problem with function in order_items export

Hello,

I must add a column to “order_items” csv file.



In the function I must use the reference “'key' => array ('item_id', 'order_id')”



This is the call:



'Markup' => array (

'db_field' => 'product_id',

'process_get' => array ('fn_markup_get', '# key')

),





This is the function



fn_markup_get function ($ keys, $ Poid) {

setlocale (LC_MONETARY, 'en_US');

$ total = '0, 00 ';

$ data = db_get_field ("SELECT (a.price - (b.milan_price - b.logatura_price)) as markup cscart_order_detailsFROMa, where b cscart_products a.order_id =? = i and a.item_id? s and b.product_id a.product_id = ", $ key ['order_id'], $ key ['item_id']);



if (empty ($ data))

money_format $ total = ('% .2 n', $ data);



return $ total;

}



The problem is that I can not display any data in csv file.

I use the # key object in the wrong way? I mistake the way to call the function?



Please, hep me



Thk!

any ideas?

Please help!