Here’s a simple query to find the Nth Maximum and Minimum values in a SQL Server table column using the Row_Number() function. We will find the 3rd highest and 3rd lowest values in the column.
DECLARE @tmp TABLE(id integer, amount integer)
INSERT INTO @tmp values(4, 9543)
INSERT INTO @tmp values(6, 34)
INSERT INTO @tmp values(3, 54)
INSERT INTO @tmp values(2, 6632)
INSERT INTO @tmp values(5, 645)
INSERT INTO @tmp values(1, 1115)
INSERT INTO @tmp values(7, 345)
-- FIND Nth Maximum value
SELECT id, amount
FROM
(
SELECT id, amount, Row_Number() OVER(ORDER BY amount DESC) AS highest
FROM @tmp
) as x
WHERE highest = 3
-- FIND Nth Minimum value
SELECT id, amount
FROM
(
SELECT id, amount, Row_Number() OVER(ORDER BY amount ASC) AS lowest
FROM @tmp
) as x
WHERE lowest = 3
OUTPUT
The first output shows the 3rd maximum value in the column whereas the second output shows the 3rd minimum value in the column
3 comments:
Other possible methods
http://beyondrelational.com/blogs/madhivanan/archive/2007/08/27/find-nth-maximum-value.aspx
Works but not as advertised, this returns the 2nd highest and lowest
Actualy it does work as advertised, but the results shown do not match the code. The results show the second highest/lowest entries, code is for the third.
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