Это мой запрос за 30 дней до проверки:
select id from users where
((TO_DAYS(concat(DATE_FORMAT(NOW(),'%Y'), '-', DATE_FORMAT(date_of_birth, '%m-%d')))-TO_DAYS(NOW()))>=-30
AND (TO_DAYS(concat(DATE_FORMAT(NOW(),'%Y'), '-', DATE_FORMAT(date_of_birth, '%m-%d')))-TO_DAYS(NOW()))<=0)
OR (TO_DAYS(concat(DATE_FORMAT(NOW(),'%Y'), '-', DATE_FORMAT(date_of_birth, '%m-%d')))-TO_DAYS(NOW()))>=(365-31)
и 30 дней после:
select id from users where
((TO_DAYS(NOW())-TO_DAYS(concat(DATE_FORMAT(NOW(),'%Y'), '-', DATE_FORMAT(date_of_birth, '%m-%d'))))>=-31
AND (TO_DAYS(NOW())-TO_DAYS(concat(DATE_FORMAT(NOW(),'%Y'), '-', DATE_FORMAT(date_of_birth, '%m-%d'))))<=0)
OR (TO_DAYS(NOW())-TO_DAYS(concat(DATE_FORMAT(NOW(),'%Y'), '-', DATE_FORMAT(date_of_birth, '%m-%d'))))>=(365-30)