The proxy rewrites SQL queries to perform them over encrypted columns stored on server. An encrypted column may be an onion with several layers of encryption. Assume that the server has a employee table with three columns: name, SSN, and salary, and that all three are encrypted using an onion.
To what query does the proxy rewrite the query select SUM(salary) from employee where name="Alice"? (If CryptDB removes any onion layers, please explain which onion layers are removed.)