How many competitors over the age of 30 participated in the 1992 Winter Olympics?
competitors over the age of 30 refer to person_id where age > 30; the 1992 Winter Olympics refers to games_name = '1992 Winter';
SELECT COUNT(T2.person_id) FROM games AS T1 INNER JOIN games_competitor AS T2 ON T1.id = T2.games_id WHERE T1.games_name = '1992 Winter' AND T2.age > 30