php - combining mysql AND OR queries in Codeigniter

Question

I want to combine AND OR mysql queries in CI. I have already seen this thread: http://codeigniter.com/forums/viewthread/92818/. But they don't provide the exact solution there.

How do I create the following query using strictly the CI framework? (I can create the query easily without the brackets but then it is not the same query.)

SELECT * FROM `Persons` WHERE
LastName='Svendson' AND Age="12" AND
(FirstName='Tove' OR FirstName='Ola' OR Gender="M" OR Country="India") 

P.S.: This is just a sample query even if it makes no sense & Do not suggest writing the entire OR part of the query inside a single where().

EDIT: Basically I want the implementation of the following simple query:

SELECT * FROM `table` WHERE field1='value1' AND (field2='value2' OR field3='value3') 

Answer 1

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();