How to get nᵗʰ highest value using plain SQL

Question

What is the simplest way to get the n^th highest value from a result set using plain SQL?

The result set would be huge, thus need to consider performance too.

Answer 1

This is the T-SQL (SQL-Server 2005 and greater) approach using ROW_NUMBER:

WITH CTE AS
(
   SELECT 
      Col1, Col2, ValueCol,
      RN = ROW_NUMBER() OVER (ORDER BY ValueCol DESC) -- change to ASC if you want lowest first
   FROM 
      dbo.TableName
)
SELECT 
   Col1, Col2, ValueCol
FROM 
   CTE
WHERE 
   RN = @nthhighestvalue

If you want all rows with the same value use DENSE RANK instead.

Difference between ROW_NUMBER, RANK and DENSE_RANK