SQL & PL/SQL

I have a Table Emp with the following Structure

SQL> desc emp
Name Null? Type
----------------------------------------- -------- -------------
---------------
EMPNO NUMBER(2)
ENAME VARCHAR2(50)
HIREDATE DATE
DEPTNO NUMBER(2)

If I write a following query on this table

SQL> SELECT deptno, hiredate, record_id
2 FROM (SELECT deptno, ename, hiredate, ROW_NUMBER()
3 OVER (ORDER BY hiredate) AS record_id
4 FROM emp)
5 WHERE record_id >= 2
6 AND record_id <=5;

The Result I get is


DEPTNO HIREDATE RECORD_ID
---------- --------- ----------
10 22-NOV-01 2
10 22-NOV-01 3
10 22-NOV-01 4
10 22-NOV-01 5

But if I put this query in a cursor in a PL/SQL block. The
pl/sql does not compiles and gives me the following address

SQL> DECLARE
2 CURSOR c_my IS
3 SELECT deptno, hiredate, record_id
4 FROM (SELECT deptno, ename, hiredate, ROW_NUMBER()
5 OVER (ORDER BY hiredate) AS record_id
6 FROM emp)
7 WHERE record_id >= 2
8 AND record_id <=5;
9 BEGIN
10 FOR c_rec IN c_my LOOP
11 dbms_output.put_line(c_rec.ename);
12 END LOOP;
13 END;
14 /
OVER (ORDER BY hiredate) AS record_id
*
ERROR at line 5:
ORA-06550: line 5, column 13:
PLS-00103: Encountered the symbol "(" when expecting one of the
following:
, from


Question: Can you please tell me how I can use the ROW_NUMBER()
function in PL/SQL. I need to use this for selecting the correct
range of records for Pagination on a website.


Thanks in advance
Prashant