diff --git a/MysqliDb.php b/MysqliDb.php
index 3682d2cd..8f0a7117 100644
--- a/MysqliDb.php
+++ b/MysqliDb.php
@@ -1,4 +1,5 @@
 <?php
+
 /**
  * MysqliDb Class
  *
@@ -11,71 +12,83 @@
  * @license   http://opensource.org/licenses/gpl-3.0.html GNU Public License
  * @link      http://github.com/joshcam/PHP-MySQLi-Database-Class 
  * @version   2.6-master
- **/
+ */
 class MysqliDb
 {
+
     /**
      * Static instance of self
      *
      * @var MysqliDb
      */
     protected static $_instance;
+
     /**
      * Table prefix
      *
      * @var string
      */
     public static $prefix = '';
+
     /**
      * MySQLi instance
      *
      * @var mysqli
      */
     protected $_mysqli;
+
     /**
      * The SQL query to be prepared and executed
      *
      * @var string
      */
     protected $_query;
+
     /**
      * The previously executed SQL query
      *
      * @var string
      */
     protected $_lastQuery;
+
     /**
      * The SQL query options required after SELECT, INSERT, UPDATE or DELETE
      *
      * @var string
      */
     protected $_queryOptions = array();
+
     /**
      * An array that holds where joins
      *
      * @var array
      */
     protected $_join = array();
+
     /**
      * An array that holds where conditions
      *
      * @var array
      */
     protected $_where = array();
+
     /**
      * An array that holds having conditions
      *
      * @var array
      */
     protected $_having = array();
+
     /**
      * Dynamic type list for order by condition value
      */
     protected $_orderBy = array();
+
     /**
      * Dynamic type list for group by condition value
      */
     protected $_groupBy = array();
+
     /**
      * Dynamic array that holds a combination of where condition/table data value types and parameter references
      *
@@ -88,12 +101,14 @@ class MysqliDb
      * @var string
      */
     public $count = 0;
+
     /**
      * Variable which holds an amount of returned rows during get/getOne/select queries with withTotalCount()
      *
      * @var string
      */
     public $totalCount = 0;
+
     /**
      * Variable which holds last statement error
      *
@@ -180,20 +195,22 @@ class MysqliDb
      * @param string $db
      * @param int $port
      */
-    public function __construct($host = NULL, $username = NULL, $password = NULL, $db = NULL, $port = NULL, $charset = 'utf8')
+    public function __construct($host = null, $username = null, $password = null, $db = null, $port = null, $charset = 'utf8')
     {
         $isSubQuery = false;
 
         // if params were passed as array
-        if (is_array ($host)) {
-            foreach ($host as $key => $val)
+        if (is_array($host)) {
+            foreach ($host as $key => $val) {
                 $$key = $val;
+            }
         }
         // if host were set as mysqli socket
-        if (is_object ($host))
+        if (is_object($host)) {
             $this->_mysqli = $host;
-        else
+        } else {
             $this->host = $host;
+        }
 
         $this->username = $username;
         $this->password = $password;
@@ -205,38 +222,48 @@ public function __construct($host = NULL, $username = NULL, $password = NULL, $d
             $this->isSubQuery = true;
             return;
         }
-        if (isset ($prefix))
-            $this->setPrefix ($prefix);
+
+        if (isset($prefix)) {
+            $this->setPrefix($prefix);
+        }
+
         self::$_instance = $this;
     }
 
     /**
      * A method to connect to the database
-     *
+     * 
+     * @throws Exception
      */
     public function connect()
     {
-        if ($this->isSubQuery)
+        if ($this->isSubQuery) {
             return;
+        }
 
-        if (empty ($this->host))
-            die ('Mysql host is not set');
+        if (empty($this->host)) {
+            throw new Exception('Mysql host is not set');
+        }
+
+        $this->_mysqli = new mysqli($this->host, $this->username, $this->password, $this->db, $this->port);
 
-        $this->_mysqli = new mysqli ($this->host, $this->username, $this->password, $this->db, $this->port);
-        if ($this->_mysqli->connect_error)
-            throw new Exception ('Connect Error ' . $this->_mysqli->connect_errno . ': ' . $this->_mysqli->connect_error);
+        if ($this->_mysqli->connect_error) {
+            throw new Exception('Connect Error ' . $this->_mysqli->connect_errno . ': ' . $this->_mysqli->connect_error);
+        }
 
-        if ($this->charset)
-            $this->_mysqli->set_charset ($this->charset);
+        if ($this->charset) {
+            $this->_mysqli->set_charset($this->charset);
+        }
     }
 
     /**
      * A method to get mysqli object or create it in case needed
      */
-    public function mysqli ()
+    public function mysqli()
     {
-        if (!$this->_mysqli)
+        if (!$this->_mysqli) {
             $this->connect();
+        }
         return $this->_mysqli;
     }
 
@@ -261,8 +288,9 @@ public static function getInstance()
      */
     protected function reset()
     {
-        if ($this->traceEnabled)
-            $this->trace[] = array ($this->_lastQuery, (microtime(true) - $this->traceStartQ) , $this->_traceGetCaller());
+        if ($this->traceEnabled) {
+            $this->trace[] = array($this->_lastQuery, (microtime(true) - $this->traceStartQ), $this->_traceGetCaller());
+        }
 
         $this->_where = array();
         $this->_having = array();
@@ -285,9 +313,10 @@ protected function reset()
     /**
      * Helper function to create dbObject with Json return type
      *
-     * @return dbObject
+     * @return object
      */
-    public function JsonBuilder () {
+    public function JsonBuilder()
+    {
         $this->returnType = 'Json';
         return $this;
     }
@@ -296,9 +325,10 @@ public function JsonBuilder () {
      * Helper function to create dbObject with Array return type
      * Added for consistency as thats default output type
      *
-     * @return dbObject
+     * @return object
      */
-    public function ArrayBuilder () {
+    public function ArrayBuilder()
+    {
         $this->returnType = 'Array';
         return $this;
     }
@@ -306,9 +336,10 @@ public function ArrayBuilder () {
     /**
      * Helper function to create dbObject with Object return type.
      *
-     * @return dbObject
+     * @return object
      */
-    public function ObjectBuilder () {
+    public function ObjectBuilder()
+    {
         $this->returnType = 'Object';
         return $this;
     }
@@ -317,6 +348,7 @@ public function ObjectBuilder () {
      * Method to set a prefix
      *
      * @param string $prefix     Contains a tableprefix
+     * @return object
      */
     public function setPrefix($prefix = '')
     {
@@ -332,26 +364,25 @@ public function setPrefix($prefix = '')
      *
      * @return array Contains the returned rows from the query.
      */
-    public function rawQuery ($query, $bindParams = null)
+    public function rawQuery($query, $bindParams = null)
     {
         $params = array(''); // Create the empty 0 index
         $this->_query = $query;
         $stmt = $this->_prepareQuery();
 
-        if (is_array ($bindParams) === true) {
+        if (is_array($bindParams) === true) {
             foreach ($bindParams as $prop => $val) {
                 $params[0] .= $this->_determineType($val);
                 array_push($params, $bindParams[$prop]);
             }
 
             call_user_func_array(array($stmt, 'bind_param'), $this->refValues($params));
-
         }
 
         $stmt->execute();
         $this->count = $stmt->affected_rows;
         $this->_stmtError = $stmt->error;
-        $this->_lastQuery = $this->replacePlaceHolders ($this->_query, $params);
+        $this->_lastQuery = $this->replacePlaceHolders($this->_query, $params);
         $res = $this->_dynamicBindResults($stmt);
         $this->reset();
 
@@ -368,10 +399,12 @@ public function rawQuery ($query, $bindParams = null)
      *
      * @return array Contains the returned row from the query.
      */
-    public function rawQueryOne ($query, $bindParams = null) {
-        $res = $this->rawQuery ($query, $bindParams);
-        if (is_array ($res) && isset ($res[0]))
+    public function rawQueryOne($query, $bindParams = null)
+    {
+        $res = $this->rawQuery($query, $bindParams);
+        if (is_array($res) && isset($res[0])) {
             return $res[0];
+        }
 
         return null;
     }
@@ -386,21 +419,26 @@ public function rawQueryOne ($query, $bindParams = null) {
      *
      * @return mixed Contains the returned rows from the query.
      */
-    public function rawQueryValue ($query, $bindParams = null) {
-        $res = $this->rawQuery ($query, $bindParams);
-        if (!$res)
+    public function rawQueryValue($query, $bindParams = null)
+    {
+        $res = $this->rawQuery($query, $bindParams);
+        if (!$res) {
             return null;
+        }
 
-        $limit = preg_match ('/limit\s+1;?$/i', $query);
-        $key = key ($res[0]);
-        if (isset($res[0][$key]) && $limit == true)
+        $limit = preg_match('/limit\s+1;?$/i', $query);
+        $key = key($res[0]);
+        if (isset($res[0][$key]) && $limit == true) {
             return $res[0][$key];
+        }
 
-        $newRes = Array ();
-        for ($i = 0; $i < $this->count; $i++)
+        $newRes = Array();
+        for ($i = 0; $i < $this->count; $i++) {
             $newRes[] = $res[$i][$key];
+        }
         return $newRes;
     }
+
     /**
      *
      * @param string $query   Contains a user-provided select query.
@@ -426,29 +464,34 @@ public function query($query, $numRows = null)
      * @uses $MySqliDb->setQueryOption('name');
      *
      * @param string/array $options The optons name of the query.
-     *
+     * @throws Exception
      * @return MysqliDb
      */
-    public function setQueryOption ($options) {
-        $allowedOptions = Array ('ALL','DISTINCT','DISTINCTROW','HIGH_PRIORITY','STRAIGHT_JOIN','SQL_SMALL_RESULT',
-                          'SQL_BIG_RESULT','SQL_BUFFER_RESULT','SQL_CACHE','SQL_NO_CACHE', 'SQL_CALC_FOUND_ROWS',
-                          'LOW_PRIORITY','IGNORE','QUICK', 'MYSQLI_NESTJOIN', 'FOR UPDATE', 'LOCK IN SHARE MODE');
-        if (!is_array ($options))
-            $options = Array ($options);
+    public function setQueryOption($options)
+    {
+        $allowedOptions = Array('ALL', 'DISTINCT', 'DISTINCTROW', 'HIGH_PRIORITY', 'STRAIGHT_JOIN', 'SQL_SMALL_RESULT',
+            'SQL_BIG_RESULT', 'SQL_BUFFER_RESULT', 'SQL_CACHE', 'SQL_NO_CACHE', 'SQL_CALC_FOUND_ROWS',
+            'LOW_PRIORITY', 'IGNORE', 'QUICK', 'MYSQLI_NESTJOIN', 'FOR UPDATE', 'LOCK IN SHARE MODE');
+
+        if (!is_array($options)) {
+            $options = Array($options);
+        }
 
         foreach ($options as $option) {
-            $option = strtoupper ($option);
-            if (!in_array ($option, $allowedOptions))
-                die ('Wrong query option: '.$option);
+            $option = strtoupper($option);
+            if (!in_array($option, $allowedOptions)) {
+                throw new Exception('Wrong query option: ' . $option);
+            }
 
-            if ($option == 'MYSQLI_NESTJOIN')
+            if ($option == 'MYSQLI_NESTJOIN') {
                 $this->_nestJoin = true;
-            else if ($option == 'FOR UPDATE')
+            } elseif ($option == 'FOR UPDATE') {
                 $this->_forUpdate = true;
-            else if ($option == 'LOCK IN SHARE MODE')
+            } elseif ($option == 'LOCK IN SHARE MODE') {
                 $this->_lockInShareMode = true;
-            else
+            } else {
                 $this->_queryOptions[] = $option;
+            }
         }
 
         return $this;
@@ -459,8 +502,9 @@ public function setQueryOption ($options) {
      *
      * @return MysqliDb
      */
-    public function withTotalCount () {
-        $this->setQueryOption ('SQL_CALC_FOUND_ROWS');
+    public function withTotalCount()
+    {
+        $this->setQueryOption('SQL_CALC_FOUND_ROWS');
         return $this;
     }
 
@@ -475,21 +519,25 @@ public function withTotalCount () {
      */
     public function get($tableName, $numRows = null, $columns = '*')
     {
-        if (empty ($columns))
+        if (empty($columns)) {
             $columns = '*';
+        }
 
         $column = is_array($columns) ? implode(', ', $columns) : $columns;
-        if (strpos ($tableName, '.') === false)
+
+        if (strpos($tableName, '.') === false) {
             $this->_tableName = self::$prefix . $tableName;
-        else
+        } else {
             $this->_tableName = $tableName;
+        }
 
         $this->_query = 'SELECT ' . implode(' ', $this->_queryOptions) . ' ' .
-                        $column . " FROM " . $this->_tableName;
+            $column . " FROM " . $this->_tableName;
         $stmt = $this->_buildQuery($numRows);
 
-        if ($this->isSubQuery)
+        if ($this->isSubQuery) {
             return $this;
+        }
 
         $stmt->execute();
         $this->_stmtError = $stmt->error;
@@ -508,14 +556,15 @@ public function get($tableName, $numRows = null, $columns = '*')
      */
     public function getOne($tableName, $columns = '*')
     {
-        $res = $this->get ($tableName, 1, $columns);
+        $res = $this->get($tableName, 1, $columns);
 
-        if ($res instanceof MysqliDb)
+        if ($res instanceof MysqliDb) {
             return $res;
-        else if (is_array ($res) && isset ($res[0]))
+        } elseif (is_array($res) && isset($res[0])) {
             return $res[0];
-        else if ($res)
+        } elseif ($res) {
             return $res;
+        }
 
         return null;
     }
@@ -528,22 +577,25 @@ public function getOne($tableName, $columns = '*')
      *
      * @return mixed Contains the value of a returned column / array of values
      */
-    public function getValue ($tableName, $column, $limit = 1)
+    public function getValue($tableName, $column, $limit = 1)
     {
-        $res = $this->ArrayBuilder()->get ($tableName, $limit, "{$column} AS retval");
+        $res = $this->ArrayBuilder()->get($tableName, $limit, "{$column} AS retval");
 
-        if (!$res)
+        if (!$res) {
             return null;
+        }
 
         if ($limit == 1) {
-            if (isset ($res[0]["retval"]))
+            if (isset($res[0]["retval"])) {
                 return $res[0]["retval"];
+            }
             return null;
         }
 
-        $newRes = Array ();
-        for ($i = 0; $i < $this->count; $i++)
+        $newRes = Array();
+        for ($i = 0; $i < $this->count; $i++) {
             $newRes[] = $res[$i]['retval'];
+        }
         return $newRes;
     }
 
@@ -555,8 +607,9 @@ public function getValue ($tableName, $column, $limit = 1)
      *
      * @return boolean Boolean indicating whether the insert query was completed succesfully.
      */
-    public function insert ($tableName, $insertData) {
-        return $this->_buildInsert ($tableName, $insertData, 'INSERT');
+    public function insert($tableName, $insertData)
+    {
+        return $this->_buildInsert($tableName, $insertData, 'INSERT');
     }
 
     /**
@@ -567,8 +620,9 @@ public function insert ($tableName, $insertData) {
      *
      * @return boolean Boolean indicating whether the insert query was completed succesfully.
      */
-    public function replace ($tableName, $insertData) {
-        return $this->_buildInsert ($tableName, $insertData, 'REPLACE');
+    public function replace($tableName, $insertData)
+    {
+        return $this->_buildInsert($tableName, $insertData, 'REPLACE');
     }
 
     /**
@@ -595,12 +649,13 @@ public function has($tableName)
      */
     public function update($tableName, $tableData)
     {
-        if ($this->isSubQuery)
+        if ($this->isSubQuery) {
             return;
+        }
 
         $this->_query = "UPDATE " . self::$prefix . $tableName;
 
-        $stmt = $this->_buildQuery (null, $tableData);
+        $stmt = $this->_buildQuery(null, $tableData);
         $status = $stmt->execute();
         $this->reset();
         $this->_stmtError = $stmt->error;
@@ -620,14 +675,17 @@ public function update($tableName, $tableData)
      */
     public function delete($tableName, $numRows = null)
     {
-        if ($this->isSubQuery)
+        if ($this->isSubQuery) {
             return;
+        }
 
         $table = self::$prefix . $tableName;
-        if (count ($this->_join))
-            $this->_query = "DELETE " . preg_replace ('/.* (.*)/', '$1', $table) . " FROM " . $table;
-        else
+
+        if (count($this->_join)) {
+            $this->_query = "DELETE " . preg_replace('/.* (.*)/', '$1', $table) . " FROM " . $table;
+        } else {
             $this->_query = "DELETE FROM " . $table;
+        }
 
         $stmt = $this->_buildQuery($numRows);
         $stmt->execute();
@@ -650,13 +708,16 @@ public function delete($tableName, $numRows = null)
     public function where($whereProp, $whereValue = 'DBNULL', $operator = '=', $cond = 'AND')
     {
         // forkaround for an old operation api
-        if (is_array ($whereValue) && ($key = key ($whereValue)) != "0") {
+        if (is_array($whereValue) && ($key = key($whereValue)) != "0") {
             $operator = $key;
             $whereValue = $whereValue[$key];
         }
-        if (count ($this->_where) == 0)
+
+        if (count($this->_where) == 0) {
             $cond = '';
-        $this->_where[] = Array ($cond, $whereProp, $operator, $whereValue);
+        }
+
+        $this->_where[] = Array($cond, $whereProp, $operator, $whereValue);
         return $this;
     }
 
@@ -686,9 +747,8 @@ public function onDuplicate($_updateColumns, $_lastInsertId = null)
      */
     public function orWhere($whereProp, $whereValue = 'DBNULL', $operator = '=')
     {
-        return $this->where ($whereProp, $whereValue, $operator, 'OR');
+        return $this->where($whereProp, $whereValue, $operator, 'OR');
     }
-
     /*
      * This method allows you to specify multiple (method chaining optional) AND HAVING statements for SQL queries.
      *
@@ -699,12 +759,14 @@ public function orWhere($whereProp, $whereValue = 'DBNULL', $operator = '=')
      *
      * @return MysqliDb
      */
+
     public function having($havingProp, $havingValue = null, $operator = null)
     {
-        if ($operator)
-            $havingValue = Array ($operator => $havingValue);
+        if ($operator) {
+            $havingValue = Array($operator => $havingValue);
+        }
 
-        $this->_having[] = Array ("AND", $havingValue, $havingProp);
+        $this->_having[] = Array("AND", $havingValue, $havingProp);
         return $this;
     }
 
@@ -720,10 +782,11 @@ public function having($havingProp, $havingValue = null, $operator = null)
      */
     public function orHaving($havingProp, $havingValue = null, $operator = null)
     {
-        if ($operator)
-            $havingValue = Array ($operator => $havingValue);
+        if ($operator) {
+            $havingValue = Array($operator => $havingValue);
+        }
 
-        $this->_having[] = Array ("OR", $havingValue, $havingProp);
+        $this->_having[] = Array("OR", $havingValue, $havingProp);
         return $this;
     }
 
@@ -735,24 +798,27 @@ public function orHaving($havingProp, $havingValue = null, $operator = null)
      * @param string $joinTable The name of the table.
      * @param string $joinCondition the condition.
      * @param string $joinType 'LEFT', 'INNER' etc.
-     *
+     * @throws Exception
      * @return MysqliDb
      */
-     public function join($joinTable, $joinCondition, $joinType = '')
-     {
+    public function join($joinTable, $joinCondition, $joinType = '')
+    {
         $allowedTypes = array('LEFT', 'RIGHT', 'OUTER', 'INNER', 'LEFT OUTER', 'RIGHT OUTER');
-        $joinType = strtoupper (trim ($joinType));
+        $joinType = strtoupper(trim($joinType));
 
-        if ($joinType && !in_array ($joinType, $allowedTypes))
-            die ('Wrong JOIN type: '.$joinType);
+        if ($joinType && !in_array($joinType, $allowedTypes)) {
+            throw new Exception('Wrong JOIN type: ' . $joinType);
+        }
 
-        if (!is_object ($joinTable))
+        if (!is_object($joinTable)) {
             $joinTable = self::$prefix . $joinTable;
+        }
 
-        $this->_join[] = Array ($joinType,  $joinTable, $joinCondition);
+        $this->_join[] = Array($joinType, $joinTable, $joinCondition);
 
         return $this;
     }
+
     /**
      * This method allows you to specify multiple (method chaining optional) ORDER BY statements for SQL queries.
      *
@@ -760,27 +826,29 @@ public function join($joinTable, $joinCondition, $joinType = '')
      *
      * @param string $orderByField The name of the database field.
      * @param string $orderByDirection Order direction.
-     *
+     * @throws Exception
      * @return MysqliDb
      */
     public function orderBy($orderByField, $orderbyDirection = "DESC", $customFields = null)
     {
-        $allowedDirection = Array ("ASC", "DESC");
-        $orderbyDirection = strtoupper (trim ($orderbyDirection));
-        $orderByField = preg_replace ("/[^-a-z0-9\.\(\),_`\*\'\"]+/i",'', $orderByField);
+        $allowedDirection = Array("ASC", "DESC");
+        $orderbyDirection = strtoupper(trim($orderbyDirection));
+        $orderByField = preg_replace("/[^-a-z0-9\.\(\),_`\*\'\"]+/i", '', $orderByField);
 
         // Add table prefix to orderByField if needed.
         //FIXME: We are adding prefix only if table is enclosed into `` to distinguish aliases
         // from table names
-        $orderByField = preg_replace('/(\`)([`a-zA-Z0-9_]*\.)/', '\1' . self::$prefix.  '\2', $orderByField);
+        $orderByField = preg_replace('/(\`)([`a-zA-Z0-9_]*\.)/', '\1' . self::$prefix . '\2', $orderByField);
 
 
-        if (empty($orderbyDirection) || !in_array ($orderbyDirection, $allowedDirection))
-            die ('Wrong order direction: '.$orderbyDirection);
+        if (empty($orderbyDirection) || !in_array($orderbyDirection, $allowedDirection)) {
+            throw new Exception('Wrong order direction: ' . $orderbyDirection);
+        }
 
-        if (is_array ($customFields)) {
-            foreach ($customFields as $key => $value)
-                $customFields[$key] = preg_replace ("/[^-a-z0-9\.\(\),_`]+/i",'', $value);
+        if (is_array($customFields)) {
+            foreach ($customFields as $key => $value) {
+                $customFields[$key] = preg_replace("/[^-a-z0-9\.\(\),_`]+/i", '', $value);
+            }
 
             $orderByField = 'FIELD (' . $orderByField . ', "' . implode('","', $customFields) . '")';
         }
@@ -800,7 +868,7 @@ public function orderBy($orderByField, $orderbyDirection = "DESC", $customFields
      */
     public function groupBy($groupByField)
     {
-        $groupByField = preg_replace ("/[^-a-z0-9\.\(\),_\*]+/i",'', $groupByField);
+        $groupByField = preg_replace("/[^-a-z0-9\.\(\),_\*]+/i", '', $groupByField);
 
         $this->_groupBy[] = $groupByField;
         return $this;
@@ -836,7 +904,8 @@ public function escape($str)
      *
      * @return bool True if connection is up
      */
-    public function ping() {
+    public function ping()
+    {
         return $this->mysqli()->ping();
     }
 
@@ -879,9 +948,10 @@ protected function _determineType($item)
      *
      * @param string Variable value
      */
-    protected function _bindParam($value) {
-        $this->_bindParams[0] .= $this->_determineType ($value);
-        array_push ($this->_bindParams, $value);
+    protected function _bindParam($value)
+    {
+        $this->_bindParams[0] .= $this->_determineType($value);
+        array_push($this->_bindParams, $value);
     }
 
     /**
@@ -889,9 +959,10 @@ protected function _bindParam($value) {
      *
      * @param Array Variable with values
      */
-    protected function _bindParams ($values) {
+    protected function _bindParams($values)
+    {
         foreach ($values as $value)
-            $this->_bindParam ($value);
+            $this->_bindParam($value);
     }
 
     /**
@@ -901,14 +972,15 @@ protected function _bindParams ($values) {
      *
      * @param Array Variable with values
      */
-    protected function _buildPair ($operator, $value) {
+    protected function _buildPair($operator, $value)
+    {
         if (!is_object($value)) {
-            $this->_bindParam ($value);
-            return ' ' . $operator. ' ? ';
+            $this->_bindParam($value);
+            return ' ' . $operator . ' ? ';
         }
 
-        $subQuery = $value->getSubQuery ();
-        $this->_bindParams ($subQuery['params']);
+        $subQuery = $value->getSubQuery();
+        $this->_bindParams($subQuery['params']);
 
         return " " . $operator . " (" . $subQuery['query'] . ") " . $subQuery['alias'];
     }
@@ -921,23 +993,26 @@ protected function _buildPair ($operator, $value) {
      *
      * @return boolean Boolean indicating whether the insert query was completed succesfully.
      */
-    private function _buildInsert ($tableName, $insertData, $operation)
+    private function _buildInsert($tableName, $insertData, $operation)
     {
-        if ($this->isSubQuery)
+        if ($this->isSubQuery) {
             return;
+        }
 
-        $this->_query = $operation . " " . implode (' ', $this->_queryOptions) ." INTO " .self::$prefix . $tableName;
-        $stmt = $this->_buildQuery (null, $insertData);
+        $this->_query = $operation . " " . implode(' ', $this->_queryOptions) . " INTO " . self::$prefix . $tableName;
+        $stmt = $this->_buildQuery(null, $insertData);
         $stmt->execute();
         $this->_stmtError = $stmt->error;
         $this->reset();
         $this->count = $stmt->affected_rows;
 
-        if ($stmt->affected_rows < 1)
+        if ($stmt->affected_rows < 1) {
             return false;
+        }
 
-        if ($stmt->insert_id > 0)
+        if ($stmt->insert_id > 0) {
             return $stmt->insert_id;
+        }
 
         return true;
     }
@@ -956,29 +1031,33 @@ private function _buildInsert ($tableName, $insertData, $operation)
     protected function _buildQuery($numRows = null, $tableData = null)
     {
         $this->_buildJoin();
-        $this->_buildInsertQuery ($tableData);
+        $this->_buildInsertQuery($tableData);
         $this->_buildCondition('WHERE', $this->_where);
         $this->_buildGroupBy();
         $this->_buildCondition('HAVING', $this->_having);
         $this->_buildOrderBy();
-        $this->_buildLimit ($numRows);
+        $this->_buildLimit($numRows);
         $this->_buildOnDuplicate($tableData);
-        if ($this->_forUpdate)
+        if ($this->_forUpdate) {
             $this->_query .= ' FOR UPDATE';
-        if ($this->_lockInShareMode)
+        }
+        if ($this->_lockInShareMode) {
             $this->_query .= ' LOCK IN SHARE MODE';
+        }
 
-        $this->_lastQuery = $this->replacePlaceHolders ($this->_query, $this->_bindParams);
+        $this->_lastQuery = $this->replacePlaceHolders($this->_query, $this->_bindParams);
 
-        if ($this->isSubQuery)
+        if ($this->isSubQuery) {
             return;
+        }
 
         // Prepare query
         $stmt = $this->_prepareQuery();
 
         // Bind parameters to statement if any
-        if (count ($this->_bindParams) > 1)
+        if (count($this->_bindParams) > 1) {
             call_user_func_array(array($stmt, 'bind_param'), $this->refValues($this->_bindParams));
+        }
 
         return $stmt;
     }
@@ -995,7 +1074,9 @@ protected function _dynamicBindResults(mysqli_stmt $stmt)
     {
         $parameters = array();
         $results = array();
-        // See http://php.net/manual/en/mysqli-result.fetch-fields.php
+        /**
+         * @see http://php.net/manual/en/mysqli-result.fetch-fields.php
+         */
         $mysqlLongType = 252;
         $shouldStoreResult = false;
 
@@ -1003,16 +1084,17 @@ protected function _dynamicBindResults(mysqli_stmt $stmt)
 
         // if $meta is false yet sqlstate is true, there's no sql error but the query is
         // most likely an update/insert/delete which doesn't produce any results
-        if(!$meta && $stmt->sqlstate)
+        if (!$meta && $stmt->sqlstate)
             return array();
 
         $row = array();
         while ($field = $meta->fetch_field()) {
-            if ($field->type == $mysqlLongType)
+            if ($field->type == $mysqlLongType) {
                 $shouldStoreResult = true;
+            }
 
             if ($this->_nestJoin && $field->table != $this->_tableName) {
-                $field->table = substr ($field->table, strlen (self::$prefix));
+                $field->table = substr($field->table, strlen(self::$prefix));
                 $row[$field->table][$field->name] = null;
                 $parameters[] = & $row[$field->table][$field->name];
             } else {
@@ -1024,117 +1106,138 @@ protected function _dynamicBindResults(mysqli_stmt $stmt)
         // avoid out of memory bug in php 5.2 and 5.3. Mysqli allocates lot of memory for long*
         // and blob* types. So to avoid out of memory issues store_result is used
         // https://github.com/joshcam/PHP-MySQLi-Database-Class/pull/119
-        if ($shouldStoreResult)
-             $stmt->store_result();
+        if ($shouldStoreResult) {
+            $stmt->store_result();
+        }
 
         call_user_func_array(array($stmt, 'bind_result'), $parameters);
 
         $this->totalCount = 0;
         $this->count = 0;
+
         while ($stmt->fetch()) {
             if ($this->returnType == 'Object') {
-                $x = new stdClass ();
+                $result = new stdClass ();
                 foreach ($row as $key => $val) {
-                    if (is_array ($val)) {
-                        $x->$key = new stdClass ();
-                        foreach ($val as $k => $v)
-                            $x->$key->$k = $v;
+                    if (is_array($val)) {
+                        $result->$key = new stdClass ();
+                        foreach ($val as $k => $v) {
+                            $result->$key->$k = $v;
+                        }
                     } else
-                        $x->$key = $val;
+                        $result->$key = $val;
                 }
             } else {
-                $x = array();
+                $result = array();
                 foreach ($row as $key => $val) {
                     if (is_array($val)) {
-                        foreach ($val as $k => $v)
-                            $x[$key][$k] = $v;
+                        foreach ($val as $k => $v) {
+                            $result[$key][$k] = $v;
+                        }
                     } else
-                        $x[$key] = $val;
+                        $result[$key] = $val;
                 }
             }
             $this->count++;
             if ($this->_mapKey)
-                $results[$row[$this->_mapKey]] = count ($row) > 2 ? $x : end ($x);
+                $results[$row[$this->_mapKey]] = count($row) > 2 ? $result : end($result);
             else
-                array_push ($results, $x);
+                array_push($results, $result);
         }
-        if ($shouldStoreResult)
+
+        if ($shouldStoreResult) {
             $stmt->free_result();
+        }
+
         $stmt->close();
+
         // stored procedures sometimes can return more then 1 resultset
-        if ($this->mysqli()->more_results())
+        if ($this->mysqli()->more_results()) {
             $this->mysqli()->next_result();
+        }
 
-        if (in_array ('SQL_CALC_FOUND_ROWS', $this->_queryOptions)) {
-            $stmt = $this->mysqli()->query ('SELECT FOUND_ROWS()');
+        if (in_array('SQL_CALC_FOUND_ROWS', $this->_queryOptions)) {
+            $stmt = $this->mysqli()->query('SELECT FOUND_ROWS()');
             $totalCount = $stmt->fetch_row();
             $this->totalCount = $totalCount[0];
         }
-        if ($this->returnType == 'Json')
-            return json_encode ($results);
+
+        if ($this->returnType == 'Json') {
+            return json_encode($results);
+        }
 
         return $results;
     }
 
-
     /**
      * Abstraction method that will build an JOIN part of the query
      */
-    protected function _buildJoin () {
-        if (empty ($this->_join))
+    protected function _buildJoin()
+    {
+        if (empty($this->_join)) {
             return;
+        }
 
         foreach ($this->_join as $data) {
-            list ($joinType,  $joinTable, $joinCondition) = $data;
+            list ($joinType, $joinTable, $joinCondition) = $data;
 
-            if (is_object ($joinTable))
-                $joinStr = $this->_buildPair ("", $joinTable);
-            else
+            if (is_object($joinTable)) {
+                $joinStr = $this->_buildPair("", $joinTable);
+            } else {
                 $joinStr = $joinTable;
+            }
 
-            $this->_query .= " " . $joinType. " JOIN " . $joinStr ." on " . $joinCondition;
+            $this->_query .= " " . $joinType . " JOIN " . $joinStr . " on " . $joinCondition;
         }
     }
 
-    public function _buildDataPairs ($tableData, $tableColumns, $isInsert) {
+    /**
+     * 
+     * @throws Exception
+     */
+    public function _buildDataPairs($tableData, $tableColumns, $isInsert)
+    {
         foreach ($tableColumns as $column) {
             $value = $tableData[$column];
-            if (!$isInsert)
+
+            if (!$isInsert) {
                 $this->_query .= "`" . $column . "` = ";
+            }
 
             // Subquery value
             if ($value instanceof MysqliDb) {
-                $this->_query .= $this->_buildPair ("", $value) . ", ";
+                $this->_query .= $this->_buildPair("", $value) . ", ";
                 continue;
             }
 
             // Simple value
-            if (!is_array ($value)) {
+            if (!is_array($value)) {
                 $this->_bindParam($value);
                 $this->_query .= '?, ';
                 continue;
             }
 
             // Function value
-            $key = key ($value);
+            $key = key($value);
             $val = $value[$key];
             switch ($key) {
-            case '[I]':
-                $this->_query .= $column . $val . ", ";
-                break;
-            case '[F]':
-                $this->_query .= $val[0] . ", ";
-                if (!empty ($val[1]))
-                    $this->_bindParams ($val[1]);
-                break;
-            case '[N]':
-                if ($val == null)
-                    $this->_query .= "!" . $column . ", ";
-                else
-                    $this->_query .= "!" . $val . ", ";
-                break;
-            default:
-                die ("Wrong operation");
+                case '[I]':
+                    $this->_query .= $column . $val . ", ";
+                    break;
+                case '[F]':
+                    $this->_query .= $val[0] . ", ";
+                    if (!empty($val[1])) {
+                        $this->_bindParams($val[1]);
+                    }
+                    break;
+                case '[N]':
+                    if ($val == null)
+                        $this->_query .= "!" . $column . ", ";
+                    else
+                        $this->_query .= "!" . $val . ", ";
+                    break;
+                default:
+                    throw new Exception("Wrong operation");
             }
         }
         $this->_query = rtrim($this->_query, ', ');
@@ -1149,85 +1252,93 @@ protected function _buildOnDuplicate($tableData)
     {
         if (is_array($this->_updateColumns) && !empty($this->_updateColumns)) {
             $this->_query .= " on duplicate key update ";
-            if ($this->_lastInsertId)
-                $this->_query .= $this->_lastInsertId . "=LAST_INSERT_ID (".$this->_lastInsertId."), ";
+            if ($this->_lastInsertId) {
+                $this->_query .= $this->_lastInsertId . "=LAST_INSERT_ID (" . $this->_lastInsertId . "), ";
+            }
 
             foreach ($this->_updateColumns as $key => $val) {
                 // skip all params without a value
-                if (is_numeric ($key)) {
+                if (is_numeric($key)) {
                     $this->_updateColumns[$val] = '';
-                    unset ($this->_updateColumns[$key]);
+                    unset($this->_updateColumns[$key]);
                 } else
                     $tableData[$key] = $val;
             }
-            $this->_buildDataPairs ($tableData, array_keys ($this->_updateColumns), false);
+            $this->_buildDataPairs($tableData, array_keys($this->_updateColumns), false);
         }
     }
 
     /**
      * Abstraction method that will build an INSERT or UPDATE part of the query
      */
-    protected function _buildInsertQuery ($tableData) {
-        if (!is_array ($tableData))
+    protected function _buildInsertQuery($tableData)
+    {
+        if (!is_array($tableData)) {
             return;
+        }
 
-        $isInsert = preg_match ('/^[INSERT|REPLACE]/', $this->_query);
-        $dataColumns = array_keys ($tableData);
-        if ($isInsert)
-            $this->_query .= ' (`' . implode ($dataColumns, '`, `') . '`)  VALUES (';
-        else
+        $isInsert = preg_match('/^[INSERT|REPLACE]/', $this->_query);
+        $dataColumns = array_keys($tableData);
+        if ($isInsert) {
+            $this->_query .= ' (`' . implode($dataColumns, '`, `') . '`)  VALUES (';
+        } else {
             $this->_query .= " SET ";
+        }
 
-        $this->_buildDataPairs ($tableData, $dataColumns, $isInsert);
+        $this->_buildDataPairs($tableData, $dataColumns, $isInsert);
 
-        if ($isInsert)
+        if ($isInsert) {
             $this->_query .= ')';
+        }
     }
 
     /**
      * Abstraction method that will build the part of the WHERE conditions
      */
-    protected function _buildCondition ($operator, &$conditions) {
-        if (empty ($conditions))
+    protected function _buildCondition($operator, &$conditions)
+    {
+        if (empty($conditions)) {
             return;
+        }
 
         //Prepare the where portion of the query
         $this->_query .= ' ' . $operator;
 
         foreach ($conditions as $cond) {
             list ($concat, $varName, $operator, $val) = $cond;
-            $this->_query .= " " . $concat ." " . $varName;
+            $this->_query .= " " . $concat . " " . $varName;
 
-            switch (strtolower ($operator)) {
+            switch (strtolower($operator)) {
                 case 'not in':
                 case 'in':
-                    $comparison = ' ' . $operator. ' (';
-                    if (is_object ($val)) {
-                        $comparison .= $this->_buildPair ("", $val);
+                    $comparison = ' ' . $operator . ' (';
+                    if (is_object($val)) {
+                        $comparison .= $this->_buildPair("", $val);
                     } else {
                         foreach ($val as $v) {
                             $comparison .= ' ?,';
-                            $this->_bindParam ($v);
+                            $this->_bindParam($v);
                         }
                     }
-                    $this->_query .= rtrim($comparison, ',').' ) ';
+                    $this->_query .= rtrim($comparison, ',') . ' ) ';
                     break;
                 case 'not between':
                 case 'between':
                     $this->_query .= " $operator ? AND ? ";
-                    $this->_bindParams ($val);
+                    $this->_bindParams($val);
                     break;
                 case 'not exists':
                 case 'exists':
-                    $this->_query.= $operator . $this->_buildPair ("", $val);
+                    $this->_query.= $operator . $this->_buildPair("", $val);
                     break;
                 default:
-                    if (is_array ($val))
-                        $this->_bindParams ($val);
-                    else if ($val === null)
+                    if (is_array($val)) {
+                        $this->_bindParams($val);
+                    } elseif ($val === null) {
                         $this->_query .= $operator . " NULL";
-                    else if ($val != 'DBNULL' || $val == '0')
-                        $this->_query .= $this->_buildPair ($operator, $val);
+                    } elseif ($val != 'DBNULL' || $val == '0') {
+                        $this->_query .= $this->_buildPair($operator, $val);
+                    }
             }
         }
     }
@@ -1236,13 +1347,17 @@ protected function _buildCondition ($operator, &$conditions) {
      * Abstraction method that will build the GROUP BY part of the WHERE statement
      *
      */
-    protected function _buildGroupBy () {
-        if (empty ($this->_groupBy))
+    protected function _buildGroupBy()
+    {
+        if (empty($this->_groupBy)) {
             return;
+        }
 
         $this->_query .= " GROUP BY ";
-        foreach ($this->_groupBy as $key => $value)
+
+        foreach ($this->_groupBy as $key => $value) {
             $this->_query .= $value . ", ";
+        }
 
         $this->_query = rtrim($this->_query, ', ') . " ";
     }
@@ -1251,19 +1366,22 @@ protected function _buildGroupBy () {
      * Abstraction method that will build the LIMIT part of the WHERE statement
      *
      */
-    protected function _buildOrderBy () {
-        if (empty ($this->_orderBy))
+    protected function _buildOrderBy()
+    {
+        if (empty($this->_orderBy)) {
             return;
+        }
 
         $this->_query .= " ORDER BY ";
         foreach ($this->_orderBy as $prop => $value) {
-            if (strtolower (str_replace (" ", "", $prop)) == 'rand()')
+            if (strtolower(str_replace(" ", "", $prop)) == 'rand()') {
                 $this->_query .= "rand(), ";
-            else
+            } else {
                 $this->_query .= $prop . " " . $value . ", ";
+            }
         }
 
-        $this->_query = rtrim ($this->_query, ', ') . " ";
+        $this->_query = rtrim($this->_query, ', ') . " ";
     }
 
     /**
@@ -1272,14 +1390,17 @@ protected function _buildOrderBy () {
      * @param integer|array $numRows Array to define SQL limit in format Array ($count, $offset)
      *                               or only $count
      */
-    protected function _buildLimit ($numRows) {
-        if (!isset ($numRows))
+    protected function _buildLimit($numRows)
+    {
+        if (!isset($numRows)) {
             return;
+        }
 
-        if (is_array ($numRows))
-            $this->_query .= ' LIMIT ' . (int)$numRows[0] . ', ' . (int)$numRows[1];
-        else
-            $this->_query .= ' LIMIT ' . (int)$numRows;
+        if (is_array($numRows)) {
+            $this->_query .= ' LIMIT ' . (int) $numRows[0] . ', ' . (int) $numRows[1];
+        } else {
+            $this->_query .= ' LIMIT ' . (int) $numRows;
+        }
     }
 
     /**
@@ -1290,10 +1411,13 @@ protected function _buildLimit ($numRows) {
      */
     protected function _prepareQuery()
     {
-        if (!$stmt = $this->mysqli()->prepare($this->_query))
-            throw new Exception ("Problem preparing query ($this->_query) " . $this->mysqli()->error);
-        if ($this->traceEnabled)
-            $this->traceStartQ = microtime (true);
+        if (!$stmt = $this->mysqli()->prepare($this->_query)) {
+            throw new Exception("Problem preparing query ($this->_query) " . $this->mysqli()->error);
+        }
+
+        if ($this->traceEnabled) {
+            $this->traceStartQ = microtime(true);
+        }
 
         return $stmt;
     }
@@ -1303,8 +1427,10 @@ protected function _prepareQuery()
      */
     public function __destruct()
     {
-        if ($this->isSubQuery)
+        if ($this->isSubQuery) {
             return;
+        }
+
         if ($this->_mysqli) {
             $this->_mysqli->close();
             $this->_mysqli = null;
@@ -1321,10 +1447,11 @@ protected function refValues(Array &$arr)
         //Reference in the function arguments are required for HHVM to work
         //https://github.com/facebook/hhvm/issues/5155
         //Referenced data array is required by mysqli since PHP 5.3+
-        if (strnatcmp (phpversion(), '5.3') >= 0) {
+        if (strnatcmp(phpversion(), '5.3') >= 0) {
             $refs = array();
-            foreach ($arr as $key => $value)
+            foreach ($arr as $key => $value) {
                 $refs[$key] = & $arr[$key];
+            }
             return $refs;
         }
         return $arr;
@@ -1337,21 +1464,25 @@ protected function refValues(Array &$arr)
      *
      * @return string
      */
-    protected function replacePlaceHolders ($str, $vals) {
+    protected function replacePlaceHolders($str, $vals)
+    {
         $i = 1;
         $newStr = "";
 
-        if (empty ($vals))
+        if (empty($vals)) {
             return $str;
+        }
 
-        while ($pos = strpos ($str, "?")) {
+        while ($pos = strpos($str, "?")) {
             $val = $vals[$i++];
-            if (is_object ($val))
+            if (is_object($val)) {
                 $val = '[object]';
-            if ($val === NULL)
+            }
+            if ($val === null) {
                 $val = 'NULL';
-            $newStr .= substr ($str, 0, $pos) . "'". $val . "'";
-            $str = substr ($str, $pos + 1);
+            }
+            $newStr .= substr($str, 0, $pos) . "'" . $val . "'";
+            $str = substr($str, $pos + 1);
         }
         $newStr .= $str;
         return $newStr;
@@ -1362,7 +1493,8 @@ protected function replacePlaceHolders ($str, $vals) {
      *
      * @return string
      */
-    public function getLastQuery () {
+    public function getLastQuery()
+    {
         return $this->_lastQuery;
     }
 
@@ -1371,10 +1503,12 @@ public function getLastQuery () {
      *
      * @return string
      */
-    public function getLastError () {
-        if (!$this->_mysqli)
+    public function getLastError()
+    {
+        if (!$this->_mysqli) {
             return "mysqli is null";
-        return trim ($this->_stmtError . " " . $this->mysqli()->error);
+        }
+        return trim($this->_stmtError . " " . $this->mysqli()->error);
     }
 
     /**
@@ -1383,20 +1517,22 @@ public function getLastError () {
      *
      * @return array
      */
-    public function getSubQuery () {
-        if (!$this->isSubQuery)
+    public function getSubQuery()
+    {
+        if (!$this->isSubQuery) {
             return null;
+        }
 
-        array_shift ($this->_bindParams);
-        $val = Array ('query' => $this->_query,
-                      'params' => $this->_bindParams,
-                      'alias' => $this->host
-                );
+        array_shift($this->_bindParams);
+        $val = Array('query' => $this->_query,
+            'params' => $this->_bindParams,
+            'alias' => $this->host
+        );
         $this->reset();
         return $val;
     }
-
     /* Helper functions */
+
     /**
      * Method returns generated interval function as a string
      *
@@ -1407,24 +1543,36 @@ public function getSubQuery () {
      * @param string Initial date
      *
      * @return string
-    */
-    public function interval ($diff, $func = "NOW()") {
-        $types = Array ("s" => "second", "m" => "minute", "h" => "hour", "d" => "day", "M" => "month", "Y" => "year");
+     */
+    public function interval($diff, $func = "NOW()")
+    {
+        $types = Array("s" => "second", "m" => "minute", "h" => "hour", "d" => "day", "M" => "month", "Y" => "year");
         $incr = '+';
         $items = '';
         $type = 'd';
 
-        if ($diff && preg_match('/([+-]?) ?([0-9]+) ?([a-zA-Z]?)/',$diff, $matches)) {
-            if (!empty ($matches[1])) $incr = $matches[1];
-            if (!empty ($matches[2])) $items = $matches[2];
-            if (!empty ($matches[3])) $type = $matches[3];
-            if (!in_array($type, array_keys($types)))
+        if ($diff && preg_match('/([+-]?) ?([0-9]+) ?([a-zA-Z]?)/', $diff, $matches)) {
+            if (!empty($matches[1])) {
+                $incr = $matches[1];
+            }
+
+            if (!empty($matches[2])) {
+                $items = $matches[2];
+            }
+
+            if (!empty($matches[3])) {
+                $type = $matches[3];
+            }
+
+            if (!in_array($type, array_keys($types))) {
                 throw new Exception("invalid interval type in '{$diff}'");
-            $func .= " ".$incr ." interval ". $items ." ".$types[$type] . " ";
+            }
+
+            $func .= " " . $incr . " interval " . $items . " " . $types[$type] . " ";
         }
         return $func;
-
     }
+
     /**
      * Method returns generated interval function as an insert/update function
      *
@@ -1435,45 +1583,53 @@ public function interval ($diff, $func = "NOW()") {
      * @param string Initial date
      *
      * @return array
-    */
-    public function now ($diff = null, $func = "NOW()") {
-        return Array ("[F]" => Array($this->interval($diff, $func)));
+     */
+    public function now($diff = null, $func = "NOW()")
+    {
+        return array("[F]" => Array($this->interval($diff, $func)));
     }
 
     /**
      * Method generates incremental function call
      * @param int increment by int or float. 1 by default
+     * @throws Exception
      */
-    public function inc($num = 1) {
-        if(!is_numeric($num))
-            throw new Exception ('Argument supplied to inc must be a number');
-        return Array ("[I]" => "+" . $num);
+    public function inc($num = 1)
+    {
+        if (!is_numeric($num)) {
+            throw new Exception('Argument supplied to inc must be a number');
+        }
+        return array("[I]" => "+" . $num);
     }
 
     /**
      * Method generates decrimental function call
      * @param int increment by int or float. 1 by default
      */
-    public function dec ($num = 1) {
-        if(!is_numeric($num))
-            throw new Exception ('Argument supplied to dec must be a number');
-        return Array ("[I]" => "-" . $num);
+    public function dec($num = 1)
+    {
+        if (!is_numeric($num)) {
+            throw new Exception('Argument supplied to dec must be a number');
+        }
+        return array("[I]" => "-" . $num);
     }
 
     /**
      * Method generates change boolean function call
      * @param string column name. null by default
      */
-    public function not ($col = null) {
-        return Array ("[N]" => (string)$col);
+    public function not($col = null)
+    {
+        return array("[N]" => (string) $col);
     }
 
     /**
      * Method generates user defined function call
      * @param string user function body
      */
-    public function func ($expr, $bindParams = null) {
-        return Array ("[F]" => Array($expr, $bindParams));
+    public function func($expr, $bindParams = null)
+    {
+        return array("[F]" => Array($expr, $bindParams));
     }
 
     /**
@@ -1481,7 +1637,7 @@ public function func ($expr, $bindParams = null) {
      */
     public static function subQuery($subQueryAlias = "")
     {
-        return new MysqliDb (Array('host' => $subQueryAlias, 'isSubQuery' => true));
+        return new self(array('host' => $subQueryAlias, 'isSubQuery' => true));
     }
 
     /**
@@ -1489,9 +1645,9 @@ public static function subQuery($subQueryAlias = "")
      *
      * @param object new mysqlidb object
      */
-    public function copy ()
+    public function copy()
     {
-        $copy = unserialize (serialize ($this));
+        $copy = unserialize(serialize($this));
         $copy->_mysqli = $this->_mysqli;
         return $copy;
     }
@@ -1502,10 +1658,11 @@ public function copy ()
      * @uses mysqli->autocommit(false)
      * @uses register_shutdown_function(array($this, "_transaction_shutdown_check"))
      */
-    public function startTransaction () {
-        $this->mysqli()->autocommit (false);
+    public function startTransaction()
+    {
+        $this->mysqli()->autocommit(false);
         $this->_transaction_in_progress = true;
-        register_shutdown_function (array ($this, "_transaction_status_check"));
+        register_shutdown_function(array($this, "_transaction_status_check"));
     }
 
     /**
@@ -1514,10 +1671,11 @@ public function startTransaction () {
      * @uses mysqli->commit();
      * @uses mysqli->autocommit(true);
      */
-    public function commit () {
-        $this->mysqli()->commit ();
+    public function commit()
+    {
+        $this->mysqli()->commit();
         $this->_transaction_in_progress = false;
-        $this->mysqli()->autocommit (true);
+        $this->mysqli()->autocommit(true);
     }
 
     /**
@@ -1526,10 +1684,11 @@ public function commit () {
      * @uses mysqli->rollback();
      * @uses mysqli->autocommit(true);
      */
-    public function rollback () {
-      $this->mysqli()->rollback ();
-      $this->_transaction_in_progress = false;
-      $this->mysqli()->autocommit (true);
+    public function rollback()
+    {
+        $this->mysqli()->rollback();
+        $this->_transaction_in_progress = false;
+        $this->mysqli()->autocommit(true);
     }
 
     /**
@@ -1538,10 +1697,12 @@ public function rollback () {
      *
      * @uses mysqli->rollback();
      */
-    public function _transaction_status_check () {
-        if (!$this->_transaction_in_progress)
+    public function _transaction_status_check()
+    {
+        if (!$this->_transaction_in_progress) {
             return;
-        $this->rollback ();
+        }
+        $this->rollback();
     }
 
     /**
@@ -1549,25 +1710,29 @@ public function _transaction_status_check () {
      *
      * @param bool $enabled Enable execution time tracking
      * @param string $stripPrefix Prefix to strip from the path in exec log
-     **/
-    public function setTrace ($enabled, $stripPrefix = null) {
+     * */
+    public function setTrace($enabled, $stripPrefix = null)
+    {
         $this->traceEnabled = $enabled;
         $this->traceStripPrefix = $stripPrefix;
         return $this;
     }
+
     /**
      * Get where and what function was called for query stored in MysqliDB->trace
      *
      * @return string with information
      */
-    private function _traceGetCaller () {
-        $dd = debug_backtrace ();
-        $caller = next ($dd);
-        while (isset ($caller) &&  $caller["file"] == __FILE__ )
+    private function _traceGetCaller()
+    {
+        $dd = debug_backtrace();
+        $caller = next($dd);
+        while (isset($caller) && $caller["file"] == __FILE__) {
             $caller = next($dd);
+        }
 
         return __CLASS__ . "->" . $caller["function"] . "() >>  file \"" .
-                str_replace ($this->traceStripPrefix, '', $caller["file"] ) . "\" line #" . $caller["line"] . " " ;
+            str_replace($this->traceStripPrefix, '', $caller["file"]) . "\" line #" . $caller["line"] . " ";
     }
 
     /**
@@ -1577,16 +1742,20 @@ private function _traceGetCaller () {
      *
      * @returns boolean True if table exists
      */
-    public function tableExists ($tables) {
-        $tables = !is_array ($tables) ? Array ($tables) : $tables;
-        $count = count ($tables);
-        if ($count == 0)
+    public function tableExists($tables)
+    {
+        $tables = !is_array($tables) ? Array($tables) : $tables;
+        $count = count($tables);
+        if ($count == 0) {
             return false;
+        }
 
-        array_walk ($tables, function (&$value, $key) { $value = self::$prefix . $value; });
-        $this->where ('table_schema', $this->db);
-        $this->where ('table_name', $tables, 'IN');
-        $this->get ('information_schema.tables', $count);
+        array_walk($tables, function (&$value, $key) {
+            $value = self::$prefix . $value;
+        });
+        $this->where('table_schema', $this->db);
+        $this->where('table_name', $tables, 'IN');
+        $this->get('information_schema.tables', $count);
         return $this->count == $count;
     }
 
@@ -1597,8 +1766,11 @@ public function tableExists ($tables) {
      *
      * @return Array Returns an array($k => $v) if get(.."param1, param2"), array ($k => array ($v, $v)) otherwise
      */
-    public function map ($idField) {
+    public function map($idField)
+    {
         $this->_mapKey = $idField;
         return $this;
     }
-} // END class
+}
+
+// END class
\ No newline at end of file