diff --git a/system/drivers/DB_mysqli.php b/system/drivers/DB_mysqli.php
index 4b96857..a5237c8 100644
--- a/system/drivers/DB_mysqli.php
+++ b/system/drivers/DB_mysqli.php
@@ -85,7 +85,7 @@
 	 * @param	string	an SQL query
 	 * @return	resource
 	 */	
-	function execute($sql)
+	function _execute($sql)
 	{
 		$sql = $this->_prep_query($sql);	
 		$result = @mysqli_query($this->conn_id, $sql);
@@ -117,7 +117,86 @@
 		
 		return $sql;
     }
-	
+
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Begin Transaction
+	 * 
+	 * @access	public
+	 * @return	bool		 
+	 */	
+	function trans_begin()
+	{
+		if ( ! $this->trans_enabled)
+		{
+			return TRUE;
+		}
+		
+		// When transactions are nested we only begin/commit/rollback the outermost ones
+		if ($this->_trans_depth > 0)
+		{
+			return TRUE;
+		}
+
+		$this->simple_query('SET AUTOCOMMIT=0');
+		$this->simple_query('START TRANSACTION'); // can also be BEGIN or BEGIN WORK
+		return TRUE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Commit Transaction
+	 * 
+	 * @access	public
+	 * @return	bool		 
+	 */	
+	function trans_commit()
+	{
+		if ( ! $this->trans_enabled)
+		{
+			return TRUE;
+		}
+
+		// When transactions are nested we only begin/commit/rollback the outermost ones
+		if ($this->_trans_depth > 0)
+		{
+			return TRUE;
+		}
+
+		$this->simple_query('COMMIT');
+		$this->simple_query('SET AUTOCOMMIT=1');
+		return TRUE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Rollback Transaction
+	 * 
+	 * @access	public
+	 * @return	bool		 
+	 */	
+	function trans_rollback()
+	{
+		if ( ! $this->trans_enabled)
+		{
+			return TRUE;
+		}
+
+		// When transactions are nested we only begin/commit/rollback the outermost ones
+		if ($this->_trans_depth > 0)
+		{
+			return TRUE;
+		}
+
+		$this->simple_query('ROLLBACK');
+		$this->simple_query('SET AUTOCOMMIT=1');
+		return TRUE;
+	}
+
 	// --------------------------------------------------------------------
 
 	/**