codice:update tabella as tab1, (select max(id) as id from tabella where id_offerta = '001') as tab2 set tab1.computo = 'quello che vuoi' where tab1.id = tab2.id
codice:update tabella as tab1, (select max(id) as id from tabella where id_offerta = '001') as tab2 set tab1.computo = 'quello che vuoi' where tab1.id = tab2.id