diff --git a/a8/mysql.cc b/a8/mysql.cc
index 1aefde4..8fc4550 100644
--- a/a8/mysql.cc
+++ b/a8/mysql.cc
@@ -80,7 +80,7 @@ namespace a8
                                       impl_->passwd.c_str(),
                                       impl_->database.c_str(),
                                       impl_->port,
-                                      NULL,
+                                      nullptr,
                                       0);
         }
 
@@ -102,6 +102,31 @@ namespace a8
             return new Query(impl_);
         }
 
+        std::string Connection::GetHost()
+        {
+            return impl_->host;
+        }
+
+        int Connection::GetPort()
+        {
+            return impl_->port;
+        }
+
+        std::string Connection::GetUser()
+        {
+            return impl_->username;
+        }
+
+        std::string Connection::GetPasswd()
+        {
+            return impl_->passwd;
+        }
+
+        std::string Connection::GetDataBase()
+        {
+            return impl_->database;
+        }
+
         Query::Query(a8::mysql::ConnectionImpl* conn_impl)
         {
             impl_ = new QueryImpl();
diff --git a/a8/mysql.h b/a8/mysql.h
index 2299d06..925cd65 100644
--- a/a8/mysql.h
+++ b/a8/mysql.h
@@ -23,6 +23,12 @@ namespace a8
             std::string GetError();
             a8::mysql::Query* CreateQuery();
 
+            std::string GetHost();
+            int GetPort();
+            std::string GetUser();
+            std::string GetPasswd();
+            std::string GetDataBase();
+
         private:
             a8::mysql::ConnectionImpl* impl_ = nullptr;
         };
diff --git a/a8/xobject.cc b/a8/xobject.cc
index de15fff..f875197 100644
--- a/a8/xobject.cc
+++ b/a8/xobject.cc
@@ -64,6 +64,68 @@ namespace a8
         }
     }
 
+    void XObject::Reset()
+    {
+        switch (type_) {
+        case a8::XOT_SIMPLE:
+            {
+            }
+            break;
+        case a8::XOT_ARRAY:
+            {
+                delete value_.array_value;
+                type_ = XOT_SIMPLE;
+                value_.x_value = new a8::XValue();
+            }
+            break;
+        case a8::XOT_OBJECT:
+            {
+                delete value_.object_value;
+                type_ = XOT_SIMPLE;
+                value_.x_value = new a8::XValue();
+            }
+            break;
+        default:
+            abort();
+        }
+    }
+
+    void XObject::DeepCopy(a8::XObject& to)
+    {
+        to.Reset();
+        switch (type_) {
+        case a8::XOT_SIMPLE:
+            {
+                value_.x_value->DeepCopy(*to.value_.x_value);
+            }
+            break;
+        case a8::XOT_ARRAY:
+            {
+                type_ = XOT_ARRAY;
+                value_.array_value = new std::vector<std::shared_ptr<a8::XObject>>();
+                for (auto& value : *value_.array_value) {
+                    std::shared_ptr<a8::XObject> xobj_ptr = std::make_shared<a8::XObject>();
+                    value->DeepCopy(*xobj_ptr.get());
+                    value_.array_value->push_back(xobj_ptr);
+                }
+            }
+            break;
+        case a8::XOT_OBJECT:
+            {
+                type_ = XOT_OBJECT;
+                value_.object_value = new std::map<std::string, std::shared_ptr<a8::XObject>>();
+                for (auto& pair : *value_.object_value) {
+                    std::shared_ptr<a8::XObject> xobj_ptr = std::make_shared<a8::XObject>();
+                    pair.second->DeepCopy(*xobj_ptr.get());
+                    (*(value_.object_value))[pair.first] = xobj_ptr;
+                }
+            }
+            break;
+        default:
+            abort();
+        }
+    }
+
     a8::XValue XObject::AsXValue()
     {
         assert(type_ == XOT_SIMPLE);
diff --git a/a8/xobject.h b/a8/xobject.h
index 61fb16a..c3cba0f 100644
--- a/a8/xobject.h
+++ b/a8/xobject.h
@@ -27,6 +27,8 @@ namespace a8
 
         unsigned char GetType();
         int Size();
+        void Reset();
+        void DeepCopy(a8::XObject& to);
 
         a8::XValue AsXValue();
         std::shared_ptr<a8::XObject> operator[] (int i);
diff --git a/a8/xparams.h b/a8/xparams.h
index 088f31e..4381d7f 100644
--- a/a8/xparams.h
+++ b/a8/xparams.h
@@ -36,6 +36,11 @@ namespace a8
             return *this;
         }
 
+        void DeepCopy(a8::XParams& to)
+        {
+            to = *this;
+        }
+
     public:
         a8::XValue sender;
         a8::XValue param1;
diff --git a/a8/xvalue.cc b/a8/xvalue.cc
index 54909f2..4d68eda 100644
--- a/a8/xvalue.cc
+++ b/a8/xvalue.cc
@@ -213,6 +213,11 @@ namespace a8
         value_.int_value = 0;
     }
 
+    void XValue::DeepCopy(a8::XValue& to)
+    {
+        to = *this;
+    }
+
     int XValue::Type() const
     {
         return type_;
@@ -311,7 +316,7 @@ namespace a8
             }
         case XVT_WSTRING:
             {
-                double dwV = 0;
+                double dwV = 0;
                 if (value_.wstr_value){
                     if (wcsstr(value_.wstr_value, L"-")){
                         assert(false);
diff --git a/a8/xvalue.h b/a8/xvalue.h
index fd2f164..cbc1fda 100644
--- a/a8/xvalue.h
+++ b/a8/xvalue.h
@@ -45,6 +45,7 @@ namespace a8
         void SetUserData(void *userdata, int datasize);
         void Set(double v);
         void SetNull();
+        void DeepCopy(a8::XValue& to);
 
         int Type() const;
         bool IsNull();