Subtracting 30 Years from Current Date in Oracle SQL

Question

I need to write a query in which I select all people who have a date of birth over 30 years ago. Unfortunately, as I am using Oracle I cannot use the DATEADD() function.

I have currently got this, but obviously this isn't dynamic and won't change as the years pass:

SELECT Name, DOB
FROM Employee
WHERE DOB <= DATE '1985-01-01';

Answer 1

Use Add_MONTHS to add (- 12 * 30).

SELECT Name, DOB
FROM Employee
WHERE DOB <= ADD_MONTHS(SYSDATE, -(12 * 30));