select - codeigniter, get the maximum value in mysql table column -

i'm using codeigniter 2.
i've mysql table column storing time taken each student.
eg. 1.2327, 0.6547, 1.9876

i want max. value column.

this code:

$this->db->select_max('time_taken', 'time'); $result = $this->db->get('students');   echo $result->row()->time; 

when echo result, give me value of 2(correct value should 1.9876).
correct way value need, thanks?

try:

$this->db->select_max('time_taken time'); $result = $this->db->get('students')->row();   echo $result->time; 

edit: make sure database table field (i.e time_taken) decimal, not integer.