CREATE TABLE table_name_74 (date VARCHAR2, event VARCHAR2, heat_semifinal_final VARCHAR2)

What date was the men's 100m breaststroke in heat 6?
SELECT date FROM table_name_74 WHERE event = "men's 100m breaststroke" AND heat_semifinal_final = "heat 6"
SELECT "date" FROM "table_name_74" WHERE "event" = "men's 100m breaststroke" AND "heat 6" = "heat_semifinal_final"