wait to be verified
diff --git a/src/db/db-mgr.cpp b/src/db/db-mgr.cpp
new file mode 100644
index 0000000..5ab9db1
--- /dev/null
+++ b/src/db/db-mgr.cpp
@@ -0,0 +1,103 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014, Regents of the University of California.
+ *
+ * This file is part of NDNS (Named Data Networking Domain Name Service).
+ * See AUTHORS.md for complete list of NDNS authors and contributors.
+ *
+ * NDNS is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NDNS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * NDNS, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <iostream>
+#include <fstream>
+
+#include "db-mgr.hpp"
+
+namespace ndn {
+namespace ndns {
+
+DBMgr::DBMgr()
+: m_dbfile("src/db/ndns-local.db")
+, m_conn(0)
+, m_reCode(-1)
+, m_status(DBClosed)
+, m_resultNum(0)
+{
+  std::fstream file;
+  file.open(m_dbfile,std::ios::in);
+  if (file)
+  {
+    std::cout<<"database file "<<m_dbfile<<" does exist"<<std::endl;
+  } else
+  {
+    std::cout<<"database file "<<m_dbfile<<" does not exist"<<std::endl;
+  }
+
+}
+
+
+DBMgr::~DBMgr()
+{
+}
+
+void DBMgr::open()
+{
+  if (m_status == DBConnected)
+    return;
+
+  m_reCode = sqlite3_open(this->m_dbfile.c_str(), &(this->m_conn));
+  if (m_reCode != SQLITE_OK)
+  {
+    m_err = "Cannot connect to the db: "+this->m_dbfile;
+    m_status = DBError;
+    //exit(1);
+  }else
+  {
+    std::cout<<"connect to the db: "<<m_dbfile<<std::endl;
+  }
+  m_status = DBConnected;
+}
+
+void DBMgr::close()
+{
+  if (m_status == DBClosed)
+    return;
+
+  m_reCode = sqlite3_close(this->m_conn);
+  if (m_reCode != SQLITE_OK)
+  {
+        m_err = "Cannot close the db: "+this->m_dbfile;
+        m_status = DBError;
+  }
+  m_status = DBClosed;
+}
+
+void DBMgr::execute(std::string sql, int (*callback)(void*,int,char**,char**), void * paras)
+{
+  if (m_status == DBClosed)
+    this->open();
+
+  clearResultNum();
+  char *err_msg;
+  m_reCode = sqlite3_exec(m_conn, sql.c_str(), callback, paras, &err_msg);
+  if (m_reCode != SQLITE_OK)
+  {
+    m_status = DBError;
+    this->m_err.append(err_msg);
+    std::cout<<this->m_err<<std::endl;
+  }
+  this->close();
+}
+
+}//namespace ndns
+}//namespace ndn
+