How to make sql selection by age having only date of birth?

Question

MySQL

Good afternoon, please tell me how to make a choice of clients, for example, who are 50 years old.
A solution like
YEAR(DOB) = (YEAR(NOW()) - 50) Doesn't work because I need to be sure that the person is 50 full years old.

Answer 1

50 = YEAR(DATE_SUB(NOW(), INTERVAL TO_DAYS(DOB) DAY))

Answer 2

You can try this:
select datediff(yy, DOB, NOW())

Answer 3

Age:

DATEDIFF( Year, BirthDay, ISNULL( DeathDay, GETDATE())) 
+ ( SIGN ( DATEDIFF ( DAY, BirthDay, DATEADD ( YEAR, YEAR( BirthDay ) 
- YEAR( ISNULL( DeathDay, GETDATE())), ISNULL( DeathDay, GETDATE())))) - 1 ) / 2