codeigniter active record bug?

[eluser]Unknown[/eluser]
Hi all

I want to know if this is a bug , or just my mistake

when i want to select two column of datetime type

this works

Code:

$this->db->select("promotion_id as pkey, code, name, DATE_FORMAT(start_date, '%d %b, %Y'), DATE_FORMAT(end_date,'%d %b %Y'), total_qty, rent_day", false);

but this doesn't works

Code:

$this->db->select("promotion_id as pkey, code, name, DATE_FORMAT(start_date, '%d %b, %Y'), DATE_FORMAT(end_date,'%d %b, %Y'), total_qty, rent_day", false);

is this a bug or what?