Codeigniter.md

get Last query executed

echo $this->db->last_query();

storing session in ci

Simple :

First, load this library

$this->load->library('session');
Then, to add some informations in session :

$newdata = array(
                   'username'  => 'johndoe',
                   'email'     => '[email protected]',
                   'logged_in' => TRUE
               );

$this->session->set_userdata($newdata);

fething session in ci

print_r($this->session->userdata); 
or
print_r($this->session->all_userdata());
for single session
$session_id = $this->session->userdata('session_id');

removing session in ci

$this->session->unset_userdata('some_name');