Codeigniter doesn`t save sessions on database - mysql

Question

I`m trying to save my session on database without success. I already set CI config, autoload and nothing works.
On my controller
$session_data = array(
'session_id' => session_id(),
'ip_address' => $this->input->ip_address(),
'user_agent' => $this->input->user_agent(),
'last_activity' => substr($_SERVER['HTTP_USER_AGENT'], 0, 120),
'user_data' => 'logged'
);
$this->session->set_userdata('ci_sessions', $session_data);
Autoload
$autoload['libraries'] = array('database','session');
$autoload['drivers'] = array('session');
Config
$config['encryption_key'] = 'wqf35MV437ytPyGweGHH24775zK8u7uD';
$config['sess_driver'] = 'files';
$config['sess_cookie_name'] = 'ci_sessions';
$config['sess_encrypt_cookie'] = FALSE;
$config['sess_expiration'] = 8640;
$config['sess_use_database'] = TRUE;
$config['sess_table_name'] = 'ci_sessions';
$config['sess_expire_on_close'] = TRUE;
$config['sess_save_path'] = NULL;
$config['sess_match_ip'] = TRUE;
$config['sess_match_useragent'] = TRUE;
$config['sess_time_to_update'] = 300;
$config['sess_regenerate_destroy'] = FALSE;
And default ci_session table on MYSQL
CREATE TABLE IF NOT EXISTS 'ci_sessions' (
session_id varchar(40) DEFAULT '0' NOT NULL,
ip_address varchar(45) DEFAULT '0' NOT NULL,
user_agent varchar(120) NOT NULL,
last_activity int(10) unsigned DEFAULT 0 NOT NULL,
user_data text NOT NULL,
PRIMARY KEY (session_id),
KEY 'last_activity_idx' ('last_activity')
);

Answer 1

You have mixed your CI2 session config up with CI3 session config.
Session Database User Guide CI3
If your using CodeIgniter 3 If you would like to save session to database
change
$config['sess_driver'] = 'files';
$config['sess_save_path'] = NULL;
To
$config['sess_driver'] = 'database';
// This will be your table name for session
$config['sess_save_path'] = 'ci_sessions';
$config['sess_expiration'] = 7200;
$config['sess_match_ip'] = TRUE;
$config['sess_time_to_update'] = 300;
$config['sess_regenerate_destroy'] = FALSE;
And
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,
KEY `ci_sessions_timestamp` (`timestamp`)
);
Then I would autoload session
$autoload['libraries'] = array('session');