Database Forge Class does not create the table

Hi all,
I try to create table into my db but i can't. System give no error messages. Any suggestion?


CONTROLLER

PHP Code:

<?php
defined('BASEPATH') OR exit('No direct script access allowed');

class Tables extends CI_Controller {
        public function __construct()
        {
                parent::__construct();
                $this->load->model('table_model');
        }
        public function index()
        {
                $fields = array(
                    'blog_id' => array(
                        'type' => 'INT',
                        'constraint' => 5,
                        'unsigned' => TRUE,
                        'auto_increment' => TRUE
                    ),
                    'blog_title' => array(
                            'type' => 'VARCHAR',
                            'constraint' => '100',
                            'unique' => TRUE,
                    ),
                    'blog_author' => array(
                            'type' =>'VARCHAR',
                            'constraint' => '100',
                            'default' => 'King of Town',
                    ),
                    'blog_description' => array(
                            'type' => 'TEXT',
                            'null' => TRUE,
                    ),
                );
                $this->table_model->create_table($fields);   
        }
} 


MODEL

PHP Code:

<?php
defined('BASEPATH') OR exit('No direct script access allowed');
class Table_model extends CI_Model {

    public function __construct()
    {
        $this->load->database();
        $this->load->dbforge();
    }
    public function create_table($data)
    {
        //print_r($data);
        $this->dbforge->add_field($data);
        $this->dbforge->create_table('mytable',TRUE);
    }
}