select * from t1 where hours_worked_per_week = 40 and weeks_worked_last_year = 52 and dob < '1949-11-21';
id id2 dob address city hours_worked_per_week weeks_worked_last_year
16 16 1949-11-07 address16 city16 40 52
50 50 1923-09-08 address50 city50 40 52
select * from t1 IGNORE INDEX(dob, weeks_worked_last_year, hours_worked_per_week) where hours_worked_per_week = 40 and weeks_worked_last_year = 52 and dob < '1949-11-21';
id id2 dob address city hours_worked_per_week weeks_worked_last_year