How to populate data in worksheet though there is no record for the item_id,location_id,sales_date c

Hi,

     We have a series with server expression which computes the data and shows in the worksheet, its working fine for those combinations which exists in sales_data table and it returns null for those combinations which are not in sales_Data table item_id,location_id,sales_Date. Please advice how to populate the data in the worksheet even though corresponding combination does not exists in sales data table and same item_id location_id combination exists in mdp_matrix table.

Regards,

VVM