CREATE TABLE Addresses (zip_postcode VARCHAR, address_id VARCHAR)
CREATE TABLE Student_Addresses (address_id VARCHAR)

What are the id and zip code of the address with the highest monthly rental?
SELECT T2.address_id, T1.zip_postcode FROM Addresses AS T1 JOIN Student_Addresses AS T2 ON T1.address_id = T2.address_id ORDER BY monthly_rental DESC LIMIT 1
SELECT "T2"."address_id", "T1"."zip_postcode" FROM "Addresses" AS "T1" JOIN "Student_Addresses" AS "T2" ON "T1"."address_id" = "T2"."address_id" ORDER BY "monthly_rental" DESC NULLS LAST LIMIT 1