SQL>
SQL> DECLARE
2 PROCEDURE myProc (dt IN VARCHAR2) IS
3 BEGIN
4 DBMS_OUTPUT.PUT_LINE (dt || ' -> ' || ADD_MONTHS (dt, 1));
5 END;
6 BEGIN
7 myProc ('30-JAN-99');
8 myProc ('27-FEB-99');
9 END;
10 /
30-JAN-99 -> 28-FEB-99
27-FEB-99 -> 27-MAR-99
PL/SQL procedure successfully completed.
SQL>