Show the apartment numbers of apartments with bookings that have status code both "Provisional" and "Confirmed"
SELECT T2.apt_number FROM Apartment_Bookings AS T1 JOIN Apartments AS T2 ON T1.apt_id  =  T2.apt_id WHERE T1.booking_status_code  =  "Confirmed" INTERSECT SELECT T2.apt_number FROM Apartment_Bookings AS T1 JOIN Apartments AS T2 ON T1.apt_id  =  T2.apt_id WHERE T1.booking_status_code  =  "Provisional"
apartment numbers refers to apt_number; apartments with bookings that have status code both 'Provisional' and 'Confirmed' requires filtering bookings with both status codes and finding their associated apartment numbers; use of INTERSECT to find apartments that meet both conditions; joining 'Apartment_Bookings' table with 'Apartments' table to link booking status to apartment numbers.