how to do multiple selects and arithmetic using Active Record

[eluser]Seppo[/eluser]

Code:

$this->db->select('value_SI, description');
$this->db->from('values');
$this->db->where("value_SI < (SELECT 1/(SELECT convert2SI FROM `units` WHERE unit='hands'))");
$this->db->order_by("value_SI", "DESC");
$this->db->limit(4);

That generates, in mysql driver,

SELECT `value_SI`, `description` FROM (`values`) WHERE `value_SI` < (SELECT 1/(SELECT convert2SI FROM `units` WHERE unit='hands')) ORDER BY `value_SI` DESC LIMIT 4

it is not as good as AR could be, because it probably won't work on all db systems, but it's the best you can do...