Add or Remove years from Date Time in SQL server

Add or Remove years from Date Time in SQL server.md

1. Add 5 years to user date of birth timestamp

update user set date_of_birth=dateadd(year, 5, date_of_birth) where datepart(year, date_of_birth)>1965;

2. Remove 100 years from user date of birth timestamp

update user set date_of_birth=dateadd(year , -100, date_of_birth) where datepart(year, date_of_birth)>2015;