Ud over PHP-løsninger, som andre tilbyder, kan du oprette endDate
lige inde i MySQL og spar dig selv for besværet:
SELECT startDate, DATE_ADD(startDate, INTERVAL 60 DAY) AS endDate FROM table;
-- Or by months (not exactly the same thing)
SELECT startDate, DATE_ADD(startDate, INTERVAL 2 MONTH) AS endDate FROM table;
Relevant dokumentation her.. .