If you need to find the number of years someone has worked for you then the following type of query should do the trick:
SELECT EMPNO, ENAME,
TRUNC((SYSDATE-HIREDATE)/365) as YEARS_OF_SERVICE
FROM EMP
How to Find Years of Service of Employee
If you need to find the number of years someone has worked for you then the following type of query should do the trick:
SELECT EMPNO, ENAME,
TRUNC((SYSDATE-HIREDATE)/365) as YEARS_OF_SERVICE
FROM EMP