<code>
PROCEDURE PC_CAST
   ( v_number IN varchar2,
     v_date IN varchar2)
   IS
    v_summe number;
    v_sysdate date;
BEGIN
    v_summe := to_number(v_number) + 2;
    dbms_output.put_line('Summe: ' || v_summe);
    
    select sysdate - v_date into v_sysdate
        from dual;
    dbms_output.put_line('Sysdate: ' || v_sysdate);

EXCEPTION
   WHEN value_error THEN
       dbms_output.put_line('Bitte nur Zahlen eingeben!');
END;
</code>