SQL update from one Table to another based on a ID match

Question

I have a database with account numbers and card numbers. I match these to a file to update any card numbers to the account number, so

Answer 1

Oracle 11g

merge into Sales_Import
using RetrieveAccountNumber
on (Sales_Import.LeadId = RetrieveAccountNumber.LeadId)
when matched then update set Sales_Import.AccountNumber = RetrieveAccountNumber.AccountNumber;