how to validate user's login?

[eluser]Tony W[/eluser]
I used the form helper to generate a form for login including the username and password fields.

In my function, I used the following to catch the submitted info:

Code:

$username = $this->input->post('username', TRUE);
    $password = $this->input->post('password', TRUE);

I wonder how to validate the username and password (to compare with the usernames and passwords in mysql database).

Can I use this db query?

Code:

$this->db->where('username', $username);