Excel formula needed

I have a spreadsheet with 2 tabs

one tab has a list of thousands of company names and in the next column is a code that relates to that company in my database

the second tab contains data that i want to import into my database, it has company names that match SOME of the companies in the first tab

in order to import the data i need to replace the company names with the code from the first tab



to explain again in a different way to be clear... i need the company names in tab 2 to go and find their code from tab 1 and replace their name with their code


it should just be a formula but i have no idea what it is

please help, it will take the right person 10 mins but that is not me !