combining mysql AND OR queries in Codeigniter

In CodeIgniter 3 there are new methods group_start() and group_end() which serve exactly for this purpose.

return $this->db     ->where('LastName', 'Svendson');     ->where('Age', 12);     ->group_start()         ->where('FirstName','Tove')         ->or_where('FirstName','Ola')         ->or_where('Gender','M')         ->or_where('Country','India')     ->group_end()     ->get('Persons')     ->result();

and this will work?

$this->db->where('LastName', 'Svendson');$this->db->where('Age', 12);$this->db->where("(FirstName='Tove' OR FirstName='Ola' OR Gender='M' OR Country='India')", NULL, FALSE);$query = $this->db->get('Persons');return $query->result();

using codeigniter 3.0 frame work,there is new feature available for separate or where and where operation.that is,group by and group end

code like,

$this->db->where('LastName', 'Svendson');$this->db->where('Age', 12);$this->db->group_start();$this->db->or_where('FirstName','Tove');$this->db->or_where('FirstName','Ola');$this->db->or_where('Gender','M');$this->db->or_where('Country','India');$this->db->group_end();$query = $this->db->get('Persons');return $query->result();