Changes compared to CodeIgniter 2:

• The framework is released under the MIT license
  
• The database drivers have had extensive refactoring
  
• PDO is fully functional with subdrivers
  
• There is a new Session library
  
• There is a new Encryption library
  
• The unit testing has been beefed up, and code coverage improved
  
• PHP 5.4 or newer is recommended, but CI will still work on PHP 5.2.4

http://forum.codeigniter.com/thread-1657-post-7480.html#pid7480

Link https://wiki.archlinux.org/index.php/PhpMyAdmin

Link 1: Not work in my computer.
https://github.com/ntung/Codeigniter-login-logout-register
Link 2: Work well but need to change some things. Link: http://www.kodingmadesimple.com/2014/08/how-to-create-login-form-codeigniter-mysql-twitter-bootstrap.html

CREATE TABLE IF NOT EXISTS `users` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `username` varchar(255) NOT NULL DEFAULT '',
  `email` varchar(255) NOT NULL DEFAULT '',
  `password` varchar(255) NOT NULL DEFAULT '',
  `avatar` varchar(255) DEFAULT 'default.jpg',
  `created_at` datetime NOT NULL,
  `updated_at` datetime DEFAULT NULL,
  `is_admin` tinyint(1) unsigned NOT NULL DEFAULT '0',
  `is_confirmed` tinyint(1) unsigned NOT NULL DEFAULT '0',
  `is_deleted` tinyint(1) unsigned NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`)
);
CREATE TABLE IF NOT EXISTS `ci_sessions` (
        `id` varchar(40) NOT NULL,
        `ip_address` varchar(45) NOT NULL,
        `timestamp` int(10) unsigned DEFAULT 0 NOT NULL,
        `data` blob NOT NULL,
        PRIMARY KEY (id),
        KEY `ci_sessions_timestamp` (`timestamp`)
);

create table ci_session if we modify in config.php

Why? Please see here: http://forum.codeigniter.com/thread-50019-page-2.html

http://stackoverflow.com/questions/3613704/mysql-show-current-connection-info

http://www.dailymail.co.uk/health/article-2110674/How-stop-husband-wife-wrecking-nights-sleep-snoring.html