Question

I’d like to get this to redirect to welcome/stats/3 asuming site_id is 3

function add_keyword()
{
    $data = array(
        'keyword' => $this->input->post('keywords'),
        'depth' => $this->input->post('depth'),
        'site_id' => $this->input->post('site_id')
    );

    $site_id = $this->input->post('site_id');

    $this->site_model->add_keyword($data);
    redirect('welcome/stats/', $site_id); 
}

Answer 1

You have to concatenate $site_id, not pass it as a second parameter:

redirect('welcome/stats/' . $site_id);