diff --git a/admin/adduser.php b/admin/adduser.php
index da08217a..5efcac71 100644
--- a/admin/adduser.php
+++ b/admin/adduser.php
@@ -3,12 +3,12 @@
  * @Author: printempw
  * @Date:   2016-03-19 21:00:58
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-26 21:44:04
+ * @Last Modified time: 2016-04-02 18:33:01
  */
 require "../libraries/session.inc.php";
 if (!$user->is_admin) header('Location: ../index.php?msg=看起来你并不是管理员');
 View::show('admin/header', array('page_title' => "添加用户"));
-$db = new Database\Database();
+$db = new Database\Database('users');
 ?>
 <!-- Content Wrapper. Contains page content -->
 <div class="content-wrapper">
diff --git a/admin/customize.php b/admin/customize.php
index b8fc6bdb..183a3c72 100644
--- a/admin/customize.php
+++ b/admin/customize.php
@@ -3,7 +3,7 @@
  * @Author: printempw
  * @Date:   2016-03-19 14:34:21
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-26 22:28:23
+ * @Last Modified time: 2016-04-02 18:33:01
  */
 require "../libraries/session.inc.php";
 if (!$user->is_admin) header('Location: ../index.php?msg=看起来你并不是管理员');
@@ -17,7 +17,7 @@ $data['style'] = <<< 'EOT'
 EOT;
 $data['page_title'] = "个性化";
 View::show('admin/header', $data);
-$db = new Database\Database();
+$db = new Database\Database('users');
 ?>
 <!-- Content Wrapper. Contains page content -->
 <div class="content-wrapper">
diff --git a/admin/index.php b/admin/index.php
index 5c07feb8..b623c5e5 100644
--- a/admin/index.php
+++ b/admin/index.php
@@ -3,12 +3,12 @@
  * @Author: printempw
  * @Date:   2016-02-03 14:39:50
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-26 20:06:00
+ * @Last Modified time: 2016-04-02 18:33:02
  */
 require "../libraries/session.inc.php";
 if (!$user->is_admin) header('Location: ../index.php?msg=看起来你并不是管理员');
 View::show('admin/header', array('page_title' => "仪表盘"));
-$db = new Database\Database();
+$db = new Database\Database('users');
 ?>
 <!-- Content Wrapper. Contains page content -->
 <div class="content-wrapper">
diff --git a/admin/manage.php b/admin/manage.php
index 781c79a2..3dc42942 100644
--- a/admin/manage.php
+++ b/admin/manage.php
@@ -3,12 +3,12 @@
  * @Author: printempw
  * @Date:   2016-03-06 14:19:20
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-27 10:53:06
+ * @Last Modified time: 2016-04-02 18:33:02
  */
 require "../libraries/session.inc.php";
 if (!$user->is_admin) header('Location: ../index.php?msg=看起来你并不是管理员');
 View::show('admin/header', array('page_title' => "用户管理"));
-$db = new Database\Database();
+$db = new Database\Database('users');
 
 if (isset($_GET['show'])) {
     View::show('admin/show', ['uid' => (int)$_GET['show']]);
diff --git a/admin/options.php b/admin/options.php
index b55d59d5..b696be81 100644
--- a/admin/options.php
+++ b/admin/options.php
@@ -3,12 +3,12 @@
  * @Author: printempw
  * @Date:   2016-03-18 22:50:25
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-26 22:28:23
+ * @Last Modified time: 2016-04-02 18:33:02
  */
 require "../libraries/session.inc.php";
 if (!$user->is_admin) header('Location: ../index.php?msg=看起来你并不是管理员');
 View::show('admin/header', array('page_title' => "站点配置"));
-$db = new Database\Database();
+$db = new Database\Database('users');
 ?>
 <!-- Content Wrapper. Contains page content -->
 <div class="content-wrapper">
diff --git a/admin/update.php b/admin/update.php
index 399dd06c..43854db2 100644
--- a/admin/update.php
+++ b/admin/update.php
@@ -3,12 +3,12 @@
  * @Author: printempw
  * @Date:   2016-03-27 15:03:40
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-27 16:15:17
+ * @Last Modified time: 2016-04-02 18:33:02
  */
 require "../libraries/session.inc.php";
 if (!$user->is_admin) header('Location: ../index.php?msg=看起来你并不是管理员');
 View::show('admin/header', array('page_title' => "检查更新"));
-$db = new Database\Database();
+$db = new Database\Database('users');
 ?>
 <!-- Content Wrapper. Contains page content -->
 <div class="content-wrapper">
diff --git a/libraries/Database/AdaptedDatabase.class.php b/libraries/Database/AdaptedDatabase.class.php
index 33fa0651..4e650891 100644
--- a/libraries/Database/AdaptedDatabase.class.php
+++ b/libraries/Database/AdaptedDatabase.class.php
@@ -3,7 +3,7 @@
  * @Author: printempw
  * @Date:   2016-03-18 16:53:55
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-04-02 18:13:50
+ * @Last Modified time: 2016-04-02 22:14:12
  */
 
 namespace Database;
@@ -15,59 +15,66 @@ use Option;
 
 class AdaptedDatabase extends Database implements EncryptInterface, SyncInterface
 {
-    protected $table_name;
+    protected $data_table;
     protected $column_uname;
     protected $column_passwd;
     protected $column_ip;
 
-    function __construct() {
-        parent::__construct();
-        $this->table_name    = Option::get('data_table_name');
+    function __construct($table_name = '') {
+        parent::__construct($table_name);
+        $this->data_table    = Option::get('data_table_name');
         $this->column_uname  = Option::get('data_column_uname');
         $this->column_passwd = Option::get('data_column_passwd');
         $this->column_ip     = Option::get('data_column_ip');
     }
 
-    public function createRecord($username, $password, $ip) {
-        $sql = "INSERT INTO ".$this->table_name." (".$this->column_uname.", ".$this->column_passwd.", ".$this->column_ip.")
-                VALUES ('$username', '$password', '$ip')";
-        return $this->query($sql);
-    }
-
-    public function sync($username) {
-        $exist_in_bs_table = $this->checkRecordExist('username', $username);
-        $exist_in_data_table = ($this->query("SELECT * FROM ".$this->table_name."
-            WHERE ".$this->column_uname."='$username'")->num_rows) ? true : false;
+    public function sync($username, $reverse = false) {
+        $exist_in_bs_table   = $this->has('username', $username);
+        $exist_in_data_table = $this->has($this->column_uname, $username, $this->data_table);
 
         if ($exist_in_bs_table && !$exist_in_data_table) {
             $result = $this->select('username', $username);
-            $this->createRecord($username, $result['password'], $result['ip']);
+
+            $this->insert(array(
+                $this->column_uname => $username,
+                $this->column_passwd => $result['password'],
+                $this->column_ip => $result['ip']
+            ), $this->data_table);
+
+            // recursion
             return $this->sync($username);
         }
 
         if (!$exist_in_bs_table && $exist_in_data_table) {
-            $result = $this->query("SELECT * FROM ".$this->table_name."
-                WHERE ".$this->column_uname."='$username'")->fetch_array();
+            $result = $this->select($this->column_uname, $username, null, $this->data_table);
+
             $this->insert(array(
-                                "uname" => $username,
-                                "passwd" => $result[$this->column_passwd],
-                                "ip" => $result[$this->column_ip]
-                            ));
+                "username" => $username,
+                "password" => $result[$this->column_passwd],
+                "ip"       => $result[$this->column_ip]
+            ));
+
+            // recursion
             return $this->sync($username);
         }
 
         if (!($exist_in_bs_table || $exist_in_data_table))
+            // user not exists
             return false;
 
         if ($exist_in_bs_table && $exist_in_data_table) {
             $passwd1 = $this->select('username', $username)['password'];
-            $passwd2 = $this->query("SELECT * FROM ".$this->table_name."
-                WHERE ".$this->column_uname."='$username'")->fetch_array()[$this->column_passwd];
+            $passwd2 = $this->select($this->column_uname, $username, null, $this->data_table)[$this->column_passwd];
+
             if ($passwd1 == $passwd2) {
                 return true;
             } else {
                 // sync password
-                $this->update($username, 'password', $passwd2);
+                if ($reverse) {
+                    $this->update($this->column_passwd, $passwd1, ['where' => "$this->column_uname='$username'"], $this->data_table);
+                } else {
+                    $this->update('password', $passwd2, ['where' => "username='$username'"]);
+                }
                 return $this->sync($username);
             }
         }
diff --git a/libraries/Database/AuthmeDatabase.class.php b/libraries/Database/AuthmeDatabase.class.php
index 728f8001..a2911b9b 100644
--- a/libraries/Database/AuthmeDatabase.class.php
+++ b/libraries/Database/AuthmeDatabase.class.php
@@ -3,7 +3,7 @@
  * @Author: printempw
  * @Date:   2016-03-13 11:59:32
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-27 12:32:25
+ * @Last Modified time: 2016-04-02 22:03:39
  */
 
 namespace Database;
@@ -12,13 +12,19 @@ use Database\AdaptedDatabase;
 
 class AuthmeDatabase extends AdaptedDatabase
 {
+
     /**
      * Default SHA256 encryption method for Authme
      *
      * @see http://pastebin.com/1wy9g2HT
      */
     public function encryptPassword($raw_passwd, $username="") {
-        $salt = $this->getPwdInfo($username)['salt'];
+        if ($this->has('username', $username)) {
+            $salt = $this->getPwdInfo($username)['salt'];
+        } else {
+            // generate random salt
+            $salt = \Utils::generateRndString(16);
+        }
         $hash = hash('sha256', hash('sha256', $raw_passwd).$salt);
         $encrypt = '$SHA$'.$salt.'$'. $hash;
         return $encrypt;
@@ -32,8 +38,7 @@ class AuthmeDatabase extends AdaptedDatabase
      * @return array
      */
     private function getPwdInfo($username) {
-        $hashed = $this->query("SELECT * FROM ".$this->table_name."
-            WHERE ".$this->column_uname."='$username'")->fetch_array()['password'];
+        $hashed = $this->select($this->column_uname, $username)['password'];
         $parts = explode('$', $hashed);
         $pwd_info['password'] = $parts[3];
         $pwd_info['salt'] = $parts[2];
diff --git a/libraries/Database/Database.class.php b/libraries/Database/Database.class.php
index 831b6970..0b386a7d 100644
--- a/libraries/Database/Database.class.php
+++ b/libraries/Database/Database.class.php
@@ -3,39 +3,36 @@
  * @Author: printempw
  * @Date:   2016-02-02 21:59:06
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-27 14:50:39
+ * @Last Modified time: 2016-04-02 22:50:41
  */
 
 namespace Database;
 
-use Database\EncryptInterface;
-use Database\SyncInterface;
 use Utils;
-use Mysqli;
 use E;
 
 class Database implements EncryptInterface, SyncInterface
 {
     private $connection = null;
 
-    function __construct() {
-        $this->connection = self::checkConfig();
-    }
+    private $table_name = "";
 
-    function __destruct() {
-        $this->connection->close();
+    function __construct($table_name = '') {
+        $this->connection = self::checkConfig();
+        $this->table_name = DB_PREFIX.$table_name;
     }
 
     public static function checkConfig() {
         // use error control to hide shitty connect warnings
-        error_reporting(0);
-        $conn = new mysqli(DB_HOST, DB_USER, DB_PASSWD, DB_NAME, DB_PORT);
-        error_reporting(E_ALL ^ E_NOTICE);
+        @$conn = new \mysqli(DB_HOST, DB_USER, DB_PASSWD, DB_NAME, DB_PORT);
 
         if ($conn->connect_error)
             throw new E("无法连接至 MySQL 服务器。请确认 config.php 中的配置是否正确：".$conn->connect_error, $conn->connect_errno, true);
-        if (!self::checkTableExist($conn))
+
+        $sql = "SELECT table_name FROM `INFORMATION_SCHEMA`.`TABLES` WHERE (table_name ='".DB_PREFIX."users'OR table_name ='".DB_PREFIX."options') AND TABLE_SCHEMA='".DB_NAME."'";
+        if ($conn->query($sql)->num_rows != 2)
             throw new E("数据库中不存在 ".DB_PREFIX."users 或 ".DB_PREFIX."options 表。请先访问 <a href='./setup'>/setup</a> 进行安装。", -1, true);
+
         if (!is_dir(BASE_DIR."/textures/"))
             throw new E("textures 文件夹不存在。请先访问 <a href='./setup'>/setup</a> 进行安装，或者手动放置一个。", -1, true);
 
@@ -43,70 +40,120 @@ class Database implements EncryptInterface, SyncInterface
         return $conn;
     }
 
-    public static function checkTableExist($conn) {
-        $sql = "SELECT table_name FROM
-                `INFORMATION_SCHEMA`.`TABLES` WHERE (table_name ='".DB_PREFIX."users'
-                OR table_name ='".DB_PREFIX."options') AND TABLE_SCHEMA='".DB_NAME."'";
-
-        if ($conn->query($sql)->num_rows != 2)
-            return false;
-        return true;
-    }
-
     public function query($sql) {
         $result = $this->connection->query($sql);
-        if (!$this->connection->error) {
-            return $result;
-        }
-        throw new E("Database query error: ".$this->connection->error, -1);
+        if ($this->connection->error)
+            throw new E("Database query error: ".$this->connection->error.", Statement: ".$sql, -1);
+        return $result;
     }
 
     public function fetchArray($sql) {
         return $this->query($sql)->fetch_array();
     }
 
-    public function select($key, $value) {
-        return $this->fetchArray("SELECT * FROM ".DB_PREFIX."users WHERE $key='$value'");
+    /**
+     * Select records from table
+     *
+     * @param  string  $key
+     * @param  string  $value
+     * @param  array   $condition, see function `where`
+     * @param  string  $table, which table to operate
+     * @param  boolean $dont_fetch_array, return resources if true
+     * @return array|resources
+     */
+    public function select($key, $value, $condition = null, $table = null, $dont_fetch_array = false) {
+        $table = is_null($table) ? $this->table_name : $table;
+
+        if (isset($condition['where'])) {
+            $sql = "SELECT * FROM $table".$this->where($condition);
+        } else {
+            $sql = "SELECT * FROM $table WHERE $key='$value'";
+        }
+
+        if ($dont_fetch_array) {
+            return $this->query($sql);
+        } else {
+            return $this->fetchArray($sql);
+        }
+
     }
 
-    public function getNumRows($key, $value) {
-        $sql = "SELECT * FROM ".DB_PREFIX."users WHERE $key='$value'";
-        return $this->query($sql)->num_rows;
+    public function has($key, $value, $table = null) {
+        return ($this->getNumRows($key, $value, $table) != 0) ? true : false;
     }
 
-    public function getRecordNum() {
-        $sql = "SELECT * FROM ".DB_PREFIX."users WHERE 1";
-        return $this->query($sql)->num_rows;
-    }
+    public function insert($data, $table = null) {
+        $keys   = "";
+        $values = "";
+        $table  = is_null($table) ? $this->table_name : $table;
 
-    public function checkRecordExist($key, $value) {
-        return ($this->getNumRows($key, $value) != 0) ? true : false;
-    }
+        foreach($data as $key => $value) {
+            if ($value == end($data)) {
+                $keys .= '`'.$key.'`';
+                $values .= '"'.$value.'"';
+            } else {
+                $keys .= '`'.$key.'`,';
+                $values .= '"'.$value.'", ';
+            }
+        }
 
-    public function insert($array) {
-        $uname  = $array['uname'];
-        $passwd = $array['passwd'];
-        $ip = $array['ip'];
-        $sql = "INSERT INTO ".DB_PREFIX."users (username, password, ip, preference)
-                                            VALUES ('$uname', '$passwd', '$ip', 'default')";
+        $sql = "INSERT INTO $table ({$keys}) VALUES ($values)";
         return $this->query($sql);
     }
 
-    public function update($uname, $key, $value) {
-        return $this->query("UPDATE ".DB_PREFIX."users SET `$key`='$value' WHERE username='$uname'");
+    public function update($key, $value, $condition = null, $table = null) {
+        $table = is_null($table) ? $this->table_name : $table;
+        return $this->query("UPDATE $table SET `$key`='$value'".$this->where($condition));
     }
 
-    public function delete($uname) {
-        return $this->query("DELETE FROM ".DB_PREFIX."users WHERE username='$uname'");
+    public function delete($condition = null, $table = null) {
+        $table = is_null($table) ? $this->table_name : $table;
+        return $this->query("DELETE FROM $table".$this->where($condition));
     }
 
-    public function encryptPassword($raw_passwd, $username="") {
+    public function getNumRows($key, $value, $table = null) {
+        $table = is_null($table) ? $this->table_name : $table;
+        $sql = "SELECT * FROM $table WHERE $key='$value'";
+        return $this->query($sql)->num_rows;
+    }
+
+    public function getRecordNum($table = null) {
+        $table = is_null($table) ? $this->table_name : $table;
+        $sql = "SELECT * FROM $table WHERE 1";
+        return $this->query($sql)->num_rows;
+    }
+
+    public function encryptPassword($raw_passwd, $username = "") {
         $encrypt = md5($raw_passwd);
         return $encrypt;
     }
 
-    public function sync($username) {
-        return ($this->checkRecordExist('username', $username)) ? true : false;
+    public function sync($username, $reverse = false) {
+        return ($this->has('username', $username)) ? true : false;
+    }
+
+    /**
+     * Generate where statement
+     *
+     * @param  array $condition, e.g. array('where'=>'username="shit"', 'limit'=>10, 'order'=>'uid')
+     * @return string
+     */
+    private function where($condition) {
+        $statement = "";
+        if (isset($condition['where']) && $condition['where'] != "") {
+            $statement .= ' WHERE '.$condition['where'];
+        }
+        if (isset($condition['order'])) {
+            $statement .= ' ORDER BY `'.$condition['order'].'`';
+        }
+        if (isset($condition['limit'])) {
+            $statement .= ' LIMIT '.$condition['limit'];
+        }
+        return $statement;
+    }
+
+    function __destruct() {
+        $this->connection->close();
     }
 
 }
diff --git a/libraries/Database/SyncInterface.class.php b/libraries/Database/SyncInterface.class.php
index c136d010..0995493b 100644
--- a/libraries/Database/SyncInterface.class.php
+++ b/libraries/Database/SyncInterface.class.php
@@ -3,7 +3,7 @@
  * @Author: printempw
  * @Date:   2016-03-13 13:31:28
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-18 17:23:33
+ * @Last Modified time: 2016-04-02 21:36:09
  */
 
 namespace Database;
@@ -16,6 +16,6 @@ interface SyncInterface
      * @param  string $username, unique identifier of each record
      * @return bool
      */
-    public function sync($username);
+    public function sync($username, $reverse = false);
 
 }
diff --git a/libraries/E.class.php b/libraries/E.class.php
index cf97a2cb..cdf5787e 100644
--- a/libraries/E.class.php
+++ b/libraries/E.class.php
@@ -3,7 +3,7 @@
  * @Author: printempw
  * @Date:   2016-03-27 11:04:14
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-27 11:36:57
+ * @Last Modified time: 2016-04-02 22:25:08
  */
 
 class E extends Exception
@@ -27,7 +27,7 @@ class E extends Exception
     private function showErrorJson() {
         $exception['errno'] = $this->code;
         $exception['msg'] = $this->message;
-        header('Content-type: application/json; charset=utf-8');
+        @header('Content-type: application/json; charset=utf-8');
         exit(json_encode($exception));
     }
 
diff --git a/libraries/Option.class.php b/libraries/Option.class.php
index ac7663a5..be844192 100644
--- a/libraries/Option.class.php
+++ b/libraries/Option.class.php
@@ -3,7 +3,7 @@
  * @Author: printempw
  * @Date:   2016-03-18 14:02:12
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-27 11:28:24
+ * @Last Modified time: 2016-04-02 22:50:19
  */
 
 use Database\Database;
@@ -11,72 +11,37 @@ use Database\Database;
 class Option
 {
     public static function get($key) {
-        $conn = Database::checkConfig();
-        $sql = "SELECT * FROM ".DB_PREFIX."options WHERE `option_name` = '$key'";
-        $result = $conn->query($sql);
-        if ($conn->error)
-            throw new E("Database query error: ".$conn->error, -1);
-        return $result->fetch_array()['option_value'];
+        $db = new Database('options');
+        $result = $db->select('option_name', $key);
+        return $result['option_value'];
     }
 
     public static function set($key, $value) {
-        $conn = Database::checkConfig();
+        $db = new Database('options');
         if (!self::has($key)) {
             self::add($key, $value);
         } else {
-            $sql = "UPDATE ".DB_PREFIX."options SET `option_value`='$value' WHERE `option_name`='$key'";
-            $result = $conn->query($sql);
-            if ($conn->error)
-                throw new E("Database query error: ".$conn->error, -1);
-            else
-                return true;
+            return $db->update('option_value', $value, ['where' => "option_name='$key'"]);
         }
     }
 
     public static function add($key, $value) {
-        $conn = Database::checkConfig();
-        // check if option exists
-        if (!self::has($key)) {
-            $sql = "INSERT INTO ".DB_PREFIX."options (`option_name`, `option_value`) VALUES ('$key', '$value')";
-            $result = $conn->query($sql);
-            if ($conn->error)
-                throw new E("Database query error: ".$conn->error, -1);
-            else
-                return true;
-        } else {
-            return true;
-        }
+        $db = new Database('options');
+        return $db->insert(['option_name' => $key, 'option_value' => $value]);
     }
 
     public static function has($key) {
-        $conn = Database::checkConfig();
-        // check if option exists
-        $sql = "SELECT * FROM ".DB_PREFIX."options WHERE `option_name` = '$key'";
-        if ($conn->query($sql)->num_rows != 0) {
-            return true;
-        } else {
-            return false;
-        }
+        $db = new Database('options');
+        return $db->has('option_name', $key);
     }
 
     public static function delete($key) {
-        $conn = Database::checkConfig();
+        $db = new Database('options');
         if (self::has($key)) {
-            $sql = "DELETE FROM ".DB_PREFIX."options WHERE `option_name`='$key'";
-            $result = $conn->query($sql);
-            if ($conn->error)
-                throw new E("Database query error: ".$conn->error, -1);
-            else
-                return true;
+            return $db->delete(['where' => "option_name='$key'"]);
         } else {
             return false;
         }
     }
 
-    public static function setArray($options) {
-        foreach ($options as $key => $value) {
-            self::set($key, $value);
-        }
-        return true;
-    }
 }
diff --git a/libraries/User.class.php b/libraries/User.class.php
index 8dfbbdc7..273a1aad 100644
--- a/libraries/User.class.php
+++ b/libraries/User.class.php
@@ -3,7 +3,7 @@
  * @Author: printempw
  * @Date:   2016-01-16 23:01:33
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-27 11:44:48
+ * @Last Modified time: 2016-04-02 22:50:16
  */
 
 use Database\Database;
@@ -21,7 +21,7 @@ class User
     function __construct($uname) {
         $this->uname = Utils::convertString($uname);
         $class_name = "Database\\".Option::get('data_adapter')."Database";
-        $this->db = new $class_name();
+        $this->db = new $class_name('users');
 
         if ($this->db->sync($this->uname)) {
             $this->passwd = $this->db->select('username', $this->uname)['password'];
@@ -55,7 +55,8 @@ class User
     }
 
     public function changePasswd($new_passwd) {
-        $this->db->update($this->uname, 'password', $this->db->encryptPassword($new_passwd, $this->uname));
+        $this->db->update('password', $this->db->encryptPassword($new_passwd, $this->uname), ['where' => "username='$this->uname'"]);
+        $this->db->sync($this->uname, true);
     }
 
     public function getToken() {
@@ -63,11 +64,13 @@ class User
     }
 
     public function register($passwd, $ip) {
-        return $this->db->insert(array(
-                                        "uname" => $this->uname,
-                                        "passwd" => $this->db->encryptPassword($passwd),
-                                        "ip" => $ip
-                                    ));
+        $data = array(
+                    "username"   => $this->uname,
+                    "password"   => $this->db->encryptPassword($passwd),
+                    "ip"         => $ip,
+                    "preference" => 'default'
+                );
+        return $this->db->insert($data);
     }
 
     public function unRegister() {
@@ -76,7 +79,7 @@ class User
             if ($this->getTexture($skin_type_map[$i]) != "" && !Utils::checkTextureOccupied($this->getTexture($skin_type_map[$i])))
                 Utils::remove("./textures/".$this->getTexture($skin_type_map[$i]));
         }
-        return $this->db->delete($this->uname);
+        return $this->db->delete(['where' => "username='$this->uname'"]);
     }
 
     public function reset() {
@@ -84,9 +87,9 @@ class User
         for ($i = 0; $i <= 2; $i++) {
             if ($this->getTexture($skin_type_map[$i]) != "" && !Utils::checkTextureOccupied($this->getTexture($skin_type_map[$i])))
                 Utils::remove("./textures/".$this->getTexture($skin_type_map[$i]));
-            $this->db->update($this->uname, 'hash_'.$skin_type_map[$i], '');
+            $this->db->update('hash_'.$skin_type_map[$i], '', ['where' => "username='$this->uname'"]);
         }
-        return $this->db->update($this->uname, 'preference', 'default');
+        return $this->db->update('preference', 'default', ['where' => "username='$this->uname'"]);
     }
 
     /**
@@ -104,7 +107,7 @@ class User
 
     public function getBinaryTexture($type) {
         if ($this->getTexture($type) != "") {
-            $filename = "./textures/".$this->getTexture($type);
+            $filename = BASE_DIR."/textures/".$this->getTexture($type);
             if (file_exists($filename)) {
                 header('Content-Type: image/png');
                 // Cache friendly
@@ -150,7 +153,7 @@ class User
         $this->updateLastModified();
         $hash = Utils::upload($file);
         if ($type == "steve" | $type == "alex" | $type == "cape")
-            return $this->db->update($this->uname, 'hash_'.$type, $hash);
+            return $this->db->update('hash_'.$type, $hash, ['where' => "username='$this->uname'"]);
         return false;
     }
 
@@ -159,7 +162,7 @@ class User
      * @param string $type, 'slim' or 'default'
      */
     public function setPreference($type) {
-        return $this->db->update($this->uname, 'preference', $type);
+        return $this->db->update('preference', $type, ['where' => "username='$this->uname'"]);
     }
 
     public function getPreference() {
@@ -200,9 +203,9 @@ class User
         return json_encode($json, JSON_PRETTY_PRINT);
     }
 
-    public function updateLastModified() {
+    public function updateLastModified() {//$this->uname
         // @see http://stackoverflow.com/questions/2215354/php-date-format-when-inserting-into-datetime-in-mysql
-        return $this->db->update($this->uname, 'last_modified', date("Y-m-d H:i:s"));
+        return $this->db->update('last_modified', date("Y-m-d H:i:s"), ['where' => "username='$this->uname'"]);
     }
 
     /**
diff --git a/libraries/Utils.class.php b/libraries/Utils.class.php
index 7d3c7a17..d9614c5d 100644
--- a/libraries/Utils.class.php
+++ b/libraries/Utils.class.php
@@ -3,7 +3,7 @@
  * @Author: printempw
  * @Date:   2016-01-16 23:01:33
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-27 11:33:59
+ * @Last Modified time: 2016-04-02 22:01:48
  */
 
 class Utils
@@ -151,7 +151,7 @@ class Utils
      * @return bool
      */
     public static function checkTextureOccupied($hash) {
-        $db = new Database\Database();
+        $db = new Database\Database('users');
         if ($db->getNumRows('hash_steve', $hash) > 1) {
             return true;
         } elseif ($db->getNumRows('hash_alex', $hash) > 1) {
@@ -163,4 +163,13 @@ class Utils
         return false;
     }
 
+    public function generateRndString($length) {
+        $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()-_ []{}<>~`+=,.;:/?|';
+        $rnd_string = '';
+        for ($i = 0; $i < $length; $i++) {
+            $rnd_string .= $chars[mt_rand(0, strlen($chars) - 1)];
+        }
+        return $rnd_string;
+    }
+
 }
diff --git a/libraries/autoloader.php b/libraries/autoloader.php
index d0590e24..aa17eadf 100644
--- a/libraries/autoloader.php
+++ b/libraries/autoloader.php
@@ -3,7 +3,7 @@
  * @Author: printempw
  * @Date:   2016-02-02 21:17:59
  * @Last Modified by:   printempw
- * @Last Modified time: 2016-03-27 11:19:58
+ * @Last Modified time: 2016-04-02 19:19:48
  */
 
 function __autoload($classname) {
@@ -11,6 +11,8 @@ function __autoload($classname) {
     // echo $classname.'<br />';
     $include_dir = $dir.DIRECTORY_SEPARATOR."libraries".DIRECTORY_SEPARATOR;
     $filename = $include_dir.str_replace('\\', DIRECTORY_SEPARATOR, $classname) . '.class.php';
+    if (!file_exists($filename))
+        exit("Undefined class `$classname` @ `$filename`");
     require_once($filename);
 }
 if (!file_exists($dir.'/config.php'))
diff --git a/templates/admin/list.tpl.php b/templates/admin/list.tpl.php
index 365d53c9..000fc97b 100644
--- a/templates/admin/list.tpl.php
+++ b/templates/admin/list.tpl.php
@@ -29,14 +29,22 @@
                     <tbody>
                         <?php
                         $page_now = isset($_GET['page']) ? $_GET['page'] : 1;
-                        $db = new Database\Database();
+                        $db = new Database\Database('users');
 
                         if (isset($_POST['search-username'])) {
-                            $result = $db->query("SELECT * FROM ".DB_PREFIX."users WHERE `username` LIKE '%".$_POST['search-username']."%' ORDER BY `uid` LIMIT ".(string)(($page_now-1)*30).", 30");
+                            $result = $db->select(null, null, [
+                                'where' => "`username` LIKE '%".$_POST['search-username']."%'",
+                                'order' => 'uid',
+                                'limit' => (string)(($page_now-1)*30).", 30"
+                            ]);
                             $page_total = round($db->query("SELECT * FROM ".DB_PREFIX."users WHERE `username` LIKE '%".$_POST['search-username']."%'")->num_rows/30);
                         } else {
-                            $result = $db->query("SELECT * FROM ".DB_PREFIX."users ORDER BY `uid` LIMIT ".(string)(($page_now-1)*30).", 30");
-                            $page_total = round($db->query("SELECT * FROM ".DB_PREFIX."users WHERE 1")->num_rows/30);
+                            $result = $db->select(null, null, [
+                                'where' => '',
+                                'order' => 'uid',
+                                'limit' => (string)(($page_now-1)*30).", 30"
+                            ], null, true);
+                            $page_total = round($db->getRecordNum()/30);
                         }
 
                         while ($row = $result->fetch_array()) { ?>
diff --git a/templates/admin/show.tpl.php b/templates/admin/show.tpl.php
index 21341894..d6e810e6 100644
--- a/templates/admin/show.tpl.php
+++ b/templates/admin/show.tpl.php
@@ -7,7 +7,7 @@
             <small>User Preview</small>
         </h1>
     </section>
-    <?php $db = new Database\Database();
+    <?php $db = new Database\Database('users');
         $user = new User($db->select('uid', $data['uid'])['username']);
     ?>
     <!-- Main content -->