Active Record : how to update the data

[eluser]adwin[/eluser]
How to implement this query into CI activerecord

Code:

sql = "update myincome set expense=expense + 1000 where id = 1 "

I just don't know how to write

Code:

expense = expense + 1000

thnx

[eluser]Armchair Samurai[/eluser]
Probably:

Code:

$this->db->set('expense', 'expense + 1000', FALSE);
$this->db->where('id', 1);
$this->db->update('myincome');

[eluser]Michael Wales[/eluser]

Code:

$this->db->set('expense', 'expense + 1000', FALSE);
$this->db->where('id', 1);
$this->db->update('myincome');

[eluser]adwin[/eluser]
thanks ... that would be helpful