It's no problem to have multiple files open at the same time. Just use a different filehandle:

open(FILEa,"/path/to/file");
open(FILE2,"/path/to/another/file");
[download]

I'm not sure about iterating through two files at once though. Perhaps a more experienced monk knows of a way to do that. Without seeing some sample data or the criteria on which you will match records, it's hard to offer much help. However, I would probably use a hash instead of an array. Hashes are much better forthat type of comparison.

Show us some sample data nd what you have tried so far, and I'm sure you will get more help.

By the way, welcome to The Monastery.