Thread: Linking 2 spreadsheets without using vlookup or range lookup

I am working on two giant Excel spreadsheets that contain customer databases. One spreadsheet has customer IDs and customer names in foreign languages. The other one has customer IDs, and alternative customer names in English.

Basically what I am trying to do is to link one spreadsheet to the other. What is the best way to do it without using the "vlookup" or range lookup function?

Now that is normally not a problem if the customer list is stored on one single worksheet. The one I've got here has 6 different tabs, each one has around 65000+ rows of records.

Hope this makes sense, help would be greatly appreciated