How do I write this SQL statement ?

[eluser]Unknown[/eluser]
Hi everyone,

I have this SQL statement :

Select * from `abc_table` abc
where abc.field1 = 1 and
(
abc.field2 = 2 and
(abc.field = 3 or abc.field4 = 4)
);

If don't use $this->db->query() statement, how do I write this statement (by $this->db->where...)

Thanks for helping.