In Orcle7 the top-N and bottom-N queries are much more complicated (particularry the top-N, where you have to sort records in descending order) and much less efficient.

If we stick with the "top 5 paid employees" example from SCOTT.EMP, here are three different queries that will return correct results. The first one is the most "straightforward", but also by far the most inefficient for large tables. The last one is the fastest one, particulary if there is an index on the sorting column. Note also that if there are equal values at the end of the result set (e.g. if there are more then one employee with the same salary at the fifth position) the first query will return none of them, while other two will return only one of them.

1. With corelated subquery
SELECT * FROM scott.emp e1 WHERE 5 >=
(SELECT COUNT(sal)
FROM scott.emp e2
WHERE e2.sal >= e1.sal)
ORDER BY e1.sal DESC;

2. With inline view
SELECT emp.* FROM emp,
(SELECT rowid x, -1*sal FROM emp GROUP BY -1*sal, rowid) e2
WHERE emp.rowid = e2.x AND rownum <= 5
ORDER BY emp.sal DESC;

3. With "dummy" outer join
SELECT emp.* FROM emp, dual
WHERE -1*emp.sal = DECODE(dual.dummy(+), 'X', NULL, NULL)
AND rownum <= 10
ORDER BY emp.sal DESC;

HTH,