SQL Server: Only last entry in GROUP BY

Question

I have the following table in MSSQL2005

id | business_key | result
1 | 1 | 0
2 | 1 | 1
3 | 2 | 1
4 | 3 | 1
5 | 4 | 1
6 | 4 | 0

And now i wa

Answer 1

An alternative solution, which may give you better performance (test both ways and check the execution plans):

SELECT
     T1.id,
     T1.business_key,
     T1.result
FROM
     dbo.My_Table T1
LEFT OUTER JOIN dbo.My_Table T2 ON
     T2.business_key = T1.business_key AND
     T2.id > T1.id
WHERE
     T2.id IS NULL

This query assumes that the ID is a unique value (at least for any given business_key) and that it is set to NOT NULL.