codeigniter mysql bitwise operator

I have a value in my database (int) decimal. I have several constants in my codeigniter application linked to a binary 1 - 2 - 4 - 8 - ... .

I wanted to get all users with a specific binary acces level to be shown.

public function query($level = 0)
{
    $data = NULL;
$this->db->select('user_id, user_email, user_name, user_firstname, user_imageammount, user_auth');
$this->db->from('users');
$this->db->where('user_auth' & $level);

$query = $this->db->get();

if ( $query->num_rows() > 0 )
{
    $data = $query->result_array();
}

return $data;

}

When i run the query straight in my phpmyadmin i get the results that i need.

SELECT user_id, user_email, user_name, user_firstname, user_imageammount, user_auth FROM users WHERE user_auth & 1

When i run it in codeigniter i get a error.

Severity: Warning Message: A non-numeric value encountered

Any help or advice would be appriciated.

#php #mysql #codeigniter