how can i read just one field from a db table

[eluser]alebenson[/eluser]
hi there!.. basic stuff here again
i cant understand this
i just want to read only 1 field of my DB... the content of the Image from some ID

here is what i am doing

Code:

$this->db->select('image');
$this->db->where('id', $id);
$JustTheImage = $this->db->get('post');

but by the whole things i've try to readit the only one that works is just a forech
a foreach for a single thing has no sense