This query works well for me in mysql but I want to pass it to the CodeIgniter form, models

I already found the answer both search and search ...

class Cobradores_model extends CI_Model {

    public function getCobradores(){
        $query = $this->db->query("SELECT registro.*,CONCAT(usuarios.apellidos,', ',usuarios.nombres) as appnom FROM (SELECT *, bingo+chancho+pollada as total FROM (SELECT idusuario, sum(pagado) as bingo, sum('') as chancho, sum('') as pollada, 1 as tarjeta FROM tbingo b WHERE pagado=1 GROUP BY idusuario
        union all
        SELECT idusuario,  sum('') as bingo, sum(pagado) as chancho, sum('') as pollada, 2 as tarjeta FROM tchancho c WHERE pagado=1 GROUP BY idusuario
        union all
        SELECT idusuario,  sum('') as bingo, sum('') as chancho, sum(pagado) as pollada, 3 as tarjeta FROM tpollada  p WHERE pagado=1  GROUP BY idusuario) as tabla  
        GROUP BY idusuario) as registro join usuarios  ON registro.idusuario=usuarios.id");
        return $query->result();
    }
}