBMetaImpl.cpp b/cpp/src/db/DBMetaImpl.cpp
index 56b02b77526a407996654c3a6f7257435122833e..9e988f61be88f142ad5a2ecec26c38f783278a00 100644
--- a/cpp/src/db/DBMetaImpl.cpp
+++ b/cpp/src/db/DBMetaImpl.cpp
@@ -5,7 +5,7 @@
 #include <boost/filesystem.hpp>
 #include <chrono>
 #include <fstream>
-#include <sqlite_orm/sqlite_orm.h>
+#include <sqlite_orm.h>
 #include <easylogging++.h>
 #include "DBMetaImpl.h"
 #include "IDGenerator.h"
@@ -88,6 +88,7 @@ Status DBMetaImpl::initialize() {
 
     ConnectorPtr->sync_schema();
     ConnectorPtr->open_forever(); // thread safe option
+    ConnectorPtr->pragma.journal_mode(journal_mode::WAL); // WAL => write ahead log
 
     cleanup();
 
diff --git a/cpp/src/db/db_connection.h b/cpp/src/db/db_connection.h
index ecc55790f3fc38bf6cc7d52aa53ef84c88592314..cfd34461af00038ae4504ba6d70a82ff297b17bc 100644
--- a/cpp/src/db/db_connection.h
+++ b/cpp/src/db/db_connection.h
@@ -9,7 +9,7 @@
 #include <string>
 #include <memory>
 
-#include <sqlite_orm/sqlite_orm.h>
+#include <sqlite_orm.h>
 
 
 namespace zilliz {
@@ -62,7 +62,3 @@ class Connection {
 }
 }
 }
-
-
-
-