CREATE TABLE body_builder (body_builder_id NUMBER, people_id NUMBER, snatch NUMBER, clean_jerk NUMBER, total NUMBER)
CREATE TABLE people (people_id NUMBER, name CLOB, height NUMBER, weight NUMBER, birth_date CLOB, birth_place CLOB)

How many persons are not body builders?
SELECT COUNT(*) FROM people WHERE NOT people_id IN (SELECT people_id FROM body_builder)
SELECT COUNT(*) FROM "people" WHERE NOT "people_id" IN (SELECT "people_id" FROM "body_builder")