To run the code, cut and paste it onto your favourite editor and save the file. When you run it through SQL*PLUS, it asks you to specify a value for the 'topN' value. So for example if you want to display the top 4 salaries, specify a value 4 for topN (see sample output below).

When used with the emp table, as in the example, you get the following output.

SQL>	SELECT	empno,	ename, sal, deptno
	FROM	emp a
	WHERE	&topN >	(SELECT count(1)
			FROM emp) b
			WHERE b.sal > a.sal
Enter	value for	topN: 4

EMPNO	ENAME	SAL	DEPTNO
---------	---------	----------	---------
7566	JONES	2975	20
7788	SCOTT	3000	20
7839	KING	5000	10
7902	FORD	3000	20

SQL>