I am building an ajax web application and i am displaying a chain select in jquery that does some selecting behind the scenes and saves me lots of time writing new routes and views.However,i would like to know if there is a way i could reduce my work further by not writing new models.

I have this `controller` 

```
<?php
class Tools extends CI_Controller {

    public function message($to = 'World')
    {
        echo "Hello {$to}!".PHP_EOL;
    }
    public function boom(){
    echo "boom".PHP_EOL;
    }
    public function q(){
    $sql = "SELECT * FROM members WHERE member_id = ? AND member_club_id = ? AND membership_year = ?";

    $count = $this->db->query($sql, array(null, 1, null));
    foreach ($count->result() as $row)
    {
    echo $row->member_name . PHP_EOL; 
    }
    }
}
?>

```

which is an attempt to skip some column and display some other.

This is its sql equivalent

```
SELECT * FROM members WHERE member_id = null AND member_club_id = 1 AND membership_year = null;

```

They both don't display anything.Is there a way i can skip a column of my choosing?.