[solved!] A Database Error Occurred

[eluser]WebsiteDuck[/eluser]
You need to put backticks around the first return like so:

Code:

$this->db->select('SUM(gross) as sales, SUM(paid) as payment, SUM(credit) as credit, SUM(debit) as debit, SUM(`return`) as `return`');

Also $data['client_id'] doesn't exist, per your error