Comparing files in BPCS and SQL server

["Amitava Banerjee" <Amitava.Banerjee@xxxxxxxx>]

Hi
Another dept. in my company has a system running on SQL server. I work in BPCS 
6.0.04 and don't know anything about SQL server. Now, I have to compare some 
files across these two systems (for example, an Invoice file in that other 
system with RCM in BPCS to see whether all the customer no.s in that other file 
are in RCM or not). My first thought was to import that file in AS/400 
(somehow) and then compare. But I am told not to duplicate any file ( that 
means I can not copy [import or export] any file from one system to another). 
Is there any other way to do it?
TIA
Amitava