Question

How to select Top 40% from a table without using the Top clause (or Top percent, the assignment is a little ambiguous) ? This question is for T-SQL, SQL Server 2008. I am not allowed to use Top for my assignment.

Thanks.

This is what I’ve tried but seems complicated. Isn’t there an easier way ?

select top (convert (int, (select round (0.4*COUNT(*), 0) from MyTable))) * from MyTable

Answer 1

A problem with the NTILE(10) answers given so far is that if the table has 15 rows they will return 8 rows (53%) rather than the correct number to make up 40% (6).

If the number of rows is not evenly divisible by number of buckets the extra rows all go into the first buckets rather than being evenly distributed.

This alternative (borrows SQL Menace’s table) avoids that issue.

WITH CTE
     AS (SELECT *,
                ROW_NUMBER() OVER ( ORDER BY Score) AS RN,
                COUNT(*) OVER()                     AS Cnt
         FROM   #temp)
SELECT StudentID,
       Score
FROM   CTE
WHERE  RN <= CEILING(0.4 * Cnt )