Hi,

If I understand correctly in this specific scenario you will have a list of Code Combinations values coming from a third party which you need to verify against the list of code combinations values which have been setup in system.

This can be achieved in various ways:

1. Pass the GL Code Combination Value as a parameter to existing Web Service Call (I hope there is one)which will return success or failure depending on whether the value exists in application base tables. But, this I hope will not meet your requirement.
2. Load the values into a Custom Lookup / UDT and then using SQLs try to fetch all combinations of records which are not-matching. Collate all such entries , prepare a report and then send the report (inline / attachment) using email to concerned stakeholders. This might suit you with the only challenge being each time you get a new file ( from 3rd party) you would need to update the Lookup /UDT.
3. This one by far would be the best approach (not sure whether feasible though). Create a custom BI Report using this Excel (I presume the Cost Center Values from 3rd party is in a spreadsheet) as one Data Set and SQL query from application base tables (which would fetch all code combination values another Data Set as and then find all values from Data Set1 which does not exist in Data Set 2.

Kind Regards
Ashish