I just want to delete row from db table by passing an id.

Here is my Model:

public function did_delete_row($user_id)
{ 
    $query = $this->db->get_where('users', array('user_id' => $user_id));
    if ($query->num_rows() == 1) {
        if ($this->db->delete('users', array('user_id', 'email', 'name', 'city'))) {
            return true;
        } else {
            return false;
        }
    } else {
        return false;
    }
}

Here is my view:

Delete

Here is my controller:

public function delete_row($user_id)
{
    $this->load->model("model_admin");
    $this->model_admin->did_delete_row($user_id);
}

My model returns true, but the targeted row isn't deleted. Whatis going wrong?